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anyone run a 3.6 pulley? opinions?

turbotooslow

New member
Hey guys, I'm looking to mod a GTP very slightly, as it will be my daily driver. Plans so far are intake and 3" dp, and I originally wanted to do a 3.5 pulley. I am much more concerned with engine health over performance, but still would like a decent balance. I don't want to have to mess with a tuner or software unless I get into more serious modding, so my question is will a 3.6 give me any significant gain over the stock pulley? Or is it not worth the money? Thanks all!
 


Significant, not really. Their is an estimate on how much boost you gain per pulley drop, this would be dropping 2 sizes from the stock 3.8 pulley. I am not positive how much Psi it is estimated per drop but im sure someone who knows will post it.

The big problem with dropping pulley sizes is worrying about knock retard [Kr] which results form uncontrolled detonation in the combustion chamber due to heat. Optimally you want access to a scanner to scan for Kr as it would most likely be your biggest enemy.

Allot of people start with the 3.5" and you could run it with very little if any Kr [assuming the intake you get is cold air or fender wall]. If you do get Kr under $300 worth of mods would reduce it significantly. A power log [$120- 200], 104* plugs, 180* T-stat. A tune or an upgraded pcm [$100 for v1] would also provide some help battling Kr and also add some performance. Only problem with an upgraded pcm is that you would have to send out your old one to be reprogrammed [some one correct me if i'm wrong about this], and as your DD this wouldn't be much of an option.

We really need to know your goal, and how much you plan on spending to reach it.
 
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I am not positive how much Psi it is estimated per drop but im sure someone who knows will post it.

About 1 psi per 0.1 , But also depends on Exhaust back pressure yada yada yada. Im at 17 psi right now with the 2.8
 


About 1 psi per 0.1 , But also depends on Exhaust back pressure yada yada yada. Im at 17 psi right now with the 2.8

holy crap! how does your engine hold together? how are you making that much boost safely on an m90 setup?

i see all of your mods, but it just doesnt add up. your boost level should be lower. somewhere in the 14-15 range, by nowadays standards.
 
holy crap! how does your engine hold together? how are you making that much boost safely on an m90 setup?

i see all of your mods, but it just doesnt add up. your boost level should be lower. somewhere in the 14-15 range, by nowadays standards.

Ummm...Well, The mods you see is what i have. As far as safly goes...In my opinion i could definetly be safer because I havent even tuned with a wideband. I need to get one soon but have some other things that i need to take care of on the car first. I have a fullsized I/C so that may be helping the boost get in that range. But then again ever Since I put the custom pid for the boost gauge on my scanner I have had a real bad Y pipe leak ( I dont think much exhaust is comming out of the mufflers at all lol) So thats lost back pressure also. May increase a psi once i get that fixed.




Ill post up a video in the lounge tomorrow of me doing a cupple runs with my scanner in view so you can see what im talking about.



I have 110000 miles on the car. It's been good to me so far, Knock on wood.


I think it's pretty cool, usually when im idleing at the normal range (825 for me) I have zero boost. But when it fluctuates probably to about 925 I'll actually have 1 psi of boost at idle. It's just for a second but still. Thought it was pretty cool since my brothers turbo duramax has like 4psi at idle lol.



Sorry for thread jacking.
 
We really need to know your goal, and how much you plan on spending to reach it.

My goal is a DD with intake, 3" dp, U-bend delete, and possibly, at the most, a full exhaust. But that's the furthest I would take her, so I'm wondering if with a 3.6 pulley I would be set for a reliable DD with the other 'mods' stated.
 
so I'm wondering if with a 3.6 pulley I would be set for a reliable DD

Well FWIW to you my gtp is the only car that is running that i own and it is my dd.....Just depends how far you want to go...I said i want to do mid 13's and im done....now look where im at :th_depressed: But my car i consider is very realible in my opinion...but i get what your saying
 


Well FWIW to you my gtp is the only car that is running that i own and it is my dd.....Just depends how far you want to go...I said i want to do mid 13's and im done....now look where im at :th_depressed: But my car i consider is very realible in my opinion...but i get what your saying


Haha we all get a little carried away.. and that's definatly not a bad thing:rolleyes:

The thing is, I don't want to have to tune and scan my car on a daily basis because I'm not a big racer, not a track rat, probably will never go to the track. So the real concern is reliability without a tuner!
 
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