Interest in JBP Oversized Crank pulley..... - Boost Forum
Forum Post / Reply
You must log in before you can post or reply to messages.
Alright Fellaz, i wrote an email to JBP and asked if it were possible for them to make an oversized crank pulley for our supercharged LD9 in the idea to make more boost. I told them about how a couple of you have gotten them before, but were WAY over priced, so they said they would love to help the .org out and produce these pulleys at a descent price....i haven't gotten to the price with them yet, but i was wondering if any of you were interested or not....they said they will need 15 units to be sold in order to make this possible. Is there anyone that is intersted if the price is right?
NEW SIG COMING SOON FOR 07'!!!
would possiably been,but s/c goes bye bye soon.
good luck with it.
I am working on the same thing with a different company
Jason
99 Z24
Racers Edge
Johnny Mack Turbo Systems
Engineered Performance
I may be interested
2010 Subaru Impreza WRX Limited
1999 Cavalier Z24 Supercharged
1999 Grand AM SE (Beater Car)
1997 GMC Sierra
2007 Honda CBR 600RR
2005 Honda TRX450R
There is no real need for it, since pulley boys has the 2.6 incher for 69$, and the GM SC is USELESS past that, it only can make 6-7 PSI, find me a boost guage that says past that and I would believe it. Everyone says "10-12 psi" but it is BS, this blower maxes out at 6-7 with alky and with the 2.6. I dont think there is a need to make an oversized due to huge limitations of the M45.
http://members.cardomain.com/vertz24 1998 Z24 Convertible
Chris is right. But there's another reason why it's useless. The stock SC pulley is 2.8". You guys go down to 2.7 and 2.6". That's only 0.1 - 0.2". The pulley is already twise smaller than the crank pulley so you're telling me you are ready to pay 100+ for a crank pulley 0.05" bigger? BS.
Gilles
2.3 Ho
some of you keep forgetting the smaller the s/c pulley the easier it is for the belt to slip
the more belt contact with the pulley the less chance of slippage
so a larger crank pulley , will allow a larger s/c , and keep slipage to a minimum
crank pulley dia.
S/C pulley dia.
X
RPM = S/C RPM
6.455
2.8
=2.305
X
6200 = 14291
You'd have to make a Crank pulley 6.955 (vs.6.455 stock) to make a 2.8 pulley run the same speed as a stock size crank pulley with a 2.6 s/c pulley.
That's going to overdrive the A/C and Alt. also...
"The FACTS are always subject to CHANGE once the TRUTH is applied"
"In the entire history of man the only stupid questions are the ones that don't get asked"
well the alt regulates it self , so the rpm wont be a big deal , plus there is larger alt pullies out there
and the a/c shuts off at high rpm and free-wheels so that shouldnt be a problem
a/c will work a little better at slower speeds
so there isnt really a negitive with a larger crank pulley , unless you go to big
i thought the 2.4 crank was a little bigger than that ?? i know the eco is closer to 7"
Edited 1 time(s). Last edited Wednesday, August 02, 2006 10:17 AM
It's actually a little smaller... I just measured the 2 that I have and they check 6.420-6.425 across the top of the ridges.
"The FACTS are always subject to CHANGE once the TRUTH is applied"
"In the entire history of man the only stupid questions are the ones that don't get asked"
Another benefit is by the weight difference between the 2
I wanted to over drive the crank so I wouldn't have to use such a small snout pulley. You have to machine the snout so it will accept a pulley smaller than 2.5
Quote:
You'd have to make a Crank pulley 6.955 (vs.6.455 stock) to make a 2.8 pulley run the same speed as a stock size crank pulley with a 2.6 s/c pulley.
Yes, that is about what I am think the size should be. That is about 10% overdrive
About how 2.4 GM SC kits are out there??
Jason
99 Z24
Racers Edge
Johnny Mack Turbo Systems
Engineered Performance
hmm well that sucks then
larger pullies for everyone , lol
Well, it's been 2 days so far and no word from JPB, it usually takes them about 4 days to return there messages. The reason i think an oversize crank would be nice is because of the fact that i have an underdrive pulley, and i want to boost about 6-8 lbs. so instead of buying a stock sized pulley and also a S/C pulley all i'd have to do is buy a over sized crank and be done with it. Right? The stock pulleys (crank and S/C alike) make 4-6 lbs of boost right? So if there is an oversized crank in the stock place wouldn't that e close to 7-8? If so i'm all for it. I'll let you know when i hear something from them....
