what is the best way to increase horses and torq?

2fast4you

Registered User
I need to know the best ways to increase horses and torq, without nos, and as cheap as possible, i'm thinking about playing around with the pulleys, maby a smaller one on the super charger to spin it faster and add more boost, but i need help, where can i get them, and what should i use?
anyother suggestions to increase speed?
it's for my 90 sc (auto)
 
Cheapest mods that yield the best results. (other than NOS)

#1 Underdrive Pulleys

#2 Overdrive Pulley

#3 Cheap exhaust

(in any order)
 
If your current exhaust is stock and you've any interest in your headgaskets, I would get either a cheap exhaust upgrade or underdrive accessory pullies. I believe the exhaust would yield a large horsepower increase. Exhuast upgrades have a higher effect on these vehicles due to the increased air flow through the system from the supercharger.

Adding an overdrive pulley to a supercharger with stock exhaust will greatly increase pressure on your headgaskets. I also don't know if it adds very much by itself.
 
I'm kida interested in this aswell, mine is basically stock but it has high km's (200) head gaskets were done at 160k but exhuast should come first b4 trying any pulleys. correct?

anyone find any difference in uses a cold air intake?
 
I believe the overdrive pulley is for the supercharger. It makes the superchargers spin a bit faster in order to produce more boost. The underdrive pulleys are for the accesories on the motor. I am not sure, but I think they are for the water pump and the alternator. It slows down the turning speed of those items, reducing the drag on the motor.
 
5% pulley, replace, at least, the stock resonator. cut it out and put in a Y pipe or put a new resonator in there with a properly open outlet.

10% pulley, replace the resonator and the converters to remove the 90 degree outlet angle on the driver's side cat.

That should protect your head gaskets as much as exhaust can. After that I feel exhaust mods stop impacting head gasket life and just impact engine performance.

Overdrive pullies turn the SC faster. This increases max boost, but also increases the drag placed on the engine.

Underdrive pullies increase the mechanical advantage for the crankshaft making it easier to turn the accessories, but as a result they are turned slower. They are also typically aluminum and dramatically lighter, which decreases the load on the engine as well.

My feeling is that even a 100% stock car should have the resonator replaced. It's a head gasket accident just waiting to happen.
 
While I have not changed my exhaust, yet, I was talking with someone at Carlisle last year, and he said that there are sections on the stock exhaust system that actually narrow down to around 1" in Dia., severely restricting exhaust.
So, a new exhaust is definitely the first thing you should do.
 
I've had my 90 forever and never done any upgrades for fear of blowings the head gaskets. Plus, I am no mechanic. Everywhere I go to get exhaust work on my 90, the shops don't want to mess with it because everything is so tight under there. Plus the way the gas tank is set up close to the exhaust. Any thoughts? Especially around Jersey/Pa? Im in New Caslte, Delaware.
Maurice.
 
I think it is more important what the budget allows to determine the order. The underdrive pulleys don't REQUIRE exhaust, but exhaust is always nice.

UD pulleys are $160, OD pulleys are $100, but even cheap exhaust is about $400.

IMO.:)
 
1) On 89-93 The resonator is the worst restrictor. Either have a custom Y-Pipe Made or put in a proper sized resonator. A Y-pipe will cost about $75 and a resonator around $100. The stock mufflers aren't too bad but you can do whatever you want with the rear mufflers depending on the sound that you want. I have Magnaflows on both of my SCs with no resonators and they sound really good. My 90 seemed to react a little better to the exhaust than my 95 when it came to reducing boost when I opened it up a bit. The 90 has two cats and the 95 has three. Also the 95 is a little quieter with the same mufflers because of the third cat.

2) SC Pulley either a 5% or 10%. I have a 10%+ from Racer Walsh on my 90 and it really picked up the performance. I have been running it like that for a long time with no problems at all.

3) Larger MAF - Either a 70mm from a newer SC or a 73mm from C&L. The stock size MAF is 55mm and the stock TB is 60mm. If on a budget find a 70mm MAF or about $110 for a C&L. Either way a good upgrade.

I personally don't like under drive pulleys because I have stereo equipment and these cars tend to run hot anyway. Slowing down those accessories doesn't help me. But they do work as advertised so if you are looking for cheap HP they are good for that.

You can do 1-3 for under $400 and your car will be noticeably quicker "Seat of the Pants".

Just my .02 Bob
 
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By amount of power increase...

1.) Port the heads (20 hp with minor work, 30-60 hp when combined with other mods and ported extensively)

2.) Exhaust (10 hp with new cats and res, 20+ hp with ported manifolds and all.)

3.) 94-95 blower with 89-93 pulley (15 hp if it's a wasted 94-95 unit. 20 hp if good exhaust is there and early pulley is used. The early pulley is about a 5% OD on the later model blowers.)

Of course these all cost quite a bit of $$$, but they're the best mods for power. The stock heads blow goats big time. Imagine the blower/intake side being a fire hose, the exhaust ports in the heads being a coffee stirrer and the exhaust system itself being a drinking straw. You could replace the exhaust with another fire hose, but only so much 'stuff' will go through that coffee stirrer.

Good luck,
Steve
 
WHAT to do????

what I,ve done, is made a y pipe, removed the mufflers replaced cats with larger ones, nice idle but growls at highway speeds,...........added 3/4 top, 73 maf and removed air box , 10 in cone filter K&N 8 in I/C fan, have stang headers and dobble thick I/C plus ported cast headers.........AND A 10% PULLEY WHICH I WILL INSTALL AFTER I MAKE MY MIND UP ON WHICH HEADERS TO USE.........FAST FREDDIE;) ;) :rolleyes: :rolleyes:
 
hey man, here r some websited to go to.


supercoupeperformance.com for mild stuff

magnumpowers.com for the bigg stuff:D :D :D

dave
 
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