Now for a pulley

1QuikV6

Registered User
Ive got the CAI and got the Magnaflow muffs on my 90 SC auto, and now Im ready for a pulley. Not sure whether to go with a 5 or a 10 and if aluminum makes a difference over steel in a relatively stock application.

Im making 10psi right now and its just not cutting it. I got smoked by a late model Eclipse GT V6 for gods sake. I'm aiming for 15% preferrably. Would it be better to do a 5% jackshaft and 5% od or just a 10% o/d?
And if anyone has a 10% for sale, preferrably in the DC metro area, please PM me.
 
I would go with an aluminum jackshaft pulley, less weight the engine has to turn. Expect about 1.5 pounds increase for each 5%. If you have a stock exhaust beware!! More boost on a stock exhaust could be hazardeous to you engine.:eek:
 
Id really like to do a 5% jackshaft and a 10% underdrive. Ive got a new engine coming so if this one goes to hell then I have a backup lol.
 
Iwould go the other way around. A 10% jackshaft is less likley to slip than a 10% blower pulley.:D
 
What if i went with a 10% jackshaft and a 5% overdrive? that would be a total of 15% overdrive which should net me an additional 4.5psi correct?
 
1QuikV6 said:
What if i went with a 10% jackshaft and a 5% overdrive? that would be a total of 15% overdrive which should net me an additional 4.5psi correct?


that would be wayyy to much overdrive on a stock charger. you might actually run slower due to all the heat it will make from spinning it so fast. Magnaflow muffs are good but you need to get rid of the stock cats that have a 90degree bend in em before you get to much overdriving. Id only do a 5% SC OD at this point
 
stock cats that have a 90degree bend

I'd love to know why they did that anyway...

5% o/d would only net me about 2psi... oh well. Not really a point in swapping a pulley then
 
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You also didn't say anything about a better intercooler, and with that much OD you would be making some serious heat!
 
Im not planning on any new IC's or anything major. For one i cant afford it and two I have an S4 I'm trying to invest in. I just want to make it a little faster. When I feel like flying the S4 is my ride of choice but the SC shouldnt be a slouch in comparison.
 
These cars are a balance. Spin the blower make more boost. Also make more heat. If you run much over 5% then you really have to free up the exhaust. An ic fan will help a lot.5% od will give you godd proformance gains. A hot intake charge is not a good thing. The othe thing to take into account is that it take power to make power.Or to put it another way The engine takes x amount of power to turn the blower, spin the blower faster the engine takes more power to turn it. another thing to consider is that when you free uo the exhaust the blower will make less boost. This is not a bad thing. The whole idea is to move air thru the engine as cool as possible with the least restriction as possible. More volume of air is better no matter what your boost gauge reads. There are other factors involved but that pretty much sums it up. An Ar blower runs cooler at a lower rpm and moves more air.:eek: That is sort of what I am talking about.:confused:
 
So at this point I can hope for about 1.5 psi increase... whats the point then lol. And what about all of these Kenne Bell chargers on these Mustangs. Half of them arent intercooled and those pulleys look pretty small.
 
The alky is like a "liquid IC," if you are not familiar with alky...

If you aren't do some searching around for info on the snow MAF triggered kit.


But still, don't blame me for any HG issues that arise;)
 
HG issues :rolleyes: NO Not an SC? No WAY! lol :rolleyes:

Shes gettin a 10% All or nothing I guess. Ill just stop at every 7-11 wherever I go and dump ice on her lol
 
I ran a 10% pulley with high flow cats;) , magnaflow resonator, and flowmaster 40 series for about a year with no problems, but when I started the preimptive rebuild, the fire ring was deformed, and might have even been leaking under boost. But there was an unknown number fo miles on those gaskets.

I will tell you that in the Alabama summer, the car was rediculaously slower in the heat, but if I cought a cool morning or evening, it really ran stronger.

I have a double IC with fan, and alky injection and the 5%JS + 10%SC pulley and I'll let you know how it runs in a few days :D (as I'll be measuring intake temps....). Almost had her on the road Saturday, but had brake line issues:( Then I had to take the vice grips to a bleeder valve.... Anyways, keep a lookout if you want some input on alky and 15% OD.

Later!
 
I run a 5% jackshaft pulley and 5% on the blower I make about 14 lbs of boost. I have headers to true duals no cats or res. 2 small mufflers in the back.:D
 
I would go with 10%.overdrive.

It cost more but I would put an aluminum pulley on the blower
and the jackshaft.

Just by replacing the steel jackshaft pulley with an aluminum
pulley .You will gain around 10 plus hp. with stock drive ratio.
This hp gain is from the weight savings of aluminum over a
steel pulley.

Your biggest bang for the buck would be the jackshaft pulley
swap first. then the blower pulley.

Randy
 
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