Today I was told that I should not get an underdrive pulley because it doesn't have a balancer on it so it can ruin the oil pump. Could some one fill me in please.

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would I use the stock bolt with the AF/X Pulley?

Yes (regarding the bolt).

My machine shop told me the same thing regarding the harmonic balancer. I had some issues w/ cracking oil pump rotors and he 'beleives' this was a result of that very issue. There are TONS of guys on here that run the afx udp w/o having anything like the problems I ran into. Judging by the success on here and in the neon world i'd say its safe to use, else Howell probably wouldn't be selling them for as long as they have.

400whp or bust.

Don't worry, be happy. Help yourself to an AF/X UDP or another name brand. I have changed my tune a little bit about the E-bay ones. No, I don't recommend getting one, but not for a balance reason as much as a warpage reason. You may have a problem with belts if you go E-bay.

This question comes up once in awhile on the Neon forums, also (just came up again recently). I get a chuckle out of the one or two people who say they don't like them because some machinist in a shop told them about a Mustang that blew up the block because of the UDP etc. They say this in the face of extensive, emperical (damn I'm using that word a lot lately) evidence of 2gnt's and Neons.

Captain Caveman

96 RS Turbo 11.414 @ 119.62 MSNS, Crower 2 NA cams, BW366, 10.5 comp, UDP, 60mm TB, W/A intercooler, 3.55 tranny 567.9whp 430tq
97 RS NA 13.188 @ 103.87 MSnS powered 12.5 comp, Crower 3's and 219.4whp with 175tq
98 RS DD 12.5 comp on stock ECU, LTH, Crower 2's, Koni, GC, Hypercoil, DG hats
99 OZ 5sp Stocker 15.856 @ 85.97
99 GS stocker auto 17.7@77mph!

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Thanks for all the replys i'm just going to throw it on... i got it for free so what the hell.