Underdrive pulley worth the effort?
Melting Slicks
Joined: May 2000
Posts: 2,974
Likes: 5
From: CenTex Texas
Re: Underdrive pulley worth the effort? (jpvette)
Only if you're getting a cam installed, otherwise it's more of a pain then what it's worth and will only net you about 6-8 rwhp......(10 rwhp is really on the optimistic side).
Melting Slicks
Joined: Sep 1999
Posts: 2,521
Likes: 0
From: Houston, TX
Re: Underdrive pulley worth the effort? (97C5ENVY)
I got 8 peak rwhp and 5 peak rwtq when mine was installed. I'm very happy with the results and would do it again. Since I don't have any plans for major engine work this mod was a good one for me. Here's my dyno sheet. It shows a nice gain across the rev range.
If you have plans for heads and/or cam it'd prolly be smart to wait and do it at the same time.
If you have plans for heads and/or cam it'd prolly be smart to wait and do it at the same time.
Le Mans Master
Joined: Apr 2001
Posts: 5,331
Likes: 39
Re: Underdrive pulley worth the effort? (97C5ENVY)
It's Kind of a pain to install, mainly pulling the steering rack. So If you don't want to do the work it's about $250 labor.
I didn't dyno my car until the mods I have were installed so I can't say how much the pulley added. GM says the factory engine has 345 hp (about 293 rwhp) I dyno'd at 327 rwhp or 385 fwhp.
Ram Air, cat back exhaust, under-drive pulley = 34 rwhp. In my application I think the pulley added more than 10 of that. Also the alternator output is no different than before 13.9-14.5 consistantly.
I didn't dyno my car until the mods I have were installed so I can't say how much the pulley added. GM says the factory engine has 345 hp (about 293 rwhp) I dyno'd at 327 rwhp or 385 fwhp.
Ram Air, cat back exhaust, under-drive pulley = 34 rwhp. In my application I think the pulley added more than 10 of that. Also the alternator output is no different than before 13.9-14.5 consistantly.
Pro
Joined: Mar 2001
Posts: 561
Likes: 0
From: Austin, Texas USA Texas
Re: Underdrive pulley worth the effort? (jpvette)
Quote
......(10 rwhp is really on the optimistic side).
If it is good for 10RWHP then my T1 cam only gained me 10RWHP. This combo neted me 20RWHP.
......(10 rwhp is really on the optimistic side).
If it is good for 10RWHP then my T1 cam only gained me 10RWHP. This combo neted me 20RWHP.
