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

SiZzOuRcE · 11-29-2005, 17:16

Hey, after doing a little research, I've come to the conclusion that MAC is the same quality as Steeda as far as underdrive pulley kits.

I found this website: http://www.v8power.com/cat--MAC-Performance--macp.html

As you can see it has a few different kits, the only problem Im running into is figuring out which goes with my car 94 GM.

Can anyone tell me which kit I need for my car, they are so cheap they are just screaming my name to buy them. Thanks.

BlueSteel · 11-29-2005, 21:59

94-95 4.6L mustang should work, same engine (aside from brain and internal parts). Honestly, I don't like underdrive kits unless you do a ton of drag strip, I'm told they are a pain in daily drivers. Helped put one on a 1993 mustang daily driver, we put a new die hard battery in it and a melling aluminum water pump (it called for a 3-5/16" blade). The battery always went under voltage and the engine got real hot, maybe it was the type of under drive kit, I'm not sure.

SiZzOuRcE · 11-30-2005, 12:39

The only bad things that I heard about them was that when you are driving at night, the lights seem to fade out when not driving fast and the inside lights, LEDs and whatever else fade in and out.

I don't understand that battery thing however, because it doesn't have anything to do with your battery after start up. Also, why would the engine get really hot?

SiZzOuRcE · 11-30-2005, 12:41

Also, while I was looking around to find a better deal, I found this site: http://store.wpsracing.com/macunpusefor.html and it says the 1994-95 is for a 5.0 motor. I think I need the 1996-1998 set.

ryoder · 11-30-2005, 14:50

After startup the car runs off of the alternator, it's not turning as fast ,thats the reason for the fade in the lights and such, also the water pump is not turning as fast as it would with the regular pulleys and thats the reason for overheating. Unless you got a 130 amp alternator and a high volume water pump , underdrive pulleys will create problems for a crown vic. They are geared too high for such things.

RAVEN · 11-30-2005, 16:13

Underdrive Pulleys? What r they?

BlueSteel · 11-30-2005, 16:24

They reduce the speed of the alternatot, water pump, and sometimes the A/C pump inorder for free up a few horse. They are nothing but problems on daily drivers, but on high performance cars like mustang, lightening, and such, they will free up more power, but you might aswell remove your head lights and carrier flash lights :) Also it recomended you paint you rear bumper with reflective paint :D

RAVEN · 11-30-2005, 16:40

Thanks mate.

SiZzOuRcE · 11-30-2005, 18:43

So basically your telling me not to spend $100 and buy them. I've heard of some people keeping the stock water pump pulley on until they hit the track. I really need to start beefin this car up before I sell it. It really let me down when I got whipped by a 04 Pontiact Sunfire with intake. Thats just straight up sad.

ryoder · 11-30-2005, 21:56

My Opinion, headers,cold air intake, P71 computer from the salvage yard(it's cheaper than getting a chip and does relatively the same thing) and thats it. I did that and could tell a big difference right away. Of course mine is a intercepter so I didn't have to get a computer,but,I would forget the pulleys...they're not worth it.This way is the most bang for the buck