Hi there!

I'm looking for a way to upgrade my LT1 engine to get street car with 350+ RWHP. The car is now and will be everyday driver, definitely not a track car or maybe one or two times.
Now it's something knocking in there and it waits for a rebuild.
Today's setup is stock LT1 with Powerdyne BD-11A supercharger that will be deleted cause of it is very unreliable. Also stock 4L60E but with some Sonnax part in it and I want it to stay it like this at least for the first times.

So I need your advices for choosing a parts for my future setup. As I live in Ukraine the part will be bought predominantly via the Internet in the USA (jegs/summitracing/rockauto/amazon/ebay etc.).
I'm think that i need: heads and camshaft package, intake, throttle body, all the valve train, injectors, rockers, lifters, push rods, fasteners, forged pistons and rods, bearings, maybe timing kit, forged crankshaft, main mearings, maybe a balancer or leave it stock idk, think long tube headers. Need your advice on what excact parts I should buy for my setup according to your setups and experience. Maybe it will be supercharged again in few years after the rebuild so I need to go with strong parts.
All job will be done in the shop with my time to time personal assistance.
So what setup is good to go?

Thank you in advance.

 

For just 350 RWHP a mild cam and good heads in a solid short block will do that. Yes you will need 30 lb injectors (Ford red tops) and a PCM tune. Your stock Throttle Body would be fine

Look into Lloyd Elliott at Elliott Portworks for a head & cam package a 218/224 (or even smaller) cam will be fine a very streetable

cam: LT1 Cam Info «
head: LT1 LE1 «

The motor rebuild...assuming there is not a shop where you live that has the parts or experience in rebuilding the LT1 than you could buy a basic short block from Golen. They likely offer a basic 355 rebuild also. I have had one of their 383 short blocks for years now, no issues

Golen: https://golenengineservice.com/lt1-performance-engines/

or if you want to rebuild your short block than you would need to confirm the cyl do not need a over bore of .030 which means new pistons and it would then be a 355 C.I. motor. You would need to get all new bearings, pistons/rings. Have the crank polished or ground .0x0 under. Have the stock rods resized and fitted with ARP fasteners. New timing gear set, oil pump, gaskets

 

Difficult to answer your question:

- What is the condition of the engine}? How many miles (km)? Does it need a rebuild?

- What grade of fuel is available in Ukraine? What octane rating system is used? In most of Europe they seem to use “research octane” which is typically in the range of 95-98 octane. But in the US we use (research octane + motor octane) divided by 2. That generally means 92-93 octane in the US is equivalent to the research octane 95-98 posted on pumps in Europe.

- What is the elevation above sea level where you live? That has a major impact on compression ratio and cam selection.required to meet a specific HP goal.

- You have two very different specifications. 350+ rwHP is vague.... how big is the + ?

- 350 rwHP through a 4L60E requires about 425 HP at the flywheel. That's really easy on a stock bottom end in good condition. But 500 flywheel HP (415 rwHP) is a bit more demanding. Which is it, or something in between?

- Then you add another issue - you may add a supercharger in the future. That requires a much different engine build, starting with compression ratio, cam specs, piston selection, fuel system capacity, etc. Just what HP level are you possibly looking at? You can get to 1,000 HP+ with the right components. But that is a huge difference than a normally aspirated engin built for 425 HP.

 

Thank you for your replies!
It seems me it will be a long read.