NEW SIG COMING SOON FOR 07'!!!
racetech has one for about 225$ ish. half inch bigger then stock and gained 2psi.
they said they used the stock belt too. that thing is tough to get on there with the stock pulleys.
good luck.
id like to see a 7 or 7 1/8 for a crank pulley size
although i might need closer to 7 1/2" if my race car set up comes together like im planing
I just received another email from JBP, they said the price will determine in what kind of materials are used, so i told him we'd like aluminum pulleys, and i'm guessing everyone would like a 7 1/2 " pulley right? I told them the price of racetech's pulley and told them that 225ish is crazy money for only 2 lbs. of boost, so if they could to help us in that field as well, more than anything. I'll keep you updated....
NEW SIG COMING SOON FOR 07'!!!
why would u overdrive your accessories when u can simply change the s/c pulley.
i mean all your doing is getting more resistance from all the asscessories by spinning them faster. when u can just spin the charger faster with a pulley from pulley boys.
u are bettter off getting an rsm lighten ppulley of stock size..... lose some parisitic drain
Sorry...
You have been banned from posting on this site as of 2005-09-21
00:33:32. This ban will expire 2005-09-28 00:33:32 Pacific Time.
Reason: Comments over the top regarding Jordan Kruger and other members in Versus. Also, if you have a problem with a member e-mailing you, do not bring it into the forums.
If you believe this to be in error, please contact us.
[quote=97cavie24ls(JDM&00s/c sedans™)]well the alt regulates it self , so the rpm wont be a big deal , plus there is larger alt pullies out there
and the a/c shuts off at high rpm and free-wheels so that shouldnt be a problem
a/c will work a little better at slower speeds
so there isnt really a negitive with a larger crank pulley , unless you go to big
i thought the 2.4 crank was a little bigger than that ?? i know the eco is closer to 7"
sinrocker wrote:why would u overdrive your accessories when u can simply change the s/c pulley.
i mean all your doing is getting more resistance from all the asscessories by spinning them faster. when u can just spin the charger faster with a pulley from pulley boys.
u are bettter off getting an rsm lighten ppulley of stock size..... lose some parisitic drain
as ive said alot of times before , learn to read the whole topic
Any updates???
I stopped working on the oversized crank pulley. The company I was working with wanted to do a slip over design because of the balancer on the stock pulley. Second reason is I won't be able to sell many of them if people are going to have oversized 1pc pulleys made for a little bit more money
Jason
99 Z24
Racers Edge
Johnny Mack Turbo Systems
Engineered Performance
Well, JBP said they couldn't get the price too far down...they said it'd be around 210ish$ So, i kinda said the hell with that....Pulley boys here i come...you know? If all of you still want to do it, then the hell with it, i'll do it also, but it's kinda pricey.....it's up to everyone else....
NEW SIG COMING SOON FOR 07'!!!
Maybe we should discuss a group purchase from Racetech for theirs?? I would thing they would come off the price if we buy 10 of them
Jason
99 Z24
Racers Edge
Johnny Mack Turbo Systems
Engineered Performance
I was searching ebay and came upon this, i don't know how many they have, but i ordered one. It says that it's slightly larger than stock size.....check it out!http://cgi.ebay.com/ebaymotors/XTUNE-95-02-CAVALIER-SUNFIRE-2-4L-LIGHT-WEIGHT-PULLEY_W0QQcmdZViewItemQQcategoryZ38656QQihZ016QQitemZ260018367967
NEW SIG COMING SOON FOR 07'!!!
damnit! Just copy and paste the first one....i have a mission to get ready for.....Goodluck!
NEW SIG COMING SOON FOR 07'!!!
Say, I were to use an Unorthodix underdrive pulley with the charger. How much larger than stock would the Alt pulley need to be to bring it back to stock speed???
Jason
99 Z24
Racers Edge
Johnny Mack Turbo Systems
Engineered Performance
Forum Post / Reply
You must log in before you can post or reply to messages.
