Zach06CobaltSC

I really didn't want to do this....but after watching my buddy beat a bmw m3 on here the other night....i need more power lol. I am thinking 60lbers and the smallest pulley that is SAFE to run.

I will be running meth, a cxracing heat exchanger, and POSSIBLY a dual pass endplate with option b.

If I can find someone, a shop, or gm to not rape me on install for the dual pass end plate with option b, i will grab it, if not, i will let meth make up the difference.

Is 2.6inch and 60lbers considered "safe". Obviously i will be getting a professional dyno tune for it.

EDIT: how much more power would each pulley gain me. I am currently at the stage 2 gm pulley. If I dropped to nates 2.9 pulley how much WHP would i see, if i dropped to a 2.8 how much WHP would i gain, if I dropped to a 2.7 how much WHP would i see, and if i dropped to a 2.6 how much WHP would I see.

Thanks so much for the help guys. I am just trying to see which pulley is best for my setup, because i dont want to over spin the heaton, i mean eaton, haha, and I want to stay safe and very conservative.

restonSS

2.7 is the safest, and even then ppl will argue 2.8 is the safest. the smallest pulley you can run without overspinning the supercharger is somthing like 2.731xxxx. i saw it on here not too long ago. with ur mods. go 2.7

thatotherguy

2.6 is not safe unless you want to cut the supercharger life in half or more. i ran a 2.8 on my car for 22000 miles and blew the head gasket, 2.9 would be the better one to go with unless you have the $ to change the head gasket in the future when it blows.

Super_SS

so its a m3 u wanna beat? ur not to far behind, i crush em.

but, if ur gonna go meth, HE, option B, i would port your eaton and put in a 2.7 with a good tune.

Zach06CobaltSC

I can get a very very good tune. Stock with GM Stage 2, and a custom 3 inch exhaust with no cat and magnaflow muffler. Stock header/downpipe. I laid down 245.9WHP. So I shouldn't be to far behind.

I need to beat the N/A inline 6 bmw m3. I KNOW its possible for a cobalt to do it, because i watched a 4 door cobalt sedan do it last night. WOOT YEA TIM!!!

So do most people agree that 2.7 is the safest, i know MANY MANY people that run lower then 2.9 and have never had a problem. So I know that 2.8 is also very very safe.

How much WHP would each pulley give me?

Also, this may be a dumb question, but will I be able to hear the supercharger whine more with a smaller pulley? because currently with my exhaust I can only hear it at around 5-7k.

thatotherguy

my supercharger whine is loud at 3200k rpms

Zach06CobaltSC

thats because you have a 2.5inch pulley. I don't feel comfortable, nor think its safe to run a 2.5inch pulley.

Different strokes for different folks. But I am sure you love your car bro. Hopefully she lasts a long time! Noticing all of your mods, maybe it isn't all that "unsafe".

rrutter81

I would never go smaller than 2.8 if (safe is in a sentence) you will over spin it bad enough with even THAT. If you aren't using cooling mods you will heat soak fairly bad as well.

Best bet:

Get a 2.7 pulley for racing and a 3.0 for dd. When you want to go racing just slap it on before you meet. Take it off immediately after. Even then, your risking blowing something up.

thatotherguy

to tell you the truth im waiting for the supercharger to DIEEEEEEE because then im throwing a procharger on that bitch lol

brownbandit9

i would not do the 2 different pulley idea..my tuner mentioned how bad it is to pull the pulley on the m62...its hard on the shaft and that u shouldnt do it more than a couple times.

an0malous

your tuner is an idjit.
its a 2 minute job, and doesnt put any stress on the shaft whatsoever.

also, 2.7 is not "safe"
2.8 is right on the rpm limit of our blower,

if you want it truely "safe" stick with 3 inch.

nuttzzy

you know whats the safest bet...? pullying the stock pully back on and trading that balt off for something better. to bad we cant all afford to do that.

rrutter81

^^ agreed with everything you say. However I dont see and issue with running a 2.7 for a couple of runs as long as you switch it back on. Still is a risk either way under 3.0.

Changing pulleys is easy, just use a modular pulley system, same hub.

an0malous

meh, nothing wrong with running a 2.5 if your only doing it for a few runs.

i mean more as a permanant pully.

rrutter81

definitley ballsier than i

i do not endorse this comment lol