|
94 z28 stock lt1 to 383
Hello all,
I am new to the whole car thing in general. I was a mechanic in the navy and worked on gigantic steam engines and turbines and all sorts of equipment on a nuclear aircraft carrier. My girlfriend is a super car nerd and basically got a 97 z28 as her first car, and now she has 3 and is a UTI graduate and a Mercedes Benz drive graduate (first female to graduate from drive) and knows everything there is to know about cars, except what I want to know... whether she actually doesnt know or is just a butt I dont know. So my question is about my 94 z28 I just got about a month ago. The transmission was allegedly rebuilt 10k miles ago, and the engine is standing at 199966 right this second, trying to snap the pic of the big 200k! And I will hopefully have a good paying job starting next month, and I've been trying to compile my wishlist for this car. I want to buy the monster in a box 4l60e ss kit rated at 600hp and rebuild this transmission, I want to get a Ford 9 inch with maybe a 3.5-3.7 gear ratio, but I would like you guys to correct me if I should get something more appropriate, I want to put either 17 or 18 inch rims, 10 wide on the back and probably 8 on the front, And i want to convert my lt1 to a 383, and I am sure I can find a kit online, but I also want to know what size fuel injectors, what size spark plugs, what size fuel pump I would need with the kit to complete it, and what AFR would be best. (i also know that the heads need to be sent to a machinist along with the block so the cylinders can be bored i believe 0.030 over to 4.030 and all that, so I'm thinking of finding a engine shop nearish to me and paying them one price to rebuild it and do machining work and conversion as that will probably be cheaper than buying a crate engine and buying the kit and sending the heads and block off, I've read several forums so far and this is just my thought I could be wrong) And I am also wanting opinions as to whether a blower would be appropriate. I dont want a turbo, and I'm not opposed to a supercharger because I love the look of a big blower, but they are really expensive and im not looking to race this car really, maybe take it to the track every once in a blue moon, but I want this to be my beautiful weekend car. So I want around 500 hp, not too much and not too little lol. Any and all info/opinions/ideas I greatly appreciate. I have just completely sunk into the car world now, staying up until 3am watching all sorts of videos. https://cimg5.ibsrv.net/gimg/www.cam...eb64d24099.jpg My 94 z28 beasty |
Re: 94 z28 stock lt1 to 383
Lots of questions, we'll try to help answer them. But first I'm going to move your post to a more appropriate forum, where you are more likely to get the help you need. “Drivetrain” is only for the parts that come after the engine - clutch, trans, driveshaft, rear axle.
To clarify one of your points - you indicate you want a “blower”, but would also be open to a “supercharger”, but prefer the blower. They are both the same thing. There are different kinds of superchargers, including centrifugal and positive displacement. Is that somehow related to your idea of the differentiation between a blower an a supercharger? As a general rule, centrifugal supercharger kits are readily available for the LT1, while a positive displacement (like an Eaton) would pretty much be a one-off, custom build. |
Re: 94 z28 stock lt1 to 383
Originally Posted by Injuneer
(Post 7002475)
Lots of questions, we'll try to help answer them. But first I'm going to move your post to a more appropriate forum, where you are more likely to get the help you need. “Drivetrain” is only for the parts that come after the engine - clutch, trans, driveshaft, rear axle.
To clarify one of your points - you indicate you want a “blower”, but would also be open to a “supercharger”, but prefer the blower. They are both the same thing. There are different kinds of superchargers, including centrifugal and positive displacement. Is that somehow related to your idea of the differentiation between a blower an a supercharger? As a general rule, centrifugal supercharger kits are readily available for the LT1, while a positive displacement (like an Eaton) would pretty much be a one-off, custom build. |
Re: 94 z28 stock lt1 to 383
WHAT IS YOUR BUDGET?
