Power from 7a, looking for 200 Options

[FallenHero]

Ok, I have set my power goal for my 7a at 200 hp at the wheels.

Now the question is, how?

The obvious answer from most is 'slap on a turbo.' but that's not what I want to hear.

I am going to re-build my engine soon. Here is my plan:

Re-build enging to brand ,new stock condition + a 1.8-2.0mm head gasket to lower compression a hair. Then, underdrive pully, and retard the timing a hair with adjustable cam gears for a 'rolla. Turbocharger +large FMIC and about ten pounds of boost.(maybe up to 14psi).

I have also thought about calling up jet and having the rev-limiter on my car raised up to 6500-6800. What do you guys think about that?

So, with proper tuning and electronics, what kind of power output do yall think I'd get? I have seen turbo 7a's pulling 170ish, So I have high hopes.

keep in mind I am thinking outloud here so...

Thanks for reading.

Jon

[SpedToe169]

Doggy is right. I would highly recommend the e-manage because of the ignition control it provides. Its a cheap and proven system.

Do not lower the compression!! It is a common mis-conception that this makes more power on a turbo car because you can boost higher. This is true in an all out race engine, but in a street engine driveability will suffer greatly with the lower comp ratio. DON'T DO IT!! Boost response is very important in a street engine and lowering the compression is one of the many things that will mess it up.

Do everything you can throughout the build to prevent detonation! Prepare the chambers correctly, make sure there are no hot spots anywhere in the chamber or on the piston crown. Make sure the valves are ground correctly as well as the valve seats.

Don't waste your time and money on cams. The 7a cams are actually quite good for turbo applications. You will not find any gains with aftermarket or custom cams until you reach about the 400hp mark. Focus on detonation prevention and tuning.

The bottom end is structurally strong enough to withstand 200hp. The pistons are a weak link as everyone has said but as long as you're always mindful of detonation, have the car tuned correctly, and install some failsafes incase of loss of fuel pressure or other disaster, then you'll be fine.

If you're building a motor I suggest that you use the stock crank and rods with custom aftermarket pistons (about $400). Leave the compression ration around 9-9.5, no lower. Make sure that whoever makes the piston knows its for a turbo application and has worked with turbocharged engines before. Have the rods and crank shotpeened and beam polish the rods. Have the block checked for straightness and squareness (all the bores parallel, the crank perpendictular, etc). Have EVERYTHING magnafluxed to check for cracks and stress risers. This should be good for somewhere around 275hp at the crank.

Pay special attention to flow throughout the system. Make sure that everything is portmatched, porting isn't really necessary but some cleanup around the valve seat and de-shrouding of the valve will help a lot. DON'T make the ports bigger!! Just take the rough stuff off and clean up around the valve. Make sure all your charge tubes have smooth bends and transitions. Work done to help smooth flow will help the engine out greatly. It will reduce pumping losses and allow you to run more boost without detonation.

Theres a lot more I could go on about but its been covered before. There are 2 books you absolutely MUST read if you want to do this right. Maximum Boost by Corky Bell and Forced Induction Performance Tuning by A. Graham Bell. These two books will answer almost all your questions and tell you everything you need to know to do this right. Don't be lazy!!!!! Read them!!!!