How do underdrive pulleys increase HP and where can i get some for my 5.0, also I read in Truckin magazine that a mass airflow sensor can increase HP sounds like bullsh#t to me.
I cant say anything for or against the mass air setup. Except that with mass air there is little or no recalibration neccsarry for a blower turbo or just switching around components. Pulles dont really increase hp, the just runn slower. Like the pulleys are just bigger so that everything spins slower. I have heard that some cars overhead after getting pulleys.
They also have charging problem. I know from experiance.
Hey guys i run underdrives on my bird without any problems.
However i prepared for them first.
I installed a 3g alternator(a must when installing underdrives)and raised my idle to 1000rpm like it says in my underdrive instructions and i get 14.6 volts at idle.
That's with my lights,heater on full and my 2100watt rms stereo poundin.
Also installed a 180deg t-stat and my temp gauge always runs at no more than 1/4 gauge.
As for a power diff, they say anywhere from 8-15hp is possible.
Dyno tests have been done and is does prove to be true but do you actually feel that 8-15hp in your ass,doubtfull but it is there and every little bit helps.
Now the above upgrades i recommend to anybody even when not installing underdrives.
A 190deg stat is just to hot in the summer especially when running A/C and lets face it the 2g piece of alternator is not even sufficent for the stock accessories let alone any upgrades.
So i say every hp counts and for under 100.00 dollars it's a worth while investment.