I want to buy the monster in a box 4l60e ss kit rated at 600hp and rebuild this transmission, Ok, good idea. The 4L60E is not exactly stout in stock form. I want to get a Ford 9 inch with maybe a 3.5-3.7 gear ratio, but I would like you guys to correct me if I should get something more appropriate, Why? Why not just build out the factory 10-bolt? Unless you're planning on making a drag car or something with loads of power, this is an unnecessary expense. People bag on the 10 bolt a lot, but built properly with good parts - they can take a lot of abuse. For the A4, 3.73 is a nice compromise between performance and hwy mpg. And i want to convert my lt1 to a 383, and I am sure I can find a kit online, but I also want to know what size fuel injectors, what size spark plugs, what size fuel pump I would need with the kit to complete it, and what AFR would be best. (i also know that the heads need to be sent to a machinist along with the block so the cylinders can be bored i believe 0.030 over to 4.030 and all that, so I'm thinking of finding a engine shop nearish to me and paying them one price to rebuild it and do machining work and conversion as that will probably be cheaper than buying a crate engine and buying the kit and sending the heads and block off, I've read several forums so far and this is just my thought I could be wrong) Or you can just purchase the entire engine, assembled from Golen. Karl Ellwein is pretty much the best LT builder out there, but I don't think he's building as many now. The rest of your questions all require proper selection of your cam and heads. Anyone that tries to tell you what injectors, plugs, etc before a cam has been spec'd is a fool. Get the shortblock built, and then go to Lloyd Elliot (http://elliottsportworks.com/) to get the heads and cam sorted out. And I am also wanting opinions as to whether a blower would be appropriate. I dont want a turbo, and I'm not opposed to a supercharger because I love the look of a big blower, but they are really expensive and im not looking to race this car really, maybe take it to the track every once in a blue moon, but I want this to be my beautiful weekend car. So I want around 500 hp, not too much and not too little lol. Crossing over into the forced-induction ballpark is an entirely different thing and your budget just doubled. At least. You can easily get 500 hp (crank) without going FI so you should carefully weigh the pros and cons of this decision. You made no mention of a converter, and you'll definitely need a custom tune - preferably a dyno-tune. |
Re: 94 z28 stock lt1 to 383
HP GOAL:
First, you indicate you are looking for 500 HP. Is that at the engine's flywheel, or at the vehicle's rear wheels? The 4L60E/drivetrain will lose 15-17% of the power by the time it reaches the rear wheels. 500 HP at the flywheel is maybe 415 - 425 HP at the rear wheels. It is possible to make 500 HP at the flywheel without a power adder (S/C. turbo, nitrous) or increasing the displacement to 383 cubic inches. Making 500 HP at the rear wheels (~600 HP at the flywheel) is possible, without the power adder or additional displacement, but that isn't going to be a friendly car for the street. Added displacement (383 ci) makes it easier to make HP, and provides added low end torque, The larger displacement, the milder the cam required (and the less radical a large cam feels), and fewer issues with surging, tuning, etc.. A S/C on a stock displacement 350 ci LT1 engine (but not stock internals) can easily make 500 HP at the rear wheels. Buddy of mine did a Vortech S/C on a 383 displacement and made 1,125 HP at the flywheel. How fast do you want to go..... how many $$$$$ do you want to spend. From personal experience, 425 HP at the rear wheels is a fun car to drive on the street. |
Re: 94 z28 stock lt1 to 383
Wow! So much I don't know! I will go ahead and cross off the FI route as I am not really that interested in doubling the cost (quick search proved that), and also to clarify my mistake, I am looking at 500 hp at the flywheel, not making a race car, just a badass car lol. I would like to spend $10k on this, less is better obviously, but this is my list that I'm going to be knocking out over a period of time when I start my career hopefully next month, so more is also okay.
I like the idea of building on the stock rear diff, I just read that the 9 inch is about the toughest you can get, but I've found that they are pretty pricey, so how would I go about upgrading this? Better aftermarket 3rd member with 3.73 ratio? Better Axles? And for the engine I will probably end up buying a built one since mine has such high mileage, so for the crate engines should I be looking more for a Carbureted engine? To my knowledge they give about 10HP less than fuel injection, but I am finding a bunch of them from various sites and they are fairly cheap, from $6-9k. I also found an LT1 383 on Golen rated at 500HP for $7499 at https://golenengineservice.com/lt1-p...-block-engine/ And this is the long block, but the image has no intake and the specifications don't mention one. So my question about this is: will I need to get a new intake? could I use my old one? or will I need a carburetor for this? And would it be smart for me to have custom long tube headers made? I'm not sure if the 383 will have more exhaust than the stock lt1 and if new long tube headers would help that and improve performance. Also: 1995_LR mentioned something about a converter, I don't know what this is. And would this be a necessary item for a crate engine, or only if I were to do the conversion to 383? Thank you both so much! |
Re: 94 z28 stock lt1 to 383
$10k to do all of this will be a stretch unless you are doing some of this yourself.
Converter - torque converter. AKA stall converter. You're probably going to be looking at a 3200 stall, and a good one is about $700-$900. Yes, you will need one. Rear end: New differential. I run a TruTrac and love it to death. Good gears (AAM is about the best) and new axles and bearings. You're looking at about a grand in parts and another $500 to assemble everything and set lash on the gear. Engine: No need to carb it. The stock intake is 100% fine for what you want to do - and well beyond. If you get the heads and cam from Lloyd, have him also handle the intake. A complete port-matched system will knock your socks off. You also make no mention of brakes. All that go-fast stuff needs to go-slow just as quickly. |
Re: 94 z28 stock lt1 to 383
Originally Posted by 1995_LR
(Post 7002482)
$10k to do all of this will be a stretch unless you are doing some of this yourself.
