darcnytemare

I dont mean to thread jack...but wth do u guys mean by #6 lower pulley...and the blower will be spinning too fast lol. Im a newb to the stock eatons. I just want to better understand them.

xxkazp3rxx

well you have 2 types of pulleys.. upper and lower... the uppers are normally measured like 2.76, 2.81, 2.93, etc. they all add a certain number of psi which adds a ton of hp/torque... lower pulleys are in 2# (lbs), 4, 6, 8, etc. it normally adds approx that many psi.. ie; 2# lower = + 2psi, 4# lower = 4psi...

The eaton is only meant to handle to much boost... most people with ported blowers which are a lot more efficient and doesn't create as much heat, run a 4# lower with a 2.81 pulley which is right around the sweet spot for the eaton. If you create to much boost... ie: 2.8 pulley and a 6# lower... you run the risk of overheating the eaton, which can cause it to fail and heat soak creating power loss.

Go check out CobraBob's site.. a lot of good info for newbie cobra owners..

http://stangshiftergaskets.com/2003_2004faqs.htm

Also check out this site for numbers..

http://www.stiegemeier.com/faq.html

Stiegemeier has ported more Cobra blowers then anyone... he knows his shat

xxkazp3rxx

and btw.. I mispoke... I meant 17psi is right around what most people want to run on a ported blower, not 14, lol.. sorry guys.

AZ SNAKE

Im running 6#lower with 3.0 upper at 16psi

darcnytemare

so on a stock eaton...its no good to run a something like 6# pulley because it creates too much boost and itll generate higher temps in the intake. BUUUUT if the blower has something like a stg.3 port u can run a more boost as it wont generate as high of temps.

O BTW...i been reading everything on that link you posted and its very helpful. I been lookingto sellmy 99 cobra and buying an 03/04 so im just doing as much research as I can on these cars.

xxkazp3rxx

you can run a 6# lower with a few different combos... look at that link that I posted for steig. he has a breakdown of what psi you would run... you want to stay close to 17#'s... but, an upper pulley will give you more peak power, while a lower pulley will give you more torque and a better hp/torque curve... I had a 2.81 in my Cobra, but if i had it i might have run a 4# and a 2.93 upper pulley to have a nice counterbalance... I mean my power curve went like this, but then again I probably had a tune by one of the best tuners for these cars...
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AZ SNAKE

According to my tuner (the best around here) My set up is optimal, runs strong. I put down 490rwp and 501tq. Stock fuel system just a KB BAP. Of course every other bolt on besides a new Blower. Whipple and Fuel System coming to the AZ streets soon. The 373s in my mind made the biggest difference.

xxkazp3rxx

Snake you have a good setup... lol... and imo, the straight axle makes a huge difference... the 3.73's aren't much of a difference... but the combo of the two makes it feel A LOT stronger.


Snake- do you have the stock differential unit in there?

Blownsvt

my 4# lower 2.93 combo only read at 14 psi, but still produced 522rwhp. the typical combos are 2# with a 2.76, 4# with a 2.93 and 6# with a 3.1.

xxkazp3rxx

Blown - your setup is a very nice setup... only usin 14psi to make that power... My cobra was about 14psi (no lower pulley)and i made just about 500.. can't remember what it finally put down, I have the graph somewhere...