Hello all,

I recently acquired my fathers 1991 Camaro RS. The car has unfortunately been sitting outside under a cover for around 10 years and I am planning on restoring it. The vehicle currently has the stock 305 in it along with a 700r4 transmission with the B&M ratchet shifter that has been built to handle ~400hp along with a 2500 stall converter, as well as 3.73 gears in the rear end. I plan to swap an L98 350 TPI engine into it, which he pulled out of a crashed 1992 Camaro IROC along with the ecm. This engine was running when it was pulled out of the parts car, however it has been sitting for 10 years in the garage. I am very green to working on cars, as I have only done minor work on my 2018 Giulia along with some other minor stuff on friends cars, and I think this is a great way to learn the ins and outs of engine building as well as other parts of the vehicle. I want to rebuild the 350 to push around 300-350whp, and was looking for viable options to reach that goal. I have read up on the forums but a lot of information seems to be old and lots of parts have become unavailable. Luckily, my best friend is a Chevy mechanic as well as multiple other friends who are mechanics that want to help me rebuild the car, so I will have assistance. Is there any pertinent information I need to know in order to complete the swap? I believe the car had the IROC speedometer swapped into it as well.

Unfortunately the car had plenty of mice living in it so I plan to completely redo most of the interior, as well as expect to have to rewire a lot of components. It was pretty easy to find interior components such as new carpeting and headliner so I should be good on that front. I am aiming for a well handling build so I also plan to redo the suspension.

Any help would be awesome. Thank you! I will attach some pictures of the car if anybody would like to see the current state.

 

Welcome aboard George. Sounds like a fun project.

 

Thank you. Looking forward to it

 

Cool project. Do you also have the engine wiring harness from the donor Z28? It will make it easier for the swap, but if you don't have it, it's OK. The harness from the TBI motor can be modified for TPI.

Given that you say you have limited experience working on cars, but want to learn, that's excellent. This project is ambitious for one with limited experience, but certainly doable if you do your research, go slow and keep it simple. While 350whp is cool and possible, it does take a lot to get there with a TPI 350. My recommendation is to take that 350 you have, do a mild refresh on it. Pull the heads and check the cylinder walls, pop some bearing caps and take a look at those and replace bearings if needed, swap in a mild cam (like a ZZ4 cam), new valve springs and all new gaskets/seals. Put it in the car and run it. You can do high flow TPI parts, headers/etc. and those will increase hp as well, but aren't mandatory. Can also do those later after you get it up and running and bugs worked out.

Where in CT are you?

 

Very late to this thread, but as someone who started out incredibly green to cars, definitely enlist the help of a friend who’s into to old cars, especially an old GM guy. He/She will be super useful for if you get stuck on something or want a second pair of eyes double checking your work. If you don’t know anyone like that, stop by a local car club and make some friends

Good luck with the project! There’s a lot of great people here that can help you if you get stuck.

 

I unfortunately do not having the wiring harness from the donor car, just the ecm.

Luckily I will have my mechanic friends helping me out, including one who works for GM now, so at least I'll have some help when I get stuck. Will definitely be useful for rebuilding the motor and learning the ins and outs. I already planned to refresh the motor and replace the rings and replace the bearings while I already have it apart as well as all of the gaskets/seals. Where is a good place to pickup a mild cam such as the ZZ4 cam? I do agree it is a good idea to just get it running and then worry about power later, will likely take your advice on that. Definitely a good way to learn how to rebuild a motor anyways. Definitely needs a new exhaust so I plan to do something high flow with the headers and exhaust. I did see a lot of stuff that the heads themselves have issues with flow. Would you recommend switching those out while I already have it apart?

I am located in Monroe, in the Fairfield County area.

 

Thank you! Hopefully it will go smoothly but as we all know, it never does lol

 

If the cylinder walls look good, I would probably just leave the pistons and rings as is. If the bearings are showing copper, replace them, but if not, leave them be. If the motor ran good before it was pulled, chances are it doesn't need much. The heads flow OK, not great, but I don't think I would change them. You'll need to do a little work to the heads, probably have a valve job done and maybe resurface them. Change the valvesprings, retainers & keepers to accomodate the higher lift of the cam you choose. Beehive springs and +0.050 retainers are a common upgrade to handle the increased lift. Will need to check retainer to valve guide clearance to make sure you don't have an issue. There are also some good cams from Comp that will work. but the GM Performance ZZ4 cam does work well in a TPI application. You can get one from Jegs, Summit Racing, Pace Performance and a bunch of other online retailers.

Headers are good, add power and sound good, but are generally a PITA. I do have headers on mine, but for a mild build, I could really go either way. The L98 manifolds, high flow y-pipe/cat and 3" cat back is a good setup too that will bolt right in and won't have all of the issues that go along with headers.

I'm in South Windsor, so not too far from you.

 

Sounds good, thank you! The motor has been sitting for 10 or so years so hopefully I don't run into too many issues. I plan to start on the refresh within a month or so. What makes the headers a pain to do?

Oh cool, not too far at all.