Pulleys = what boost numbers?

[GTPJOE90]

I AM UNSURE AND IM SURE ALOT OTHERS GUYS N GALS WHAT ARE THE RELATIONSHIPS FROM BOOST MADE TO THE SIZE OF THE PULLEY? THANKS :th_mischievious:

 

[blueguy]

??

Like boost levels compared to pulley size? Because there is no rule of thumb...if your car flows good it makes less boost. Or, could make 15psi on a 3.4" if you don't flow well enough.

basically...

3.8" = 5-7psi
3.5" = 8-9psi
3.4" = 10-ish psi
3.2" = 11psi + and so on...for the most part.

 

[TheOtherNick]

^ thats pretty much it. I see 10.2 right before I shift with my 3.4
with my 3.5 I saw about 9.4 max.

 

[blueguy]

heh...I saw 15psi with my 3.2"...and it didn't knock at all...and that setup ran like a raped ape. I loved it.

 

[TheOtherNick]

Think what your new set up will be .......

 

[00gpgtp]

i see about 10.5 with a 3.3. fs intercooler, plog, stock rear mani, 3" dp....

doesnt flow the best lol

 

[BoostJunki3]

i see 12 on my 3.4 with headers

 

[blueguy]

i see 12 on my 3.4 with headers

Then it isn't flowing good enough.

I saw 11 with a 3.25" with headers.

 

[Bio248]

there is no set amount. it depends on how well your motor flows.

/thread

 

[Zach3800]

i only see 9.8 psi on a 3.4 with a huge cam and high compression

 

[blowfishRus6]

weather effects it also does it not??

 

[TheOtherNick]

yup cold air is denser and then you make more boost.

 

[Liquifire]

i only see 9.8 psi on a 3.4 with a huge cam and high compression

And I saw a max of 9.0 with my stock 3.8 setup....obviously it is all about flow....headers, porting, exhaust mods, etc.

 

[Zach3800]

flow has everything to do with boost levels so does weather

 

[SDGTP99]

flow has everything to do with boost levels so does weather

I agree! on a3.4 pulley im seeing 7psi with my port headers & catless exhaust.

 

[BoostJunki3]

Then it isn't flowing good enough.

I saw 11 with a 3.25" with headers.

im seeing 12 because im boost stacking i believe tho because i get a constant 9-10 then right before the shift it shoots to 12 real quick...

 

[blueguy]

How are you stacking with headers?

You need a ported blower...and a better tune prolly...

 

[blowfishRus6]

in the video he posted, it dident jump up till right at redline. maybe the supercharger just turning harder, idk

 

[FoSHO99]

Its a roots blower, It's pushed air. Your not going to have the same psi from car to car, pulley to pulley.

 

[Xhondaguy]

i hit 10 with a stock pulley and minor mods