It will be more preferably for me to not to buy a short block because of its weight and future customs difficulties in my country. It is more easier to buy and ship parts as parts.
Roger that. But how do you think is it possible to tune the PCM remotely with some software by buying a firmware file from US tuning shop? Or should I buy a whole '95 Z28 PCM with already upgraded firmware?
I was going tu buy a 58mm throttle body maybe from Edelbrock and also their LT4 like intake manifold cause they are match each other. It's for the future purposes, I don't want to throttle body and intake will become a bottle neck in the future. But I don't know will the intake manifold match those LE heads?
I think I should write them and ask about their package. I was wonder cause before I write my first message in this thread I did some searches though this board and found several similar threads and most of them recommend these LE heads and cams as a good to go setup but almost all of those messages were written from 2002 to 2008 and it is about ten or more years last and these heads are still one of the best options. Is that truth?
I think that you actually have a point... Our shops can rebuild almost anything that can be named internal combustion engine but it's thruth that they are not familar with US built V8 engines cause of their rarity in my city and my country as well. So I will be a parts provider and also will try to provide all the possible instructions about the tightening torque or measurements that will be required for the LT1 engine.
So my plan is (correct me please if I wrong):
- get the car to the shop (I can do it )
- pull out the engine (my shop mechanic with my support)
- disassemble the engine (my shop mechanic)
- do all the necessary measurements to find out exact conditions of the all internal parts (heads, valvetrain, push rods, pistons, rings, block cylinders, all the bearings and crankshaft etc) (my shop mechanic)
- write down the task for machine shop according to LT1 engine rebuild documentaion to do a machine job (of course if needed) (my shop mechanic)
- order parts according to the machine shop's results (pistons for rebuild size for example etc) (this lies up on me)
- order other parts according to your recommendations (this is my function too)
- put all of these together (my shop mechanic with my support)
- pull the engine in (my shop mechanic with my support)
- tune the PCM (probably someone from the US tuning shop with my hands, but idk)
Roger that! Because of the unknown history, mileage and condition of my engine I probably prefer to by all new parts and buy them strong for future setups, maybe I should by a forges crankshaft too. How do you think?

Unfortunately we don't know, Sir! The car was bought with 113k miles five years ago and now has something about 127k miles. The engine was running normally all the way (except its dynamic, as you may remember I was complaining for bad acceleration even with s/c installed), but several days ago something started to knocking inside the engine and it looked like it is one of the piston rods so I stop to use the car and decided to rebuild the engine and refresh it with some sporty parts and HPs. A Previous owner ot the car told me that his mechanic reringed pistons as those rings are worned out, but this info can't be proved or disproved for now. So I tren do think that this engine will require some rebuild.
Yes you're right - in our country the research octane is used. So I usually use a so called 95th type of gas that is accords to the US 90 octane gas but most of gen-1 small block guys in Ukraine fill their Suburbans, Tahoes and Caprices with our 92nd gas that is similar to the US 87.5 octane. Our 98th gas is used by highly boosted modern cars such as Subaru Impreza STI or Mitsubishi Evo, and this type of fuel is similar to the US 93 octane.
I live in the so called prairie area and it's sea level is about zero, so most of the rides my car does between 50 meters up and 50 meters down or even narrower.
It depends on the parts I have to buy and my budget. If my budget will be able to build only 350-360 RWHP I will be satisfied. If more - than I will be at the seventh heaven. But I remember that the car must stay streetable and behave to my stock transmission and ten-bolt gently.
Yes, Sir. Something in between but more nearer to 425 HP at the flywheel as I want to use the car most of every day in my city and it means that I should crawl through the traffic jams sometimes or park in some narrow areas time to time.
Yes. But I have a supercharger now that can do about 350 to 400 HP with my stock block, so I think that a new supercharger will let me get some more 100 HP over that block that I want to build now. And definitely not, I don't want to get 1k HP cause I don't want to convert my street daily to a track only car.

The most that scares me is the parts matching that I must do well before to order them.

 

It comes down to three different engines.... and you indicate it depends on budget. There's really no way someone in the US can estimate the cost of building the three different engines in Ukraine.

The first one is easy - 350 rwHP.. Read what Chimera posted. That is the correct answer. Replace the timing set and the damper (it is not a balancer) only if they show signs of wear.

