nathan_hebb

howdy everyone, i have a little 5.0 ive been building for awhile, '93 block, carbed. been hearing alot about these underdrive pullies, what exactly are they and are they beneficial? i drive the car damn near everyday about 40-60 miles an its getting about 19-21 mpg, most of it is highway driving. just wondering if its worth checking out

oldfella

They advertise incrementally increased HP by incrementally decreasing the load that your accessories pull. (i.e. a/c, alternator, power steering, etc) although I do NOT have it on my alternator.

My 5.0 has underdrive pulleys. I can't document this for you.

nathan_hebb

all i have is alternator. so would it even do any good?

bluebeastsrt

Is your water pump electric? Under drive pulleys slow down the ps pump, alt, water pump etc. the theory is less drag more hp.

mjr46

nothing is the point of them.....if you build a motor with enough hp, who needs them?? only those who need to believe they've gain some ponies from them/freed up some ponies better said......lol

nathan_hebb

no my water pump is not electric? theres a serpentine belt going to my alternator and a v belt to the water pump.

nathan_hebb

is it dyno proven numbers or just a theory?

bluebeastsrt

No they work. Their just not worth the 3 horsepower they free up.

9redfox3

I installed a new underdrive crank pulley and new 95 amp alt when I rebuilt my top end!It was already apart so why not ?