Converter - torque converter. AKA stall converter. You're probably going to be looking at a 3200 stall, and a good one is about $700-$900. Yes, you will need one. Rear end: New differential. I run a TruTrac and love it to death. Good gears (AAM is about the best) and new axles and bearings. You're looking at about a grand in parts and another $500 to assemble everything and set lash on the gear. Engine: No need to carb it. The stock intake is 100% fine for what you want to do - and well beyond. If you get the heads and cam from Lloyd, have him also handle the intake. A complete port-matched system will knock your socks off. You also make no mention of brakes. All that go-fast stuff needs to go-slow just as quickly. As for the heads if I get them with the Golan crate engine they will be done up and pretuned I believe, so I guess all I would need is to have my intake done As for the brakes, I am looking into C5 brakes, but yes I will do that as well as I do enjoy stopping Haha. |
Re: 94 z28 stock lt1 to 383
I found a 2800-3200 lock up one for 4l60e that's only $400, for the torque converter would it be recommended to go the extra mile and spend more on a better one? I dont know if this one is bad per se, but just want to get everything right the first time.
https://www.monstertransmission.com/...l#.XLYU2DcpCdM I'm probably going to start with the rear end, upgrading 3rd member and the axles, upgrading the brakes, getting bigger wheels and tires and then I will save up and buy the engine and transmission rebuilt kit and torque converter, and have the intake sent off. Then I will put it all together at one time and throw it in. |
Re: 94 z28 stock lt1 to 383
A $400 converter will do little other than add a lot of heat to your ATF, and perform poorly. I have run a Boss Hogg (another $400 converter) a Yank as well as an Edge converter. The latter two were about $900, but both introduced less heat than the cheap one, and both performed almost like stock until romped on. I threw out the 3200 RPM stall based on my assumption that your cam and gear would be close to mine. Once things start being built, that may change. Your engine builder and your sales consultant from Yank or Edge can further guide you.
I would strongly suggest that you throw the brakes on and learn a lot more about what your options are and the implications of the choices you are making. A car is like a body - you can't change one part without affecting the whole so your choices need to be made from a holistic viewpoint. IE: increase the horsepower and you'll increase heat. This means you now have to upgrade the already crappy cooling system in the f-body. Increase stall speed and add heat, so you'll have to add a trans cooler. More gear means more torque so you'll probably have to upgrade your mounts, driveshaft, and brakes. More cam and heads means better exhaust. More cubes, cam and heads also means more air required and bigger injectors. All of those mean a custom tune is mandatory. Now that you're tuning, what else needs to be done to the tune? Lower fan turn on temps? Adjusted shift points and firmness? Less timing for a more conservative (city-friendly) engine? And down the rabbit hole you go. Since you're kind of new at the game, there is a LOT of potential to be relieved of money that you normally need not spend. This forum is ok, but kind of dead. Go over to LS1 Tech and the LT1 subforum and do some reading, and then head over to the Impala SS forum and read some more. LTx Tech is yet another one - and Lloyd Elliot himself regularly posts there. |
Re: 94 z28 stock lt1 to 383
Originally Posted by 1995_LR
(Post 7002494)
A $400 converter will do little other than add a lot of heat to your ATF, and perform poorly. I have run a Boss Hogg (another $400 converter) a Yank as well as an Edge converter. The latter two were about $900, but both introduced less heat than the cheap one, and both performed almost like stock until romped on. I threw out the 3200 RPM stall based on my assumption that your cam and gear would be close to mine. Once things start being built, that may change. Your engine builder and your sales consultant from Yank or Edge can further guide you.
I would strongly suggest that you throw the brakes on and learn a lot more about what your options are and the implications of the choices you are making. A car is like a body - you can't change one part without affecting the whole so your choices need to be made from a holistic viewpoint. IE: increase the horsepower and you'll increase heat. This means you now have to upgrade the already crappy cooling system in the f-body. Increase stall speed and add heat, so you'll have to add a trans cooler. More gear means more torque so you'll probably have to upgrade your mounts, driveshaft, and brakes. More cam and heads means better exhaust. More cubes, cam and heads also means more air required and bigger injectors. All of those mean a custom tune is mandatory. Now that you're tuning, what else needs to be done to the tune? Lower fan turn on temps? Adjusted shift points and firmness? Less timing for a more conservative (city-friendly) engine? And down the rabbit hole you go. Since you're kind of new at the game, there is a LOT of potential to be relieved of money that you normally need not spend. This forum is ok, but kind of dead. Go over to LS1 Tech and the LT1 subforum and do some reading, and then head over to the Impala SS forum and read some more. LTx Tech is yet another one - and Lloyd Elliot himself regularly posts there. Thank you very much for the links, I'm going to continue reading more on those forums. I've read some of every section on this one already. |
Re: 94 z28 stock lt1 to 383
My $0.02,
