Pulley sizes...

Mighty1

Full Access Member
Joined
Oct 26, 2010
Messages
316
Reaction score
0
Location
Miami, FL
My engine should be finished sometime this month and then it will be time to start working on the dedicated belt drive for the paxton. (No, not from DLM) I want to go to the next size wider belt from stock so I will need to change the supercharger pulley and of couse add an additional crank pulley. Do you guys have any suggestions as to the diameters that would be good to shoot for to get around 10lbs of boost with fully ported heads and intake? I really don't want to have to make more than crank pulley.

I know I shouldn't go real small on the SC pulley due to slippage so should that stay stock diameter? Or go larger and then try to make up the difference on the crank pulley?

Thanks for any info!!
 
I have a thread on some crank pullies being made, need to check it out, but the lower pulley is best less belt slippage
 
Yeah I saw that thread but I am going to a dedicated belt drive for the supercharger so it will have to be a double pulley or an additional pulley that will bolt up inside the stock pulley. Stock diameter for the engine accessories and then larger diameter for the supercharger.
 
Yeah I saw that thread but I am going to a dedicated belt drive for the supercharger so it will have to be a double pulley or an additional pulley that will bolt up inside the stock pulley. Stock diameter for the engine accessories and then larger diameter for the supercharger.

I've got a paxton on my 5.9L and I think the crank pulley is 9" in diameter and the charger is 2.5-3" but would have to verify that. It's also an 8rib belt. And it makes 10-12#s
 
I believe my paxton has a 2.85in pulley and with the stock crank pulley was supposed to be at around 8lbs.

Anyone know the diameter of the stock crank pulley?
 
And how much boost do you usually loose going from stock heads to fully ported heads and intake?
 
And how much boost do you usually loose going from stock heads to fully ported heads and intake?

Lots. According to FSTJACK and Ram from Hell's builds they basically lost everything. They then both changed to JMB's Procharger and now make tons of power.
 
I would love to be able to switch to the procharger setup but it's just too much $$ for right now :(
 
I would love to be able to switch to the procharger setup but it's just too much $$ for right now :(

The Paxton's are fine for good horsepower. I was there when Chubby's truck put down over 700hp to the wheels with 12lbs. That's more than enough street horsepower. I guess it would be cool to slap a procharger on and say that u put down 900hp. But really? What are u gonna do with that kind of horsepower on the street? Even at the track, for that matter? To get it to hook correctly. you're gonna need full slicks and some sort of rear suspenion work. And once you get it to hook, now u gotta worry about shit breaking. My goal, after my build, is gonna be a solid 700 to the wheels.
 
The Paxton's are fine for good horsepower. I was there when Chubby's truck put down over 700hp to the wheels with 12lbs. That's more than enough street horsepower. I guess it would be cool to slap a procharger on and say that u put down 900hp. But really? What are u gonna do with that kind of horsepower on the street? Even at the track, for that matter? To get it to hook correctly. you're gonna need full slicks and some sort of rear suspenion work. And once you get it to hook, now u gotta worry about shit breaking. My goal, after my build, is gonna be a solid 700 to the wheels.

And my goal is to spank Steve a.k.a. Sanqueen with less power and N/A ;)
 
The stock crank pulley is 6" in diameter,I'm running Stinkers 7" crank pulley with the stock 5.6# ROE pulley and its hit 11# of boost with new belt and no slipping!(Im also at 3000' elevation,so you sea level guys will get upto 2# more boost then I will get)
 
I've heard of paxton's losing boost with ported heads. But that thread pretty much was about serious belt slippage.:dontknow:
Boost is a measurement of back pressure so to speak.

So by porting heads, aftermarket blower cams and full exhaust all aid in making the engine more efficient. If you can get air in and out quicker, it will lose boost. However, doing that will be a gain in power.

So please dont think of "losing boost" with porting heads as something negative.:rock:
 
The stock crank pulley is 6" in diameter,I'm running Stinkers 7" crank pulley with the stock 5.6# ROE pulley and its hit 11# of boost with new belt and no slipping!(Im also at 3000' elevation,so you sea level guys will get upto 2# more boost then I will get)

Thanks for the info!! So I guess I should maybe go 8" on the crank pulley and then figure out the SC pulley from there. The SC pulley will be much cheaper to change then having another custom crank pulley made.
 

Latest posts

Support Us

Become A Supporting Member Today!

Click Here For Details

Back
Top