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Will a 3.3" pully blow a lightly moded 3800?

ncccgolf5

New member
I have a 04 GTP with a 3" downpipe and power log with new spark plugs, 180* tstat and a cold ait intake. Will slapping a 3.3" pully blow the engine? and how much horsepower will it add? What size should i use? and how much horse will I get? Thanks guys I know thats a lot. looking forward to you replys
 


Maybe.

It's a bit too small of a pulley for the mods you mention and most likely it will only lead to knock, reduced timing and either blown motor or less power than a larger pulley.

Pulley envy is evil. Don't let yourself be pulled into the smallest is best idea.
 
Will slapping a 3.3" pully blow the engine?

It won't if your knock sensors work well enough to save the engine from owner stupidity. :th_jester:

You've got a Gen V, so that is about a 3.2 pulley in Gen III terms. I haven't really seen anyone safely run that size without a cam or intercooler. I'd suggest a 3.6 or at most a 3.5 with your mods. Don't go crazy on the pulley size. Rockers would be a nice upgrade for you and might let you run one size smaller. Get yourself a modular hub if haven't already and use common sense when playing with pulley size.

There isn't much point in trying to crunch ricer math as to how much more power you could make. Too many variables. If you put a 3.3 on you might make a bit more power under the curve but top end will be joke once the PCM pulls timing like mad to stave off knock.
 
custom tune is the best. i made the noob mistake and slapped a 3.4 pulley on my gen II and it eventually blew up. i had no tune and i could tell it was pullin timing. after about 6 months (many short trips) i threw a rod right through the block. dont just drop pulley size. do some alot of research and get supporting mods before slapping a smaller pulley on it. dont make the mistake i did.
 


Get a modular setup and put a 3.6 on. You'll be pretty safe that way, and still be able to feel the power difference.
 
even with that 3.6, ull still get some knock. yes its "safer". but you still need a tune. put the 3.6 on and get it tuned ASAP!!!
 
Knock sensors sense knock after it's happened. Tune for the best timing with no knock.

Um yes, I think we know how knock sensors function. :D I was just joking, hence the smiley. :p

Back in the day people were running 3.25 pullies with a downpipe and PCM. Some people manage to get away with a lot of knock retard without engine damage as the PCM is fairly aggressive in stock form. I sure wouldn't chance it though. Stock engines almost always have some KR stock and survive just fine for 200K miles or more so the system is far from worthless. However the potential for damage is likely to increase from knock over stock though when you increase boost. Again use common sense.
 
knock on the stock pulley is much different than knock on a 3.25 pulley. the more boost you make, the less knock you want because if you have the same amount of knock with higher boost levels youre bound to annihilate your motor.
 


if yoiu dumb enough to throw it on with what little you have done then you deserve what happens next.

I have a question, why put a such a small pulley on? Its just gonna make your car slower and hard on the motor. Maybe you just want a slow car, I donno. Unless you plan on running race gas daily you will loose several tenths in thee 1/4 mile.
 
Ey guys thanks alot. I think I'm just going to go with a 3.5 and continue moding in the spring. It gotta little crazy at the end there with the "if your stupid enuf" and the "watch the fireworks" but thanks
 


Ey guys thanks alot. I think I'm just going to go with a 3.5 and continue moding in the spring. It gotta little crazy at the end there with the "if your stupid enuf" and the "watch the fireworks" but thanks

Well let me put it this way...would you rather have chunks of missing piston pieces or a running car?

You tell me.
 
Ey guys thanks alot. I think I'm just going to go with a 3.5 and continue moding in the spring. It gotta little crazy at the end there with the "if your stupid enuf" and the "watch the fireworks" but thanks


Just trying to save you a little time and money dude, you should be thanking us... Your Welcome BTW.

Some people just don't get it unless you tell them exactly what will happen or tell them there an idiot. Can't tell ya how many people over the years I've seen not listen to advice posted nicely, do the wrong thing, blow there **** up, and come back and ***** about it. I'd rather tell you your an idiot, you hate me, but you motor is fine because you actully wake up and listen VS. You don't listen to me because i'm nice, or follow the writups out there, blow your **** up, and blame GM for it because you made a dumb move. Thats how I see it anyway.

Someday you might realize, we are just trying to help and be on your side too...
 
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