Do the rear end & gears/tires first. Easy to spend money here. I've not had good luck with the 7.5 rears but others have, YMMV. Grab logging/tuning software like eehack/tunerpro and DIY the speedo/trans calibrations. Get familiar with the software. Install trans temp, oil psi, and WBO2 gauges Make sure brakes/suspension are up to snuff then worry about upgrading the drivetrain $$$ etc... Read lots. |
Re: 94 z28 stock lt1 to 383
Originally Posted by Rhansen
(Post 7002502)
My $0.02,
Do the rear end & gears/tires first. Easy to spend money here. I've not had good luck with the 7.5 rears but others have, YMMV. Grab logging/tuning software like eehack/tunerpro and DIY the speedo/trans calibrations. Get familiar with the software. Install trans temp, oil psi, and WBO2 gauges Make sure brakes/suspension are up to snuff then worry about upgrading the drivetrain $$$ etc... Read lots. I want to put 17 or 18 inch rims, 8 inch wide on front and 10 on back, but that can come later as I'm sure I'll spend over 1k on rims and tires. I want to rebuild the transmission with the monster in a box kit and go ahead and do a shift kit on it while I have it apart and I feel like that alone will increase performance, as I'm having some negative thoughts about this transmission right now. When I get up to 50mph i hear what sounds like a shuttering sound, and when I let off the gas it immediately goes away, and when I am on the brakes slowing down coming to a stop light, right when it finally stops theres a clicking noise, the only way I know to describe it in words is that it sounds like plastic cracking I guess. Just one click though. And twice now it has slammed into reverse, and then it does it againwhen I go back into drive from that reverse. So I just wanna make sure it's done right, he said it was rebuilt 10k miles ago and he had to have him do it twice because it wasnt running right the first time so my guess is crappy mechanic. So my next questions would be: aside from rims tires brakes suspension that I plan to do, would I need a new torque converter when I rebuild my transmission (monster site says I do, but if I'm not increasing engine power do I really need one? And if so what stall would be best for stock lt1, and non lockup or lockup? I don't fully understand the stall/lockup parts. I believe the lockup would be better for heat reduction, but worse for top speed and gas mileage. Please correct me though. And lastly, what should I do exactly as to upgrading my rear end? I'm sure I can leave it as the stock 7.5 10 bolt for now, but I know I'll need a stronger one for a bigger and badder engine, so would I have to completely change the rear end to change to either a 12 bolt or to a Ford 9 inch? Or could I just get pieces parts, like get better axles and the gears themselves and then a different housing? I doubt it just looking at them. Thanks again. Sorry for having a lot of questions, and I'm trying to answer them myself with research, I just have little time right this moment as I'm working full time and in school full time in evenings so just asking for general information from you guys first. |
Re: 94 z28 stock lt1 to 383
The best method in building a car's driveline is back-to-front, so you are on the right track. The 7.5" is unfortunately a grenade when pumping anything more than 400 tq. Why they put that POS in the Z is beyond me. Luckily, us ImpySS/Caprice guys got the 8.2 & 8.5. There are options other than the 12 bolt and 9 inch. The 10 bolt 8.x is stout.
Here's a good, but pricey option that is bolt-in: https://www.hawksmotorsports.com/haw...-end-assembly/ The Ford will be even more expensive. They are cool though with the fast ratio-changes. I would not bother with the stall selection until you've got the engine sorted. Ideal stall speed is a combination of your engine's powerband and your gear. |
Re: 94 z28 stock lt1 to 383
doritoboy...
you have a long list. Golen makes a good motor. I bought a 383 4 bolt forged short block from them and have about 35k mi on it now. Call them and speak with Chad about your goals. Have Lloyd Elliott do heads/cam package and port match the intake. Tuning....need to source someone. There are still a few ideally someone on this site can recommend. I used Ed Wright but not sure if he is still doing them anymore. If so it would be mail order as I know he sold his shop years ago. Your tuner will advise on injector size based on what cam/heads you go with. Likely something of 30-36 lb Gearing. For a A4 3:73 is as low as I would go. If its not going to be a drag car than 3:43's would get you lower RPM's at FWY speeds. There are online RPM calculators you insert tire size and rear gear and tranny 411 and it will give you RPM at x speed Torque converter. Absolutely replace if rebuilding the tranny. Stall will depend on cam selection. Don't cheap out on the stall. Get a good one. Edge and Vigilantly have good reputation. Absolutely plumb in a external trans cooler. Rear end...the 7.5" is fragile behind power AND hard launches with a tire but for just driving it will hold up. Obviously going 9" will be a huge upgrade but if you are not going to drag the car the 7.5 should hold up |
Re: 94 z28 stock lt1 to 383
For tuning, this is a good source:
Moe Bailey MoeHorsepower Tuning San Antonio, TX 254-644-2656 I sent a very demanding buddy of mine to him for a mail order tune on a 1997 30th SS convertible with basic mods -cam, rear, etc., and he couldn't believe the improvement over the tune from an unknown source that was in the car when he bought it. He thought his only problem was the shift points being set to high, but when he installed the PCM, it not only shifted great, but it had way more power. He hangs out on ltxtech.com, and tunes for several of the top dogs at the LTx Shootout. |
Re: 94 z28 stock lt1 to 383
Originally Posted by Injuneer
(Post 7002663)