Heads & Cam - surprised you couldn't find a recent reference to LE (Lloyd Elliott). There are two reliable sources of ported LT1 heads. I recommend them all the time, definitely more recently than 2008.

http://elliottsportworks.com/

Advanced Induction - LTx Performance Parts

In both case, in the US, you send them your LT1 heads and intake manifold, and they port them. Since you aren't in the US, you would probably have to let them supply the LT1 heads and intake for an additional cost. You also need to contact them to see if they will even ship outside the US.

Stick with having the stock LT1 intake ported to match the heads, by the head porter. There is NO benefit in the Edelbrock intake, other than the red paint. In fact, one dyno test I remember from way back indicated that by raising the floor of the intake to make the supposed "air gap", they reduced plenum volume, which is a negative.

You can get by with the stock throttle body on the 350 rwHP build. A 52mm would be a small upgrade. It doesn't need a 58mm. When we were building my engine, the shop showed my, on the engine dyno, that even at 500 flywheel HP, the 58mm TB was not necessary. It flowed sufficient air at 77% open. Opening it further did nothing. Back calculating, a 52mm would be adequate. Depends on your budget. 58mm would be beneficial for a S/C setup.

The cam in the 350 rwHP build can be fairly mild, for streetability. At the 500 flywheel HP level, you can still drive it on the street, but it's going to be a bit less friendly. You would need a high stall torque converter, and 3.73 rear gears. But that isn't a "track car".... it's still a fun daily driver.

The recommendations you get from people here are going to assume you are running the equivalent of 92-93 US octane fuel ( (R+M)/2 ) If you want to run something less, you are going to have to give up HP.

For tuning, it's getting very hard to find good LT1 tuners, even here in the US. It may be possible for someone here to prepare the file, send it to you via the internet, along with the software required to load the tune into your PCM. Otherwise, you are looking at sending your PCM here to be tuned, and then returned to you. Again, tuners are hard to find (I feel I know a good one) but then you have to see if they will deal with shipping, payments from outside the US, etc.

The 350 rwHP rebuild can survive with the stock crank polish, resized stock connecting rods, and IF the cylinder bores doesn't require boring, the stock Mahle pistons. Worst case - if boring is necessary, you can still use hypereutectic aluminum pistons. Turning that into a 425 rwHP setup doesn't change much on the bottom end. Stock parts are up to it. But if you are going to S/C on top of that, you need a forged crank, stronger connecting rods, and forged pistons. A 4-bolt main conversion would be a good idea. But adding the S/C AFTER building it as a normally aspirated engine would require changing the pistons or the combustion chamber volume to drop the compression ratio a bit, and possibly a different cam.

A 1,000+ HP S/C build is good for the track, but it can be driven on the street very easily - I've done it with a friend's 30th SS convertible..

 

OP

don't get the Edelbrock LT4 intake or 58mm TB. Waste of $. Aftermarket TB's require "adjusting" ( read drilling a IAC hole and needing software to read IAC counts as you do this). Your 48mm TB will be plenty for a 350 RWHP, and more, car

I would buy this book and read it several times. It will greatly help you and your mechanic rebuild the motor

https://www.amazon.com/Rebuild-Small-Block-Chevy-Engines-Hp1393/dp/1557883939/ref=asc_df_1557883939/?tag=bingshoppinga-20&linkCode=df0&hvadid={creative}&hvpos={adpositio n}&hvnetw=o&hvrand={random}&hvpone=&hvptwo=&hvqmt= e&hvdev=c&hvdvcmdl={devicemodel}&hvlocint=&hvlocph y=&hvtargid=pla-4583863980119783&psc=1

You are not going to know the internal condition of the motor until it is torn down and measured. You "may" just need a re-hone on the cyl which means you could re-use your stock pistons and just put new rings. Otherwise a .030 overbore and .030 larger pistons. Mahle or SRP are good pistons. Just don't buy cheap heavy pistons with huge (thick) rings. Your crank may just need a polish but if you have a rod knock now it likely needs a .010 or .020 grind with new corresponding oversized bearings. Have the stock rods re-sized with ARP fasteners installed on them.

