PDA

View Full Version : Upgrading my 91 SC



AMD[H]unter
09-14-2006, 01:34 PM
Hey, guys. I am new to the SC "upgrading" scene, although I am fairly knowledgable about cars in general. I have a 1991 SC with over 200k on the clock, and the engine has around 90k or so. Everything works fine, except my heater core which started leaking yesterday, and is bypassed for now.

Anyway, my upgrades are as follows:
Custom 3" intake
Flowmaster mufflers, with no cat's or res's using 3 inch pipes
3.73 gears
5% underdrive pulley


I have had problems in the past with HG's, as has everyone else. I want to get my heads and bottom end "ready" for a better blower when i can afford it. My question is this; What is the best things to do in my situation? I am looking to make the heads flow better so i can run more boost, so I know I want some ported heads, but other than that, what can i do? Keep in mind, I am a highschool senior with not very much money at all.

Also, what is the leading cause of death for a SC engine other than those blasted HG's? I have been told by my uncle (who builds race engines) that high RPM's are a frequent cause because of the wieght of the pistons. Is there any place to get lighter pistons for the SC's?

kenewagner
09-14-2006, 02:01 PM
One weakness in the SC is heat. They have a marginal radiator, and The intercooler beside being small and poorly designed is mounted in a poor location for air flow. Overdriving the blower makes more heat so you have a computer pulling timing so as not to melt down your engine. Solve heat problems and your engine will love you. Better IC, a bigger radiator, 180 degree thermostat, a chip burned with a lower setting for the fan to come on. The menthol injection is another way to cool ACT temps. You find these cars run like raped apes when its winter and cold outside and drag butt when its hot. They have other problems that are solveable but heat is a big factor

Ken

AMD[H]unter
09-14-2006, 02:39 PM
Well, I use the fan mod so now it stays on all the time, so my car never gets hot; so I am covered there. I might get a double intercooler, or I might get a front mount intercooler.

JL_Bird
09-14-2006, 04:54 PM
If your in high school on a budget and your thinking about a front mount intercooler, you could check out and place that wrecks diesel equipment. Look for a suitably sized intercooler off a turbo diesel. If you have a well equiped shop class to work in you could surely modify it to fit in front of the rad. The A/C should be taken out, and I would add dual high flow electric fans. Going to a setup like that would also let you run a wider rad.

Quote:
I have been told by my uncle (who builds race engines) that high RPM's are a frequent cause because of the wieght of the pistons. Is there any place to get lighter pistons for the SC's?

If your taking the engine that far apart spend the money on a good balance job. There are lightweight pistons but they will cost you. Also make sure the rev limiter is doing it's thing.

AMD[H]unter
09-14-2006, 05:02 PM
Yeah, I have a buddy that helps me with the work on the car, so I have access to a shop. How much a good balance job cost, and would it really be worth it to keep the thing from flying apart while at high RPMs?

Thanks for the tip about the IC.

My goal is to have 300HP at the wheels when I am "finished" with it.

AMD[H]unter
09-15-2006, 10:47 AM
bump? Anyone got any more ideas? David, you seem to know what you are doing, care to lend a hand?

kenewagner
09-15-2006, 11:07 AM
unter']bump? Anyone got any more ideas? David, you seem to know what you are doing, care to lend a hand?

Think about a bigger MAF & TB to go with the 3 " intake. The Eaton blower need, as much as possible, unrestricted air on the intake side. I have the 75MM TB and a 76MM C&L maf. More than enough air flow for you & everything is easy to bolt right on. Think about a chip and tune cuz when you start changing the factory parts, a tune becomes very important. A real good Double Intercooler with a built on fan shroud that bolts right on would be what I would recommend. Send me a PM if you want a recommendation for where to get one. Cooler air temps mean you can up you overdrive another 5% as well

Ken

AMD[H]unter
09-15-2006, 01:17 PM
Thanks for the input, bud! I will look for a TB and MAFS soon. I am having other problems, though. My tranny slips in the morning when I pull it down into drive as I am leaving my driveway. It drops to nuetral, and I have to stop, and wait for it to drop back to drive.... I am not able to get a good reading on my tranny fliud, but it seems to be full. I would add some fluid to be safe, but I have heard it is bad to overfill the fluid, even by a small amount. If the fluid isn't low, I might need a tranny soon. I cant afford a new one, so I will have to buy used; has anyone got a line on a low miles tranny cheap?