For tuning, this is a good source:
Moe Bailey MoeHorsepower Tuning San Antonio, TX 254-644-2656 I sent a very demanding buddy of mine to him for a mail order tune on a 1997 30th SS convertible with basic mods -cam, rear, etc., and he couldn't believe the improvement over the tune from an unknown source that was in the car when he bought it. He thought his only problem was the shift points being set to high, but when he installed the PCM, it not only shifted great, but it had way more power. He hangs out on ltxtech.com, and tunes for several of the top dogs at the LTx Shootout. Again, I'm super new to everything about cars. I was a nuclear mechanic that made a 1,092 foot long, 90,000 ton displacement aircraft carrier move lol. I understand certain physics and components of cars, but the electrical system is above me, and a lot of other specific stuff is still above me as well. I know tuning used to be about the carburetor, but now it's done through the car's computer. |
Re: 94 z28 stock lt1 to 383
Typically the tuner has a form you fill out listing all the mods, or not, you have. Tire size, rear gear, cam, injector size, etc. Certainly email or phone contact to fill in any gaps & ?'s
You mail him your PCM and he "flashes" it with a new tune based on your build. Some tuners offer a loaner PCM where they send one to you and you return yours as a core If doing your build in stages....you can get a tune for what you have now and then revisions as you add mods...that can get expensive if you do this several times Some even email you a file you install if you have the correct cable and software. Call Moe, he will fill you in |
Re: 94 z28 stock lt1 to 383
Originally Posted by Chimera96
(Post 7002666)
Typically the tuner has a form you fill out listing all the mods, or not, you have. Tire size, rear gear, cam, injector size, etc. Certainly email or phone contact to fill in any gaps & ?'s
You mail him your PCM and he "flashes" it with a new tune based on your build. Some tuners offer a loaner PCM where they send one to you and you return yours as a core If doing your build in stages....you can get a tune for what you have now and then revisions as you add mods...that can get expensive if you do this several times Some even email you a file you install if you have the correct cable and software. Call Moe, he will fill you in I have another question about the LT1 engine, is there any performance boost to be had with the engine without FI or Stroking it? As in can I have anything done to the heads/intake, long tube headers, anything internal, and obviously the tuning, to make it have more power? And if so, what is a max power I'm looking at? I know they were said to be about 275HP stock, 25 years ago. So would doing anything like this add anything substantial? Or would stroking it be my best bet? Thank you all again. Sorry for asking so many questions, I just want to know things lol. And I'm simultaneously reading other posts and reading the Gilles manual and the Haynes engine performance manual. So I'm trying lol. I just feel asking specific questions on a page with people who have done these specific things will help me better understand and cut to the chase. |
Re: 94 z28 stock lt1 to 383
Originally Posted by doritoboy100
(Post 7002664)
So how exactly would it work? I send him the chip or something?
Again, I'm super new to everything about cars. I was a nuclear mechanic that made a 1,092 foot long, 90,000 ton displacement aircraft carrier move lol. I understand certain physics and components of cars, but the electrical system is above me, and a lot of other specific stuff is still above me as well. I know tuning used to be about the carburetor, but now it's done through the car's computer. |
Re: 94 z28 stock lt1 to 383
Originally Posted by Injuneer
(Post 7002670)
The last year LT1 computer that had a removable chip was 1993. 1994 and up have a programmable chip that's soldered in. You have to flash-tune the PCM. As noted above, you ship the PCM. Some tuners will email you the tuning file, and the software required to download the tune from a PC, You buy a cable to connect from the PC to the DLC connector under the was, and download the program into the PCM. Personally, I would recommend just sending the PCM.
|
Re: 94 z28 stock lt1 to 383
OP
while cubic inches will make more power...the real power is in the heads & cam. Combined with a 383 bottom end a good H/C package will make for one strong motor....but you will need all the "supporting mods" to allow the new motor to perform optimally. These include tuning PCM, larger injectors & TB, lower rear gears, Torque Converter, Beefed up automatic tranny, larger in tank fuel pump (255 walbro) headers and or CAT back larger exhaust. If your current motor is still in good shape you can do a H/C package with a tune and it will have significantly more HP than a stock motor. However adding a new cam and heads in a old motor with original cam and rod bearings now dealing with higher RPM use....things can go down hill quickly. If your motor has 100k mi on it....I would rebuild the bottom end before adding H/C. You may, after machine shop goes through motor, get away with a re-hone on cyl walls, new rings. Have crank polished and rods re-sized for ARP fasteners and new cam, rod and crank bearings. This assumes your motor cyl walls check out good and just a hone/re-ring will bring it back. Ifcyl walls need to be bored .030 over than you would need new pistons but could still use your stock crank & rods. This would be a 355 motor |
Re: 94 z28 stock lt1 to 383
For more accurate and detailed descriptions of the various vehicle, engine and control components/systems, download a free copy of the factory service manual for the 1994 model year. More info, and more accurate than Haynes or Chiltons.