Lloyd Elliott is still regarded as a top shelf head porter and cam grinder so his combos will be very good. He could also send a match ported intake for the heads. You could ship him yours but it may be cheaper for him to provide one which would be a stock one he port matches to the heads

If your current motor with the SC was not tuned for it or you are still using the stock injectors it likely runs like a slow dog. With any head and cam package with larger injectors you absolutely need a PCM tune which is also based on your fuel octane availability. You can get a "mail order" where you ship your PCM and they reflash it or they provide you with a donor PCM they re-flash. Some tuners also can send you the file electronically but you need a laptop and cable to install it. Moehorsepower is one who I believe still does mail order tuning

 

Thank you for your replies, guys! The situation becomes clearer for me.

Ok, I understood. Let's try to concentrate on the first one. Let's name it Stage 1 within this thread. This will be the 350 RWHP engine but with use of strengthened parts if they suitable for future purposes. So why not to use forged pistons today if they may be reused in future when I will be ready to go to forced induction (I propose to name it Stage 2 if you don't mind) or this is not impossible or just a waste of money?
Yes, you're right, I have some budget to throw in to this rebuild. For me I divided it to three independent parts:
- Parts and tune up services that a I will buy in the USA (I'm going to invest from 3 to 5 grands depending on the resulting setup);
- Shipping expenses (it almost depends on the weight of the parts, for example it will be cost about $100 to ship a Hooker long tube headers straight to my home in Ukraine);
- Rebuilding the engine in Ukraine (the average cost of the engine rebuild in my country is about $50 for one cylinder, so it will be about $150 for disassembly and measurements and $250 for engine assembly, $150 for heads at the machine shop and $200 for the block to do a machine works).
Ok. Looks like it will be good to go. Will inspect the timing set when the engine will be pulled out.
I found their website a week ago when met a mention of their service in one of the old threads on this board for the first time.
Yepp, it will be the best way to buy a package that is already matches all the parts in it to each other.
And it is not necessary to the shop to ship their parts to Ukraine, it will enough to ship them through the US to one of my post office boxes that i located in Port Reading (NJ) or Newport (DE) and then my delivery company will ship them to Ukraine, so I think that the overall shipping process won't be different as they ship to someone who lives in the US.
Ok with that. At least the process of replacing the throttle body doesn't look like difficult and affect any other parts than intake manifold.
It seems to me that it is not so bad idea to use the camshaft that will allow me to use my stock converter and my GU5 3.42 axle ratio at least for my Stage 1 upgrade.
I use 91 (US octane) gas for everyday rides it is the most common gas in Ukraine but it' ok to use a 93 US octane fuel, it is common for 2/3 gas stations in my city. At least my owners manual says that I should use a 91 octane gas for this type of engine with 10.4:1 compression ratio.
Understood that. Yepp, the file and software via the Internet would be a great solution for me and also it is not a problem to me to pay for these options via a PayPal or my credit card it is so easy now. Again it is not so difficult if they just sell their already tuned PCM for me and send it to my post office box as I mentioned above. These two options look much more preferable than to send them my PCM through the half of the world and then to send it back to me. I assume that it will increase the cost of this package by adding there a donor PCM but it's ok too.
Does it mean that I cannot use some forged parts already on my Stage 1 setup? Also I read that many people go to 383 stroker engine to use it with the supercharger. Is it related to dropping a compression ratio or am I wrong?
Nice to hear that but I'm afraid that I could easily run off the budget with that and also I think that I should to 'grow up' for such setup on my car.

