Hello,

I'm a long time old member but I haven't been on here in maybe 8 years. I don't even remember my old user name but it's good to see this place still around. Ever since my LT1 bit the dust I put the car in storage as I couldn't make up my mind what to do with it (that and money trouble).

I’m finally back in a place where I can get back into playing with my car again so here’s what I need some help trying to decide and any input is appreciated.

I currently have a 95Z28 with LT4 AFR heads, ported GM LT4 intake, mildly aggressive came and chassis work galore done to my car. It was pretty much a race car that I used for street racing but could still pass inspection with it.

My Z28 means a lot to me and I have no plans of getting rid of it. I was looking at purchasing a GT500 or picking up a Salvage GTR and building it up but when I thought about My Z and how power she had before I started thinking about finishing what I started. If I got the GT500 it mostly would just be a weekend driver as I wouldn’t mod it. If I brought the GTR I would have a smile on my face everyday but I would still have to put money and time in it to get it back to what it should be.

When I started playing with the numbers on what I would be spending on either car ( I really just want to make something fast or enjoy something fast) I started to think about what I could do dropping some TLC into the Z28.

Now the block on my LT4 Uppered LT1 Block lower is done. I parked the car after my new cam and tune setup murdered my Opti on the first rev. but I also noticed some serious blowby. I was running the stock bottom end and promised myself if she ever took a dump I’d 383 and turbo the car of course my wishes and my finances didn’t match up.

So I’m pricing the parts to build the forged 383 I need and it’s about $6K. and then when I start putting ideas together I start to also realize that 10+ years have passed and LS1’s are cheap now but there’s also the LS3.

I was looking at the LSX376 crate GM has for around $5K which is built to handle boost and also makes about the same HP as a 383LT1. Selling the parts off my old motor I could probably make about $2,500.-$3,000. I do have my K member and stuff I could sell and aluminum drive shaft and other LT1 stuff that I wouldn’t need anymore to also help with the costs so it’s not a fruitless labor.

But I’m also aware that I have to get a new engine harness, PCM, and other LSX stuff to make the motor work. Either way it’s about 50/50 on this project. The motor still needs to come out and I still need to do an S-ton of work to it. I even thought about just getting the LSX block and stroking it out and building it up for turbo but I think I’d only save maybe 1 or 2 thousand on it doing it that way.

The only advantage I’d have by keeping my LT4/LT1 setup is sticking with the devil that I know. I would be able to build an damn near immortal forged LTX but would it be worth the effort knowing I could get more out of the LSX?

That’s’ what I’m stumped on. It’s hard not to think about going for an LS3 or LS1 or 2 when knowing those engines were purposely made to make yours obsolete. It was an HG leak that took the life of my bottom end but before that the only problem I ever really had with the car was killing Opti’s left and right (I swear I could change one blind folded in under 1 hour).

So what do you guys think? I’ve really open to some suggestions as I’m torn as to what to do. It be nice to either part out my LT1 and put the cash on an LSX but it also be nice to keep my LTX and throw the money on building the block up and relying on the forced induction to make up for what it lacks.

Thanks for all help.

 

Really?

Food for thought ---->> https://www.camaroz28.com/forums/par...-block-870670/

KW

 

Money wise, you'd probably be smartest to stick with the platform you have, cause not only would it cost quite a bit to get the LS1/3 in there by the time you were done, but you won't get that much for your old stuff cause the for sale section is full of people selling off their LT1 stuff. Performance wise, the LS3 would be awesome, but if you're going to go FI anyway (you mentioned boost), then you can still make more power than is usable with a LT1 if you want. Just don't build or buy a lower compression FI engine, then not go FI.

 

I *agree* with Kevin. Unless you won a built LSX motor through "Publisher Clearing House", or something, I could not imagine the swap would be worth it. If you can address the problematic Opti-spark issue (I went coil-on-plug), the LT-1 is actually a good platform. AND if you were going F/I, the big grin on your face will eliminate any doubt that staying with "Team LT-1" was the best decision. LOL!!

 

Most people that know me already know what I will say.

LTX!!!!


Just stayin true to the evil opti is all.


YES... it may be easier to go fast in an lsx.... but thats if u start with an lsx platform....



Larry (Popo8) Co-owner
LTXtech.com

 

I'd do the LSX is you have the funds and time to learn everything about swapping from LT to LS.

If your going FI with the LT motor you might as well ditch the LT PCM and do the LS PCM and coils, the LT PCM is junk when it comes to fine tuning and FI. That way you can have just about anyone tune your car too, nobody tunes LTs anymore.

 

Since the 4th gen platform was able to use either engine family and the crate engine is roughly the same cost as the mods you're thinking of, the only decision is what you want moving forward. I believe the crate engines come with a PCM and engine harness so you don't even have to sort that out. It's as close to a plug and play mod as you'll ever find...after you swap to LS specific stuff on your car.

With the LS family mods are pretty simple any more. want a supercharger? There's a kit for that...a complete kit including getting the PCM recalibrated.

The downside is that the car won't ever be worth anything if it's swapped to a different engine family. Of course, none of these F-bodies will ever be worth anything..chuckle.

Go LSX and don't look back. All you be missing is a good exhaust sound...LS cars sound like crap.

 

Thanks for all the replies Brings me back memories to how awesome and helpful this place was back when my car was still rolling .