http://www.mediafire.com/?40mfgeoe4ctti Might want t go back and read through the first few responses to your questions, including - "WHAT IS YOUR BUDGET" (post #4) and "HP GOALS" (post #5). These are closely related. Yes, you can build a 750 HP naturally aspirated LT1 using NASCAR SB2.2 heads, etc., but if you don't have $15,000 - $20,000 for the engine, no point in trying. You really need to focus on what you are going to use the car for, as well. Is this: - a quick daily driver, for occasional stop-light drags? - a dedicated drag strip performer, seldom driven on the street? - an Auto-X/road race application? Each one of those has different requirements with regard to the chassis, suspension, engine, and drivetrain. It will help you home in on what you want, so we can give you more specific advice.. |
Re: 94 z28 stock lt1 to 383
Originally Posted by Injuneer
(Post 7002673)
For more accurate and detailed descriptions of the various vehicle, engine and control components/systems, download a free copy of the factory service manual for the 1994 model year. More info, and more accurate than Haynes or Chiltons.
http://www.mediafire.com/?40mfgeoe4ctti Might want t go back and read through the first few responses to your questions, including - "WHAT IS YOUR BUDGET" (post #4) and "HP GOALS" (post #5). These are closely related. Yes, you can build a 750 HP naturally aspirated LT1 using NASCAR SB2.2 heads, etc., but if you don't have $15,000 - $20,000 for the engine, no point in trying. You really need to focus on what you are going to use the car for, as well. Is this: - a quick daily driver, for occasional stop-light drags? - a dedicated drag strip performer, seldom driven on the street? - an Auto-X/road race application? Each one of those has different requirements with regard to the chassis, suspension, engine, and drivetrain. It will help you home in on what you want, so we can give you more specific advice.. My latest questions are to try and see if I can condense my spending, use the stock engine instead of purchasing a new one, and still meet my HP goals. I like the idea of stroking the engine, and if I'm not completely mistaken, if I bore the cylinder out 0.030 over, and convert it into a 355, and have the heads and intake sent off with the block, and get a better cam, along with a better torque converter and my transmission rebuild, and obviously the injectors maybe fuel pump and gas tank, and the PCM. But would I later be able to replace the crank shaft and I guess piston rods to stroke it to the 380? Basically take it in 2 steps? But have it drivable and still an increased HP than stock until I can fully stroke it. |
Re: 94 z28 stock lt1 to 383
400 rwhp w/o a power adder would be easier to achieve with more cubes (stroker). A 350 ci will need more rpm to see the same hp.
Originally Posted by Chimera96
the real power is in the heads & cam
Originally Posted by doritoboy100
But would I later be able to replace the crank shaft and I guess piston rods to stroke it to the 380? Basically take it in 2 steps? But have it drivable and still an increased HP than stock until I can fully stroke it.
Stroking the motor will increase static compression so you will want to keep this in mind when having head work done (chamber volume), especially if you plan on running pump gas. You might be interested in this thread (low buck stroker build) https://speedtalk.com/forum/viewtopic.php?f=1&t=42988 |
Re: 94 z28 stock lt1 to 383
.
You really need to focus on what you are going to use the car for, as well. Is this: - a quick daily driver, for occasional stop-light drags? - a dedicated drag strip performer, seldom driven on the street? - an Auto-X/road race application? Each one of those has different requirements with regard to the chassis, suspension, engine, and drivetrain. It will help you home in on what you want, so we can give you more specific advice. .[/really consider what he said above , i built a 383 all forged , cost a little over 6 grand with everything to let in breath right , should be approx 500 hp, according to similar builds. 280 xfi cam 58 mm throttle body, 12 to 1 compression ish 30 lb injectors, trick flow 21 degree heads 180 cc ported a little, headers 1 5/8" maybe 1 3/4" forgot.....getting old i guess. but i love it , sounds race even with the bigger quieter mufflers....it rumbles , instant tire smoke and breaks tires loose at 45 mph at least, i went through too many 4l60e transmissions and rebuilds so i switched to a 4l80e(a junkyard 4l80e is still holding up,$100) and aftermarket trans controller...no problems with it now controller was $200 additional from ebay(the older gm 4l80e controller) all i really need is better brakes to make it complete for "my needs". and i think thats what he's saying..... now..... this is just a little info on what makes me happy with my car , i think building a 150 mph car that handles like it's on rails might be a bit much for somebody that's used to speeding along at 30 knots in a boat ! lol ..........jk i know it's an aircraft carrier,] |
Re: 94 z28 stock lt1 to 383
Originally Posted by LT4orbust
(Post 7002684)
.
