Under Drive Pullies?
Not worthwhile, not a bad an idea as the granatelli and more reliable than the MSD opti though. Still I would skip it unlress you road race then the lower rpms for the power steering are good to delay overheating.
UD pullies work best on vehicles with belt driven waterpumps.
UD pullies work best on vehicles with belt driven waterpumps.
Pulling the belt is worth about .1 at the track so it stands to reason underdriving the acessories would be worth whatever the UD percentage is. Far as I know the most aggressive UD setup is a .34ud and .34 of .1 seconds is .034 at the track. If anyone sees a flaw in my SCIENCE please speak up. People convince themselves of gains that are not there, we have all done it at some point.
Really since the pullies add a miniscule amount of weight I do not believe you would see the full .034 gain.
Another possibility is I know there have been guys who put the pullies on and left the 12lbs damper off and reported a gain and that is a real gain but comes at the cost of harmonics slowly destroying the bottomend.
Really since the pullies add a miniscule amount of weight I do not believe you would see the full .034 gain.
Another possibility is I know there have been guys who put the pullies on and left the 12lbs damper off and reported a gain and that is a real gain but comes at the cost of harmonics slowly destroying the bottomend.
They are probably worth a couple hp. The biggest problem I had was my electrical system not charging right, even with the alternator. I think there may have been a problem with my system though, because with the alternator pulley it should have been fine. They are real cheap, so I wouldn't say they aren't worth it, but they will only give a minimal gain.
Trending Topics
i have the march and literally gained a whopping 6 ponies and 8 ft lbs. the main difference is that it speeps up ur alternator which isnt good for any alternator but u will get more amperage out of it. which i need for a lot of electrical goodies i have on my car. but hey its personal preferance and money that u will need to spend $100 there or $100 saved towards a n20 kit
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
I had ran an ASP 23% underdrive pulley (replaces stock balancer) on my H/C 350 and had no issues.
I run a stock-style battery, EWP and typical sound setup.
I won't run it on my new 383 since I'll be running an aftermarket harmonic balancer.
(fluidampr or otherwise); I have not decided yet
Crank-only works well if you have a stroker with >850rpm idle; use the 2-pulley setup if you have a stock idle.
You will free up a few HP and it certainly does rev quicker without the AC and PS dragging it down so much.
If you have eliminated one (or both) of those or race beltless, the UD won't really do much for you.
I can't think of any setup that would spin the Alternator faster than stock,
the 2-pulley setup is designed to bring the speed back to stock, maybe a little slower,
but certainly not any faster. That would be a silly thing to do.
I run a stock-style battery, EWP and typical sound setup.
I won't run it on my new 383 since I'll be running an aftermarket harmonic balancer.
(fluidampr or otherwise); I have not decided yet
Crank-only works well if you have a stroker with >850rpm idle; use the 2-pulley setup if you have a stock idle.
You will free up a few HP and it certainly does rev quicker without the AC and PS dragging it down so much.
If you have eliminated one (or both) of those or race beltless, the UD won't really do much for you.
I can't think of any setup that would spin the Alternator faster than stock,
the 2-pulley setup is designed to bring the speed back to stock, maybe a little slower,
but certainly not any faster. That would be a silly thing to do.