I have an '85 GSL that is in really good shape.

The engine has 95000 miles and is, of course, a bone stock 12a.

I have been thinking about rebuilding the engine to produce a little more power and to just make the car bullet-proof if you know what I mean.

What are my options?

What can I do with a 12a for say, 3k or less. I have a great shop (Kearney Racing) near by that can do about anything I ask including going to a 13b if I wanted to. But I think I want to stick with the original 12a and do modest performance upgrades.

Street porting, exhaust header and exhaust, K/N air filter mod etc. are all no-brainers I guess, but what are my other options like intake/carbs etc.?

Any suggestions would be appreciated.

 

If you are going to go with a mild street port talk to sterling or carl about getting your carb rebuilt by them to add quite a bit of power. They also port your intake, I think...

 

Yeah, a mild 12a SP can easily be fed by an Rx7Carl/Sterling carb if you tell them that's what you need it for. You're gonig to have to get used to doing some of your own tuning on it to get the most power but you can do it.

For the engine itself, spare no expense. Get the full overhaul/rebuild kit with apex seals and springs, corner seals and springs side seals and springs, all the soft gaskets... the works . There was a thread on here a while ago giving some advice about building a strong 12a motor that you could probably use.

Remember, with a SP engine, you'll need good exhaust and a good carb. Don't forget that a good carb needs a good fuel system! I use a Mallory Comp70 fuel pump with a Holley 1-4psi Fuel Pressure Regulator and some generic fuel pressure guage.

So :
- Rebuild kit (if you do the rebuild yourself you save money and can be assured of the quality of labour... get the rebuild video from www.rotaryaviation.com)
- At least a header and cat replacement pipe, at most a full RB exhaust system (www.racingbeat.com)
- An Rx7Carl/Sterling carb (message Rx7Carl or Sterling on the forum, or visit www.sterlingmetalworks.com)
- A Fuel Pump and Fuel Pressure Regulator

and you can take the housings somewhere to be ported.

That might run a tad over 3k for all that.. but you can start with the engine and work your way out. The 12a SP won't run it's *best* with stock carb, fuel system and exhaust, but with very little tweaking it will run.

Jon