'90 SC needs TLC in performance dept.

SK_BlownThunder

Registered User
I posted a thread a while back about my SC upgrades but lost it somewhere back in February +/- a month or two.
1990 SC stock 5-speed ready for a little upgrading.
Need advice on what, where, and how much to get.
I want to start out cheap and work my way up. I have been looking at exhaust systems lately. Need something to add a "kick" without loosing much gas mileage. It is still my day-to-day summer driver but I will be racing it occasionally on the strip. To hell with the environment, my first proposed step is removing the cats. What is the status on a Flowmaster kit, should I do it or look for something better. I need some ideas. Approx how many more horses can I get from just removing the cats? (No easy access to a dyno available) As well, I need something that SOUNDS like performance.
What is the best way to set it up? I would like to go for a true dual design but without hanging the new system below the fuel tank. I'll probably have to route the new system side by side where the stock one is sitting, can this be done? As well, on the intake side, I need to know what to do. Go with a K&N panel filter in the stock air box or pull it all out and use a cone? And what exactly is the air "silencer". It sounds pretty useless from what I hear.
 
t, my first proposed step is removing the cats. What is the status on a Flowmaster kit, should I do it or look for something better. I need some ideas. Approx how many more horses can I get from just removing the cats? (No easy access to a dyno available) As well, I need something that SOUNDS like performance.

You will have a hard time finding a shop that will remove the cats for you. You can do it yourself if you don't have any emissions checks, but you will have to fabricate new downtubes. I don't think it will at all performance wise on your car and with the rest of the exhuast still being there. All it will do is make the car loud, esp. inside. I would suggest you try and find a newer style gas tank (92+) as it is easier to work with when bending exhuast. You can get by with the odler one, but if you can find a newer one, go for it. While you have it out, upgrade the fuel pump.

I would reccomend saving up the money until you can get the full exhuast done. It will be cheaper and better setup in the long run. Here is a common and proven setup for an SC:

Get a pair of high flow cats(2.5" or 2.25"), run pipe back to a dual in, single out resonator, then run a single pipe(3" or 2.5") back around the gas tank, and then a Y pipe(2.5" or 2.25") back to a pair of mufflers.

Go with a K&N panel filter in the stock air box or pull it all out and use a cone?
Niether one will really gain you too much performace. I wouldn't go with a cone unless you make or buy a heat shield to go with it.

And what exactly is the air "silencer". It sounds pretty useless from what I hear.
The air silencer is located in the fender well below the stock air box. Yes, it is pretty much worthelss, and can be removed so you can hear the intake more. Check out the FAQ's section for an article on removing it, as well as a bunch of other helpful info.

Thomas
 
Back
Top