smaller pulley on 03 cobra

[lessurluck]

i was looking at the ford racing website and they have a pulley that they say will give you 4-5 psi on the stock sc. and i also found another one that claims a 7 psi increase so i think that would be like 15 psi after the tunning. i went here http://www.edmunds.com/insideline/do...cleId=104572#8
and the article talks about an upgraded sc pushing 14 psi... but why would they upgrade the whole thing instead of just putting a smaller pulley?
2.75 pulley and smaller belt to fit- under $200
new sc kit=$3500
so i know there must be a reason for upgrading cuz its to good to be true to save that much money for the same power. i found that 7 psi pulley on http://www.rpmoutlet.com/03cobraqu.htm. does any of this make sense or did i hit the jack pot lol

[b3warnick]

I do know that a lot of guys have changed pulleys to make some HP...but a lot have just forgone the factory Eaton SC in favor of a Whipple or KB...then the HP numbers go crazy and the stock block and internals take such mods very well.

At either case, I wouldn't by anything from RPM Outlet...lots of guys at Mach1registry have had problems with orders not filled, shitty service, parts missing from orders, etc. They don't seem to be very reliable at all.

[lessurluck]

thanks for the advice.

[6speed]

www.billetflow.com

[BlackGT2000]

The PSI is really only part of the equation. One supercharger at a given PSI could deliver very different power compared to another at the same PSI, same goes for turbos.

[lessurluck]

why is that? i can see that on a supercharger only because an upgraded sc might use less power to produce the same psi but on a turbo the only thing i can think of is that if one turbo got hotter than the other and less air molecules were able to be compressed into the given pressure... if you were thinking about something different then please help i go on these forums to learn all that i can


besides all of that my question was geared more to if the stock supercharger can handle 14 psi and will those smaller pulleys really give you a 6-7 psi increase? if it does then i think it would be stupid to spend 3k on an aftermarket sc unless your looking to really get up there into the 20 psi range

[BlackGT2000]

I will start off by saying the outlet temp is going to be higher on the eaton than on the whipple........ there is a whole lot written on this subject, most likely in older posts if you are really interested. Other wise do a quick google search it will bring up more information than you will ever read.