You really need to focus on what you are going to use the car for, as well. Is this: - a quick daily driver, for occasional stop-light drags? - a dedicated drag strip performer, seldom driven on the street? - an Auto-X/road race application? Each one of those has different requirements with regard to the chassis, suspension, engine, and drivetrain. It will help you home in on what you want, so we can give you more specific advice. .[/really consider what he said above , i built a 383 all forged , cost a little over 6 grand with everything to let in breath right , should be approx 500 hp, according to similar builds. 280 xfi cam 58 mm throttle body, 12 to 1 compression ish 30 lb injectors, trick flow 21 degree heads 180 cc ported a little, headers 1 5/8" maybe 1 3/4" forgot.....getting old i guess. but i love it , sounds race even with the bigger quieter mufflers....it rumbles , instant tire smoke and breaks tires loose at 45 mph at least, i went through too many 4l60e transmissions and rebuilds so i switched to a 4l80e(a junkyard 4l80e is still holding up,$100) and aftermarket trans controller...no problems with it now controller was $200 additional from ebay(the older gm 4l80e controller) all i really need is better brakes to make it complete for "my needs". and i think thats what he's saying..... now..... this is just a little info on what makes me happy with my car , i think building a 150 mph car that handles like it's on rails might be a bit much for somebody that's used to speeding along at 30 knots in a boat ! lol ..........jk i know it's an aircraft carrier,] I am probably going to end up sending the block off and the heads, replace the cam and stroke it, get long tube headers, upgrade the transmission and rear axle, get 18 inch wheels, around 8 inch front and 10 inch back minimum, and send off the PCM for tuning and see what injectors and fuel pump I'll need. 500 hp at the flywheel is good enough for me, more will always be better though. Thank you for sharing, this helps me a lot. And my ship topped out at i believe 70 knots, 40mph, pretty fast for a giant steel island carrying up to 98 jets/heli and ships company of 2000 people, and air wing of 3500 people. Just imagine the torque on those 10 foot wide bull gears turning those shafts! |
Re: 94 z28 stock lt1 to 383
This guy can build a 4L60E capable of reliably handling 1,000+ HP. Prices for a 500 HP build are very reasonable, given the quality parts he uses. No need for a shift kit.... that can all be taken care of in the PCM programming.
https://cahallperformancetrans.com/4...ds-%26-pricing |
Re: 94 z28 stock lt1 to 383
Originally Posted by doritoboy100
(Post 7002689)
And my ship topped out at i believe 70 knots, 40mph, pretty fast for a giant steel island carrying up to 98 jets/heli and ships company of 2000 people, and air wing of 3500 people. Just imagine the torque on those 10 foot wide bull gears turning those shafts!
|
Re: 94 z28 stock lt1 to 383
Originally Posted by Chimera96
(Post 7002696)
...ah 70 knots....that is 80.5 MPH..... unless you were on some secret carrier, More like around 30 knots. Carriers can't do 70 knots and if they could they would out run their support group
|
Re: 94 z28 stock lt1 to 383
Originally Posted by Injuneer
(Post 7002695)
This guy can build a 4L60E capable of reliably handling 1,000+ HP. Prices for a 500 HP build are very reasonable, given the quality parts he uses. No need for a shift kit.... that can all be taken care of in the PCM programming.
https://cahallperformancetrans.com/4...ds-%26-pricing I am going to get estimates on having my engine done, maybe someone that does heads and intake and the block all at one will give me the best deal. But aside from transmission and engine I will still need to send off my PCM and will have to worry about my rear end, will want better rims and tires too as I can barely hold traction as it is much less doubling my HP. I will probably end up selling my subs and amp and replace it with a cheap radio and get a stub antenna, I have an $800 stereo system in my car right now and I dont need it lol. Might remove my back seat too, remove a little weight. I also want to get the UMI shock tower brace, torque arm, drive shaft loop, shocks and springs, and their stage 2 front end kit, as well as long tube headers and C5 brakes so I can stop this monster. I have a lot of people recommended the same person for my heads and intake, so I will probably go along with that as I would rather it be done right than save a little money. Might as well get a better cam as that apparently helps some too. This will take me a while but I am eager to see it through. |
Re: 94 z28 stock lt1 to 383
is this your first car your hopping up? wow.....i used to just put a bigger carb maybe headers at first , then i learned about what a cam and porting can do, if you can afford it .....it's a lot of what i'd do
|
Re: 94 z28 stock lt1 to 383
Originally Posted by LT4orbust
(Post 7002721)
is this your first car your hopping up? wow.....i used to just put a bigger carb maybe headers at first , then i learned about what a cam and porting can do, if you can afford it .....it's a lot of what i'd do
I am planning on having heads and intake done and getting a better cam, rebuilding my transmission and getting a better torque converter, and then having my PCM flash tuned. That alone should show substantial improvement over this 25 year old car. Along with bigger wheels, stronger real diff and new shocks and springs and a few other odds and ends. I would like to stroke it at some point. Though I do have a full LT1 engine in my carport, I might just do all the work on that one since it's already removed, and then keep this one stock. I have received a recommendation on who to send my PCM to, my Transmission to, and my heads and intake. I am probably going to go through with this first, and continue upgrading the car itself before hand, and then when I have the spare engine all beefed up and ready to go i will just swap it and the PCM and be ready to go. I know there is a huge list of things that have to be upgraded or repaired or changed, so I'm just trying to compile this list, get references as to who to get each part from or send each part to, and I'm planning this all around when it needs to happen and how much it will cost. |
Re: 94 z28 stock lt1 to 383
Alright guys, so I'm kinda dumb and forgot that I had a spare set of lt1 heads already ported and polished in my garage. And after looking a bit I've decided I'm going to send my spare block off to a local engine shop, and have it stroked. I'm going to order the edelbrock air gap intake and BBK twin 58mm throttle body, a little under a grand for both, and I'm waiting on compcams to tell me what cam and stall I will need with that setup with the lower and rear end work I plan to do to it.
