Underdrive Pullies - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

PigDog · 11-27-2003, 10:41

Has anyone tried underdrive pullies on a fairly stock 5L? The yanks rave about them so I'm wondering what sort of gains there would be.. Any adverse effects?

XR8 Lamah · 11-27-2003, 13:09

Adverse effects depend on what system you underdrive, and how much. e.g. alternator will drop power ( you might lose charge when you run lots of gear at once), and water might increase your temp, meaning you need better radiator etc.
Usually you can get a fairly happy medium tho (the stock systems have a little extra margin built in).
Not too sure on power gains however.

Heres one thread of info: Underdrive Pulleys

There are a few more if you try a search or two . . .

TwinPiston · 11-27-2003, 14:40

I know there is a Ford Motorsport Set around brisbane somewhere, they are suppose to fit.

blueoval · 11-27-2003, 14:50

I like the thought of this except running the alternator at lower volts. Is this dangerous? Will there be any undue stress on other components?

TwinPiston · 11-27-2003, 15:38

It is supposidly better as the ancillilaries run slower and therefore the life of these is extended. It should only be a problem if you run big steroes at idle.

dodgie · 11-28-2003, 08:18

I have a crank under drive pulley purchased from Battens Performance Tuning for my 5.0l.
http://www.norcom.net.au/~bpt/index.html

PigDog · 11-28-2003, 08:25

Thanks Dodgie, that's the one i've been looing at. I sent them an email but no response so far. Did you find much improvement from it and how much did $$$? How's the alternator charge and water temp?

dodgie · 11-28-2003, 08:53

They may take a few days to respond, but barry batten is helpfull.
I can't recall the pulley price (round $140-150+postage)
you will need another drive belt also.
I picked my belt up from B.S.C. motion tech (bearings/belts specialist)as it was cheaper to do this than buy one from battens(I also get trade price),just ask for a part number for the belt from Battens, they were more than happy to help me out.
A small improvement in the seat of the pants, main benafit is you wont be thrashing your power steering pump etc.
Voltage can drop a bit if your idling with an amp pumping out rockabilly...(or swing!)
My water temps were fine, but I have thermos with an adjustable thermostat switch,and a 180deg coolant thermostat.
I had to cut my crank pulley bolt off with a grinder/cutting disc as the B!^ch of a thing wouldnt budge,apart from that it is an easy mod to do

EDXR8 · 11-28-2003, 22:27

I also run the Batten Performance one and am very happy with it. The pulley was $165 and the belt was $80 but that may have changed by now. You can't really get a better $$$ for kw mod than the underdrive pullies.

PigDog · 11-28-2003, 22:40

Thanks for the responses guys!