Hello, new to the forum, not new to cars, fabrication or tuning OBDI & OBDII ECUS. Started as a DSMer. Still have the 90 Eagle TSI. But a long time friend of mine has a (I think 97, maybe 95) Firebird Formula he wrecked back in like 07 he will sell me for a grand. I'm thinking about buying it to swap the whole drive train into a late 80s RX7 (FC). I'm curious what kind of potential the LT1 has without going crazy.

I'm a TIG welder so I can fab brackets, mounts, exhaust etc. Curious what I could expect from the engine with a fresh hone, new rings bearings etc. With a mild cam upgrade, full exhaust from headers back which would probably have to be a custom job. Maybe new intake manifold if it's worth it? And some gasket matched hand porting and smoothing out of the cast surfaces.

Maybe it would be easier to ask what needs to be do everything to get around 400rwhp? Also imake aware the LT1 has a iron block, but unsure if the heads are aluminum?

Just trying to decide if I want to do this or not. It would be a pure toy, but street car, not focused on drag but generally just hauling ***. Oh yeah, I'm 32, been messing with DSMs since I was 16.

 

A good heads and cam setup with a well sought out tune should get you to 400rwhp N/A.. And all F bodies and Y bodies (Corvettes) came with aluminum heads.. B bodies came with iron heads..

 

That's good to hear, I'll be on a budget so I'll probably try to work the stock heads over myself.

 

No gain on using a aftermarket intake manifold for LT1. Just port match the stock aluminum one to the ported heads. You mention you will port the heads yourself, ok. Or send them to lloyd elliot and get one of his custom cams. He is regarded as about the best for LT1 H/C packages. You will need to bump up to 30 lb injecotrs for a combo getting 400 RWHP along with a PCM tune. May also need a 255 LPH fuel pump

95-97 F-bodys have been donor cars for many drive train transplants in various cars

 

I know their ECU is OBDII, are they flashable via laptop with some software or?

 

Of course.. My tuner used a program called Tuner Cats on my 96'

 

Awesome, knowing this going forward I'm feeling a lot better about buying the Firebird for the swap. Only question I have left really is how much can the stock rear end handle? I doubt the RX7 rear can take the torque the LT1 can put out, even stock for too long.

 

The stock motor with bolt -ons @ 300+hp should be enough for a 2700 lb car. Although 350hp would be a lot more fun. http://www.grannysspeedshop.com/

 

The F-body 7.5 rear end is fragile, at best, when you start building the motor. I suspect the RX7 rear end will not hold up long to v8 power.....maybe longer if it is a automatic swap but clutch dumps will take its toll if the donor car is a T56

 

Donor is a T56

Soo what would anyone suggest for a IRS rear that could handle the output reliably?

 

LT1/T56 in a RX7 will be one fun ride. IDK anything about the RX7 or how much power its rear end can handle....but I suspect you will find out. Drive it untl it breaks, if it does

With some fabrication something can be made to fit and hold up

I cut down a Ford 9" for a 57 Healy I put a 327 and Muncie 4 speed in many years ago....

 

Well I know I want to keep the rear IRS. A solid rear isn't a option in interested in.

 

If you want IRS look for a GTO or late model Camaro diff...

 

Wow they sell some nice stuff to make those swaps so much easier I see..