Hello all! Ok so ima bout to buy a s/c off a friend of mine and it already has the nst pulley(9.5psi).. i currently have a nst underdrive pulley.. my question is,

A)Install the s/c and keep the underdrive pulley on and get a belt that fits.
B)Install the s/c and remove the underdrive pulley.

Im jus curious if leaving it on will give me more boost? Too much boost without a tune? Or if i can even find a belt that will fit with the s/c and underdrive...

P.S.- My current mods are I/H/E, and underdrive pulley. ohh! and im a auto.. i know i know blah blah.
Anyways! any help or info will help. thanks!!

 

Underdrive pulley will give you less boost. You want to remove the underdrive pulley. If you still want the NST pulley get their lightened crank pulley but is the same diameter as the stock and you are set.

 

Yup^^^^what he said.

 

yes and give me your underdrive pulley

 

ok, another question, how will it give me less boost? why does it matter if all the size decrease is in the s/c pulley? sorry if that doesnt make sense.. lol

 

The underdrive pulley is smaller (crank). This is your drive pulley and by reducing it's size you reduce the linear speed of the belt on the crank pulley thus reducing the speed of the belt. Therefore you reduce the speed at which your supercharger pulley is spinning. Slower spinning pulley on supercharger = less boost.

If anything us supercharger guys would like a crank pulley that is an OVErdrive and then with smaller assessory pullies ^^.

 

ok that makes sense now. so its like the belt on a adjustable drill press... hmm. cool cool. so i see tuned on a unichip? ive been doing alot of reading on those things lately.. whats ur personal experience/opinion? Gains? Easialy tuned?

 

Unichip = craptastic. Very small tuner base

 

care to explain? ive heard of people getting almost 230whp on just a unichip tune on stock boost...?? im jus curious bro, not trying 2 challenge u..

 

Im sure if you have tuners near you, you can probably get it tuned and it would be great and dandy. Its just got a very small tuner base. Like here in Ga there is 1 place that tunes them. Next closest tuner is 1 state over.

 

ok just wondering since this is a topic about the s/c pulleys ive been told that 1. auto tranny cant take more then 250 hp or it will blow but i keep seeing kids on boost around 260-270 whp with auto so what is the max before i blow the tranny and 2. ive also heard u can run 3 different psi for the s/c 8psi 12 psi and 20 psi or is this false and what is the most u can get psi out of a s/c and max hp i can get with out blowing the tranny thanks and what do i really need to get the max out of a s/c

 

don't worry, there is no way the supercharger can even make enough power to blow the automatic transmission.

as for boost, you can order a 9.5 psi pulley right off the shelf from NST from somebody like dezod or garage1217. you can order custom sized pulleys like 10.5 psi or 12 psi from NST directly. then the maximum boost you can get from a smaller pulley on the supercharger is 14 psi, that is the smallest pulley that can be fitted. with the 14 psi pulley, you might make it to the limits of what the auto tranny can hold.

 

so at 14psi what am i looking at for whp isnt it around 320whp or more? if so thats far off the 250 lol i was told and thank god i didnt wanna be stuck at 250 lol and do u by chance know how much a 14psi pulley would cost me or the web site i can look at them

 

with the supercharger, highest dyno run was like 311 whp, that was a manual with 12 psi i think. the automatic tc dyno's considerably less whp than the manual.

i don't remember the pricing, but i would guess 150-200 dollars.

 

so just got off the phone with nst and for around $200 i can get the 55mm pulley and belt for 12-13psi hmmmm im in love i cant wait to get it just sucks got to wait about a month to get it

 

^ Just let me know when your ready to upgrade your bearings!

 

You're going to need a few more things if you want to run that size pulley safely = meth kit, piggy back and tune and if you want to make even more power, some cams too.

 

ok yall im kinda irritated, this is 09tC_Kidd btw. it wont let me log into my account so i made this one.. lol

anyways, so on my auto tranny whats the most i can get out of it as far as boost wise? ive been told that any more than the 9.5psi and u have to get a tune, is this true??

 

Not sure about the tranny, but yes to the second question, even at 9.5 psi you should get retuned.

 

ok, so with everything everything i have now(full header back exhaust) and the 9.5 pulley and intake what should i be looking to dyno at? roughly?