Probably $800 for the full c5 brake conversion, $2400 for the UMI drive shaft loop, torque arm, shocks and springs, and front end kit, And I'm still trying to find out what I will need for the rear end, if anyone has any links or what they used that would be helpful. Might go the 8.8 route. And the transmission rebuild is probably going to run me $900, and im still looking at wheels and tires, right now I'm at $1300 but I'd like to go cheaper lol. So that's about $6500 minus the torque converter, cam, stroking the motor, bigger injectors, dyno tuning and anything else I'm missing. Oh and $500 for a new waterpump and optispark and new wires and plugs. Lol. Hopefully I may end up under 10k for this build! |
Re: 94 z28 stock lt1 to 383
I would save the $ and not get the Edelbrock intake. Just have a stock one port matched to your heads...you will also need the throttle body opening on intake machined to accept a 58 mm TB
IMHO I would reach out to Lloyd Elliott about a cam vs Comp Your TC choice will depend on cam and rear gears....don't cheap out on a torque converter. Any stall above 2400 get a external trans cooler Your 58 mm TB will likely need some modification to it to get the car to idle right which requires the ability to scan for IAC counts...whole long topic on that |
Re: 94 z28 stock lt1 to 383
What are the flow numbers on the ported LT1 heads? Hard to pick a cam without knowing that.
I second above comment on the Edelbrock Air-Gap intake. Offers nothing the stock intake doesn't already have, other than the red powder coat. In fact, the plenum volume has been sacrificed to create the "air gap". 58mm throttle body is really not required until you exceed 500 HP at the flywheel. My stroker made 496 HP on the engine dyno, and the shop showed me on the dyno that 52mm TB would have been able to supply all the air the engine needed. The power peaked with the 58mm TB only 77% open. Opening it further didn't change anything. They still laugh at my 58mm TB. |
Re: 94 z28 stock lt1 to 383
Hmmm, well I dont want to have something unnecessary. If 52mm will do then I'd rather get that or something right above it in case I ever want to add more power. I want to get at least 400rwhp, so 500hp at the flywheel is where I'm going to be around. I was looking into the ss hood and ram air intake, I can send my heads and spare intake that hasnt been ported off, I'm not sure what the specs on the heads are currently, but what would I need to attain the 500hp? I will message lloyd today, and if I can zero in on that I guess he can help me with the cam and stall himself.
I was told the edelbrock would help with head reduction of the air coming in, but I do have a spare intake lying around that I can toy with. 2, in fact. |
Re: 94 z28 stock lt1 to 383
and I thought it was a weekend car.....yup.... I am
|
Re: 94 z28 stock lt1 to 383
Have the heads flowed by a competent shop. You're looking for at least 280-290 CFM on the intakes, Closer to 300 CFM, the better. 195-200 CFM on the exhaust.
The throttle body bores on the stock LT1 intake manifold are 52mm. AS&M used to make a 54mm TB, not sure if they still do. The 54mm throttle body can be bolted to the stock manifold with minimal flow disruption. REVISED TO CORRECT ERROR ON STOCK INTAKE MANIFOLD BORES |
Re: 94 z28 stock lt1 to 383
Originally Posted by Injuneer
(Post 7002759)
Have the heads flowed by a competent shop. You're looking for at least 280-290 CFM on the intakes, Closer to 300 CFM, the better. 195-200 CFM on the exhaust.
The throttle body bores on the stock LT1 intake manifold are 54mm. AS&M used to make a 54mm TB, not sure if they still do. |
| All times are GMT -5. The time now is 10:16 AM. |
© 2024 MH Sub I, LLC dba Internet Brands