I'm still in the undecided crowd. I'll probably start tearing the block apart with the "MadScientist" this weekend and then start figuring out on what I really want to do with it.Who knows... maybe I'll put a banana peel in front of some guys ZR1 and take his motor.

 

Yeah, that was part of my reasoning is that the LSX is going forward and it's only going to be easier to find stuff. GM has forsaken us and so has the aftermarket. They even forgot they already made an LT1 so now they're making another LT1.

Thing is some stuff I wanted to change like my K-member since the one I have I don't like. It started cracking and I had to reweld it.

 

I must really be out the loop. No one tunes LT's anymore. I can't remember who did the tune on my car last. I do remember running into lots of ignition problems after a while. I didn't know it was possible for the LS1 PCM to run an LT1 Properly. I thought they had difference sensors and stuff?

 

there are still plenty of tuners who tume ltx .

as many as there used to be???? no. But they are still out there.


Larry (Popo8) Co-owner
LTXtech.com

 

Most of the tuning is done via email tunes or shipping off the pcm to be flashed. The ltcc gets rid of the high power side of the opti and you can run coil per cyllinder. The 24x system allows using the ls pcm and a coil per cyllinder basically doing away with the opti and using ls tuning software. If your going boosted it might be the way to go if you stay with the lt platform. I opted for n2o as my power adder because I could have a dependable daily driver setup near 400hp to the wheels and with the flick of a couple switches add a 200hp shot. I went with the ltcc because it had timing retard function I can trigger with my n2o arming switch. Pretty much if your going to run a turbo or supercharger for sure then as said above go with lower compression but if you want higher compression then n2o is worth considering. I also picked up a nano pusher system for the spray as that adds some benefits to the nitrous but would have to manually open my bottle then. Personally you might be better off getting a ls based car if you go ls as long as you can say goodbye to your existing car.


Posted from Camaroz28.com App for Android

 

Op Im on tapatalk so i cant see where u are from.... but let me know and Im sure I can locate hands on tuners near u (may require a little travel) that KNOWS ltx tuning.


Im prob just a lil more in tune with it being the owner of an LTX specific site, but as previously said mail order tunes or email tunes are always available for simpler builds.


Larry (Popo8) Co-owner
LTXtech.com

 

You have to choose what you really want from your build. NA and boost can be worlds apart when it comes to engine building and you really need to keep your final power goal in mind when building any shortblock or swapping any motor. You already have half the parts needed to build a fire breathing LTX monster and to part it out would be a complete waste.

Why are you so obsessed with going forged? This is sort of thing is gratuitous and completely unnecessary for the street. The LSX376's bottom end doesn't really have that much of an edge on your current LTX. The only reason it's "built for boost" is because the pistons are forged rather than the hyperpathetics that are standard on most NA street cars. Like the LT1, the crank is still NODULAR IRON and the rods are still POWDERED METAL which is nothing fancy. Realistically, the only big difference between your LTX bottom and the LS bottom would be the forged pistons, added main bolts, and a marginal difference in displacement. Don't let the 2 bolt mains scare you, they can take a beating with some decent studs. If that still makes you uncomfortable then pick up a used 4 bolt Vette block for $200 or less.

That being said, how much power do you really want? You're have very little headroom left NA on the street. Boost it and don't look back.

My suggestion for a bargain basement build that could be boosted to a certain extent (I would feel uncomfortable over 550whp)...
Line hone your 2 bolt block and use ARP studs
Get stock crank turned and reuse
Get stock PM rods resized with ARP bolts and reuse
Loosen main/rod clearances from stock with fresh bearings
Upgrade spring in stock oil pump for higher pressure (not HV)
Hone block to 355
Install forged pistons but BE CAREFUL! Do not choose a piston with large valve reliefs or dishes because they have a tendency to cut too far into the top land and piston crown making them really weak (so when it detonates you will loose chunks on 4032 pistons easy)

Shoot for 9:1 scr and pick up a decent used supercharger. You will have no trouble making 550rwhp and beyond with your current heads and the right blower cam. You probably won't even have a stupid amount of boost because your motor probably already flows a ton with those AFRs.

If you want more than that then just swap out the crank for a 14088532 forged GM unit, add some cheapo 4340 Scat rods, and find a Vette block for not that much more. The bottom end will be rock solid.

And are you insinuating that nobody tunes LT1 cars anymore or something? It's OBD1 for christ's sake. You could tune the damn thing in your driveway if you really wanted. Read a book and buy an ALDL cable.

 

Again, nobody tunes LT1s. Go to any good performance shop and they will tell you no. Sure they can do it but they won't simply because of the opti. When I say tune I'm talking about a dyno tune. Mail order tunes are great for little bolt ons but when you start to make real power you need to have your car find tuned on a dyno or at the track by someone who knows what they are doing. The mail order tunes can be robbing you of a lot of power, not all cars are the same. They do their best but you just can't beat having the tuner on site fine tuning your car.

So right now there is a small handful of people doing mail order tunes and a few more tuning LT motors. Out of 10 tuners 2 will attempt to tune the LT1, out of those 2 only 1 will be able to tune the motor correctly. If you go FI good luck on the 1 guy tuning it right. Just think in 10 years when your a die hard LT1 fan (like I am) and its time to retune your car and nobody's there to do it, they will ask you is what year vett do you have and you have to hang your head in shame.

Call around to any shop from the east coast to the west coast and ask if they tune LT1s then ask if they tune LSx motors, you will get a yes and a no pretty consistently.