Underdrive pulleys
 

Hi,
Curious what the consensus is for replacing the underdrive pulleys on an '89 LX 5.0L?

I've heard possible overheating problems or issues with the alternator.

I have an electric fan to install to help with the overheating problem.

Any suggestions good or bad? I just don't want to do a simple mod that will cause massive problems for me later. I'm just looking for a little more horse. Is 15 - 20 hp worth it on an AOD '89 5.0L?

Thanks,
Justin

The March Performance 'Power and Amp' series billet aluminum pulleys are claimed to cure the issues associated with utilizing underdriven accessories while still freeing up 10hp to the wheels, though I can't back up the claim personally... it's food for thought ;)

I have the March *Power and Amp* pulleys on my 91 5.0 AOD, and so far have had no problems with them. The only thing I noticed after putting them on was that my car started to run a little hot in 95*+ weather. But thats nothing a 180* thermostat can't fix! As for the hp increase, my car seemed to run a bit smoother, and I could feel it pull harder past 4000rpms. one thing I wouldn't recommend doing is running an electric fan with underdrive pulleys if you still have the stock alternator. You usually need a 130amp alt. when running both.

THe pulleys are worth an honest 7rwhp, seen it myself!

You _may_ experience some charging/cooling issues, depending on what underdrive percentage you go...

Now thats what they want you to belive
 

Come on , I no it's tough after you have bought something !
To dipute the claim ? But you are talking to some one now that
has never seen this ! I've had 7 different pulley systems on 5 stangs.
And it just was not there . Sorry ,maybe i was making to much H/P to notice ,don't think so , Maybe it was the shitty amp meter reading i was getting all those years in defferent stangs ? maybe ! but you no what ,there ain't a difference with those stock pulleys .. And your stang will love you for it .
;)

Unless you are driving around with the tach at the upper end all the time, you won't notice a thing. Well, actually you will notice your lights dimming at night when at idle and the temperature guage reading hotter when in stop-and-go traffic. I thought they sucked (even had the March pulleys) so I tossed them long ago. With my current combo, I doubt they would make a difference. I now run the '93 Cobra crank pulley with the matching water pump pulley (which is SMALLER) to keep the coolant flowing. My 3G alternator also has the OEM '94 pulley. Just my $.02.