I picked up an '89 RS with a 2.8L. It has a blown head gasket so I'm swapping it to an LT4.

I know I'll need a new harness and ECU. Plan is to get a Painless harness and an aftermarket ECU for a 97 SS Camaro that had the LT4 in it original.

I plan to use the original Borg-Warner T5 with a standard LT4 OE clutch set.

Any advice or known problems with this swap?

 

That t-5 will break within 20 minutes of use. They can't handle much over 250 ft/lbs.

 

my buddy has a crate 350 rated at 400 and his trans has held up for 2 years now. And hes not easy on it he went through 2 rearends

 

Those T-5's are terrible, thats why they didn't match them with the 350 TPI's.

 

Yes, also you need to make sure that the LT4 is OBD II as the crank sensor was different. You'll also need new motor mounts, and a new K-member from a V8 not suure what else, go to thirdgen.org and look in the engine swap section thats all the info youll need. Be sure to get some books too.

 

the LT4 clutch won't work

just get a good aftermarket clutch for the thirdgen

 

third gen kmembers are the same v6/v8, but the mounts are different

 

All LT4s are OBD2.

 

Do you already have the motor? If not consider getting an Lt1 and getting a head and cam package from Lloyd Elliott. I'm running an le2 and making great power. I have yet to dyno since the new cam but am confident it's over 400whp.
You can also spice the stock wiring harness with diagrams from thirdgen.org. I would go with an obd1 computer. Tuning software is alot cheaper. Another alternative would be to run a megasquirt and build your own harness. This would be the cheapest, but it would be alot of work.
This is a great project The only thing that would worry me would be the t5. If you are doing any drag racing it may not live to long. If you do mostly street driving without sticky tires you might be ok.
I hope this helps.
Kory

 

I don't think the stock Borg Warner Trash-5 transmission with hold up for very long, but you might get lucky. If you take your chances have a backup plan in case it fails. It's been a while since I've looked up anything on those, but I seem to remember a few places that have some stronger upgrade parts for T-5s.

If you don't have the parts yet, LT4 intake manifolds are getting very expensive due to the fact they aren't in production anymore. Someone on here mentioned that edelbrock will be coming out with an LT4 manifold within a few months but I haven't heard anything else confirming this. If it were me I'd weigh out my options with just putting a carb on it vs. fuel injection.

If you are wanting to make some good power having the stock LT1 heads ported and getting a matched cam for them from one of the vendors on the board is the way to go. Otherwise if you're just wanting a motor that will make decent power, idle as stock and be a neat swap into a thirdgen the LT4 would fit your needs (keep in mind if you buy the LT4 conversion kit it comes with the LT4 HOTcam, not the factory LT4 cam- the HOTcam will have a noticeable lope to it).

 

Doesn't look like anyone mentioned it so I will.. go to www.thirdgen.org and look under the Engine Swap board, lots of folks have done the swap and there is more thirdgen specific swap info there.. as for the t5, the above folks are correct, try and get a engine and tranny together..