under drive pulley set
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Thread Starter
Drifting
Joined: Dec 2011
Posts: 1,439
Likes: 23
From: mesa az
So far I've heard one person say he believes a gain of 5HP is what a under drive pulley set will provide. My L98. With that said any opinions on deleting the air pump and replacing it with a bracket and wheel ? Same theory.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Let me "share" (PC phrase)....on my 85 I added the March underdrive pulleys and at the same time added a straight thru pipe in place of the cat. I took it to the race track. There were no other changes. The car went from 14.1 to 13.6. And was consistent at 13.6. In hind site I wish I had made one change at a time, but the track is 1.6 hours drive away. The 85 exhaust necks down to a single pipe for the front "Y" into the cat and then out thru the rear "Y" to the mufflers. I was using semi-stock mufflers which had two working exit pipes. Original 85 had two pipe only one exit for each muffler.
Anytime you make a change it all adds up. 2 HP for this 2 HP for that and on and on. Do you need the air pump to pass smog in Arizona? If you do, then I would look to other areas for HP. Perhaps going to 1.6 RR, better exhaust or make the leap to better flowing heads.-
Anytime you make a change it all adds up. 2 HP for this 2 HP for that and on and on. Do you need the air pump to pass smog in Arizona? If you do, then I would look to other areas for HP. Perhaps going to 1.6 RR, better exhaust or make the leap to better flowing heads.-
Last edited by John A. Marker; May 2, 2014 at 01:34 PM.
