So im looking into getting under drive pullies for my 96 gt and i came across these:

http://cgi.ebay.com/ebaymotors/1996-...ht_2344wt_1165

So i was wondering if they are an investment thats worth it

thanks!

 

No if it were me I wouldn't. Steeda udp only

 

I agree with Harbre. If you're going to do them then go with the Steeda's. This is not a mod you want to go cheap on.

 

On a more positive note, the crank pulley does not appear to be of the piggyback type--I sent the vendor a message asking if they have a photo of the backside of the crank pulley.

OTH, it is difficult to tell from the photo of the crank pulley and balancer are separate components with "rubber" dampening (as it should be), or a single part. I would be wary of a single piece balancer/pulley as neither Ford nor any established after market vendor has chosen to go that way...

 

The vendor sent me a photo of the backside of the crank pulley--which tells me for sure that it is not a piggy-back unit, that the balancer is bonded to the puller hub, and that it appears well made and finished.



Based on this photo and that the crank pulley is SFI approved I'd go for if I had a '96-'01-1/2...

 

after i looked at that ebay page, seems the seller is SLP - wonder if its the same SLP we know that makes exhausts?

i might buy it just for the crank wheel, i need a new crank wheel eventually, the outter edge of mine is chipped up slightly... the only thing i cant use is the water pump pully right?

 

That is correct, however if you do that you will need a different length belt (shorter) and be aware that if you use the stock w/p pulley the pump will be overdriven as compared to using the UDP w/p pulley.

However this is not a problem. The stock crank/pump pulley drive ratio is 1.27:1, an overdrive, meaning that the water pump spins 1.27 times faster then the crank. With UDPs the crank/pump ratio is 0.77:1, and underdrive, slowing the pump to 0.77 time the crank speed.

Using the UDP crank pulley with the OEM water pump pulley will result in a 0.95:1 ratio, still an underdrive, but just not as much as using the UDP pump pulley.

Here's a comparison of the OEM versus UDP water pump speeds:



and if using the UDP crank pulley with the OEM w/p pulley:



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I mapped all this out while making the decision to get UDPs--can't help it, I'm a 3rd generation engineer on my father's side; and my mother's father was an engineer as well...

 

yes i was wondering the same thing when i saw SLP

but do you think it seems like a good bang for your buck hp upgrade for 90$, or would you recommend getting the steeda pullys

 

I would not be hesitant to buy them, the vendor told me:

; and as I said earlier the crank pulley is obviously of high-quality...

 

they sell their GM LS1 crank pulley (and only the crank pulley) for 199.99... so they are high quality.