I want to know who is seriously interested in an oversized crank pulley for the GM 2.4 SC. RaceTech wants $225 (US) for 1 pulley. If I can sell 5 of them he will sell them for $200 each. I think 5 is pushing it, but if we get more I will pursue a lower price

I know I have 4 people ( including myself ) interested.








Jason
99 Z24
157hp/171tq
wheres my boost??

would an oversized crank pulley be counter productive? you're increasing the drag on the engine, but increasing the boost..... hmm...


supercharged 2.4L alero
www.cardomain.com/ride/2168613

Learn more.

it's lighter (GOOD) and over drives the blower (good)

the only thing about a biger crank pulley that could be bad would be if it where heaver.
but this is not the case here.


Chris


'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08

Well, there is the argument that there is a greater opposable torque due to the belt being further from the center of rotation, but with an aluminum pulley, it wouldn't do much at all...and if you underdrive the accessories (larger pulleys for the AC & Alternator) at the same rate as the crank pulley is overdriven, then they should be fine.

On a side note though, I thought there have been people with mildly built motors, and haven't even seen more boost when even going from a 2.7" pulley to a 2.5" pulley on the m45...so to me, this seems utterly pointless anyways...any thoughts?


-

"Youth in Asia"...I don't see anything wrong with that.

learn more? come on now.... isn't that what this forum is all about?
i have understanding of the belt drive system of my car, i was just wondering the trade off of stock size to an overdrive pulley. i understand that it would be lighter, but spinning your accessories at a higher rate would be counter productive. and if you would have to change all of the pullies because of this, than it wouldn't be very cost effective.
also, from most of the posts i've seen the reason behind not gaining any more boost from the smaller pullies is because of belt slip on the smaller surface are of the smaller pulley.


supercharged 2.4L alero
www.cardomain.com/ride/2168613

In my talks with Racetech, their pulley is a hair over 6.9" in diameter which is roughly a 10% overdrive. I have measured several under-drive pulleys from different companies and they are all roughly 10% under-drive. ( and all lighter than stock ) Since many people here have run under-drive pulleys from different manufactures without issue, I really doubt there will be an issue with over-driving them by the same percentage

The other benefit is you don't have to go as small of a SC pulley as most here do. This will save you the cost and time in machining the snout down to properly use the 2.5" pulley

Also with going to a larger crank pulley will reduce and maybe totally eliminate belt slippage




Jason
99 Z24
157hp/171tq
wheres my boost??

CORRECT.

ALSO, i have used the 2.5 " pulley with, get this!!!, NO belt slipage.
the reasion for not seeing more boost (pressher) with a built motor is that if can take more CFM.

IM also geting this

Chris


'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08

Taetsch Z24 wrote:CORRECT.

ALSO, i have used the 2.5 " pulley with, get this!!!, NO belt slipage.
the reasion for not seeing more boost (pressher) with a built motor is that if can take more CFM.

IM also geting this

Chris

(Oh the immature thoughts governing my mind)...anyways...

I am well aware why with a built motor, you will see less boost at the same RPM compared to a stock motor... but I was under the impression that these people with built motors were going from a larger pulley to a smaller pulley. With the charger spinning faster for every RPM, you should see at least a little increase in boost pressure over a larger pulley...Belt slippage seems to be the only concept mentioned so far that could justify why they haven't.


-

"Youth in Asia"...I don't see anything wrong with that.

there geting a smaller CHARGER pulley,
geting a larger CRANK pulley does the same thing.

Chris


'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08

SO when do i send Money?

i want!

Chris


'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08

I still need to sell 1 more pulley for us to get the price. I am anxious to buy it myself




Jason
99 Z24
157hp/171tq
wheres my boost??

Sounds like a waste of money to me. A pulley boys setup is only $165.00

And as far as I can see it would cause more drag due to spinning the other accessories faster. The point of an underdrive pulley is not just to shed weight it is to UNDERDRIVE the acessories.


FORGET GIRLS GONE WILD WE HAVE GOVERNMENT SPENDING GONE WILD!

I'm sorry, but your an idiot.

Gain vs. Loss....... Dyno a UnderDrive pulley once. How much HP do you think your going to get? Now Dyno an increas of 3-4 psi.... at an average rate of 7-8hp per lb..... you tell me what is going to gain you more HP. Boost > Bolt Ons

In hot conditions, a 5 rib belt on a small pulley will slip...... with the larger crank pulley, you dont have that problem.




SPD RCR Z - '02 Z24 420whp
SLO GOAT - '04 GTO 305whp
W41 BOI - '78 Buick Opel Isuzu W41 Swap

Hey Jason....

I dont know if you remember but I emailed you a while back about the time when I was Racetech and Joe told me that you were trying to set this up

anyways, am i included in the list???.....i'm still interested in this

Yes, are are included on the list. I still need 1 more person

1. Jason
2. Taetsch Z24
3. 97trd(???™)
4. FlipSpeed




Jason
99 Z24
157hp/171tq
wheres my boost??

Joe is a great guy down @ Racetech !.



My Cav
I give up...
i'm buying a VW those people love trees, so they should love eachother too... "Andy"

Flipspeed,

If you are still interested, please let me know ASAP so I can get some things setup




Jason
99 Z24
157hp/171tq
wheres my boost??

if i was keeping my s/c i would be all over this like a fat kid on a cupcake

Jason....

Emailed you. Sorry for the late reply.

what is race tech website?

<a href = 'http://ivpnewmedia.com/10thst/tifts/'>
<img src = 'http://ivpnewmedia.com/10thst/tifts/dpBanner.gif'></a>

You won't find info on this on their website. I think it gets updated once a decade




14.330 @ 96.37mph

well I want to know what is there website.

<a href = 'http://ivpnewmedia.com/10thst/tifts/'>
<img src = 'http://ivpnewmedia.com/10thst/tifts/dpBanner.gif'></a>

www.racetechauto.com

Quote:

You won't find info on this on their website. I think it gets updated once a decade

Definitely won't find this part on there. This is something that I heard that he made and had to find his website just to email if he could make more




Jason
99 Z24
157hp/171tq
wheres my boost??

The racetech crank pulley is awesome ... loving mine already. I was going to go in with this group, but I needed mine ASAP so I could get it tuned with my new charger pulley, and water/meth kit.

Is anyone else interested in this??? I do have one more pulley available.




Jason
99 Z24
157hp/171tq
wheres my boost??