Ok with that. Will try to run with stock throttle body and intake just get it ported to match heads as I understood from your and Injuneer's previous messages. At least it will save me some money and stock compatibility.
Thank you, this and also two other LT1/LT4 rebuild related books are already on their way to Ukraine!
Yepp, all of this will be known as we disassembly the engine and remeasure it well.
Oh, it definitely looks like a great solution for me to buy a whole upper package including an intake manifold already ported as I'm located over 6000 miles from Red Oak, TX.
Nope, my S/C setup is very old it is from those times when probably PCM tuning wasn't so good idea.
So my S/C setup consists of:
- supercharger head unit that is driven by the belt;
- a set of air ducts;
- a map sensor capable to measure pressures greater than 14PSI;
- a set of three additional injectors mounted between the throttle body and intake manifold;
- a driver for those injectors;
- a fuel curve generator located under the center console inside my car;
The logic is simple: engine rotates a supercharger that throws additional amount of air that creates a pressure greater than 14,6 PSI, a MAP sensor feel it and sends it to the fuel curve generator, which sees in his fuel tables and picks up appropriate amount of fuel to be added by injectors then it commands to the injector driver to open the injectors for some period of time. That's all the magic. But some one of the previous owners had replaced the air elbow and forgot to add the MAP sensor, thus the car's PCM stayed one to one with huge amount of air trying to compensate it with available amount of fuel through the stock injectors available. And just like you said my car became a slow dog. Also I rebuilt this head unit for the third time and it seems to me it is not for a long time cause it is very unreliable. That's the reason I want to delete this old S/C.
As I mentioned above, send the file with the software is the best way for me. It's not a problem for me to connect my laptop to the PCM in the way to upload a tuned firmware as I already has connected it several times to use Scabn9495 software to read and save logs. Also send me a donor PCM with the firmware upgraded is another good option. Moehorsepower? Do they have their own website or something I can use to contact with them? Thank you. Also I read that guys from the fastchip.com can do the job.

Another one question about those LE camshafts... Are those cams require stock LT1 hydraulic roller lifters or I should replace them with aftermarket ones?

 

stock lifters are fine....although most if not all cam companies recommend new lifters with a new cam. Inspect your lifters REALLY well and determine if they can be re-used if the rollers do not have any wear marks or chips in them

With that said I put in new lifters when I did my 383. Comp 850's

You likely will need new push rods because your heads and block will be decked from rebuild and cam profile is different. "Generally" shorter PR are needed but you need to measure to confirm first using a PR check tool.

Also many convert to guide plates vs using self aligning roller rockers. This is recommended for motors that will see higher than 5500 rpm use. I use Trick Flow chromoly hardened PR with .080 thick walls and ISKY adjustable guide plates with Comp Pro Mag 1:6 roller rockers. I also went with 7/16" RR studs vs the stock 3/8". Less valve train flex. The ISKY guide plates allow you to adjust each rocker separately vs the one piece guide plates

 

Ok, let's narrow the question: if I choose Lloyd Elliot as a head and intake porter and as a camshaft provider should I ask them for lifters to recommend or provide for their camshaft or just buy the new stock style roller lifters if my are worned out?
It looks like they may work with other stock components i.e pushrods...
Ok with that. Will buy a appropriate pushrod check tool.
Nice experience, but I think that I should go with hydraulic roller rockers for my so called Stage 1 streetable setup.

Is your 383 a naturally aspired engine or it has some forced induction?

 

Roller rockers come in either SA (self aligning) or NSA (non self aligning. The NSA ones require guide plates. Many feel motors that will see higher than 5500 rpm and use the SA RR they can "jump off" the valve tip so I and many others switch to NSA. Either one has nothing to do with hydraulic or solid lifters

My 383 is NA. I have around 40k mi on the motor now

 

Nowhere did he tell you to use anything other than a hydraulic roller lifter. What you quoted mentions the advantages of NSA (non self-aligning) full roller rocker arms in high lift applications. In fact, he indicated earlier he used the Comp 850 lifters, which are hydraulic rollers.

 

I'm sorry, I've made a mistake and mixed up different terms and parts and thank you for your attention and corrections. Some things are getting clearer for me now.
So now I have to summarize all these advices here into some approximate setup and post it here later.