the truth about pullies please?

pearlgt · 06-10-2003, 02:17 PM

I just got my first gt mustangs

and looking for the truth about underdrive pullies Im hearing for the money that the are a great mod also what about a mac cold air kit (fenderwell) I want my car to run mid to high 12's but it is my daily driver please help thanks

WADS56 · 06-10-2003, 02:30 PM

Pullies do free up some hp but can cause more of a headache then there worth. They were on my 93 and were causing charging problems at idle, and the ac wouldn't be as cold at idle also. I replaced them with stock pullies and it was all fixed but I did notice the car lost a little pep.
I wouldn't get a CAI till you do some induction mods (MAF, TB, intake). Just remove the air silencer and you just bought yourself a CAI.
IMO you should spend the money for the pullies and CAI on a set of new gears

06-10-2003, 02:34 PM

What year is your stang? Since it sounds like your car is stock, you will definitely benefit from underdrive pullies. They help the motor run through the rpms faster for sure. The main drawback is that they turn the alternator & water pump a little slower, so if you are doing a lot of driving in traffic or even idleing at a stop light your headlights & dash lights may dim some (if you're driving at night) and your amps will drop down some. And if it's a really hot day and you are stuck in bumper to bumper traffic there is a chance of overheating due to the fact that the water pump is turning slower than stock at an idle. In my opinion you'll be fine though. It's worth the small risk of driveability problems...& definitely worth the $$!

silver_pilate · 06-10-2003, 02:38 PM

Well, I agree with WADS56. I installed some pullies on the GT a while back. I then experienced cooling problems not only at idle, but occasionaly on the freeway as well. Of course, I live in thin air (high altitude) with little or no humidity, and during the summer, temps range from 90 to 110. I swapped back to the stock water pump pulley and this helped. However, I still have occasional problems, especially in traffic. I'm about to swap back to the stock crank pulley as well. Also, at night the output of the alternator drops pretty low with the lights and vent going.

Anyway, pullies will free up a couple of horsepower for you. Expect about 5-10 hp. However, don't overlook the potential side effects. Of course, there will be others who have never had any issues whatsoever with pullies.

I concur with WADS56 on the gears suggestion as well. They will have a significant impact on the acceleration of your vehicle without increasing horsepower. And, if you really want mid 12's, you will need gears. 3.37's for a T-5 and 4.10's for an AOD is what I suggest.

--nathan

pearlgt · 06-10-2003, 02:40 PM

THANKS FOR THE ADVICE, I JUST RAN AN OFFROAD H PIPE WITH TWO CHAMBER FLOWS NOW TRYING TO FIND OUT WHAT TO PURCHASE NEXT, I HAVE A SET OF 373 WITH AN AUBURN UNIT COMING FOR THE CAR (IT IS A FIVE SPEED) AGAIN THIS IS MY FIRST GT SO ANY INFO IS HELPFUL THROTTLE BODY THINGS LIKE THAT THANKS FOR THE FEEDBACK GUYS

bigred90gt · 06-10-2003, 04:30 PM

I did notice a little bit of pep, but not a drastic difference. I have never had cooling issues to the point where I thought it was going to over heat. It does tend to run hotter than it did, but never above normal. As far as charging, I had 3 amps, 1 - 15" sub, 2 - 6x9's, 2 - 5x7's and 2 - 3 1/2's and a crossover in my car and never had a dead battery. My lights would dim a little when I stopped, but it wasnt noticeable until I revved or took off. The CAI is garbage on a pretty much stock car. The only thing it has done for me is, it whistles when you hit the gas because of the air running through the filter and it sounds kind of cool. That didnt start until I got my TB though. And people say on a car with the stock intake and heads, anything over 65mm TB will kill low end, but my times improved a little (maybe .05 to .1) when I installed it. With better flowing heads and intake, the TB is a must. I say get some headers too. You can pick them up on ebay for a good price. I got mine used at a speed shop for $70. Hope this helps and congrats on the purchase.

Caymon

jimberg · 06-10-2003, 06:17 PM

Re: CAIs

Mustangs already come with cold air intakes. The only bottleneck is the air tube. If you replace that with a rigid pipe, it'll be just as good if not better. Just make sure you get a K&N filter.

raptor · 06-10-2003, 10:26 PM

Mods 1st to last under $500 gears, k&n filter, Pro-m maf 77mm 65mm throttlebody,bore egr spacer and upper intake to match t/b, advance timing to 16use 94octane, 160f thermostat, underdrive pullies.....I only use the crank and water pump pullies the altenator didn't turn fast enough. fuel pump, adjustable fuel pressure reg. I think thats all the cheap easy stuff I know of.

Joe50 · 06-11-2003, 08:56 AM

Raptor...you are making matters worse by not using the alternator pulley...the alternator pulley from the underdrive pulleys should be smaller than stock - which actually speeds the alternator back up. This is the first thing they teach you in Machine Design.

raptor · 06-11-2003, 10:56 AM

Sorry its the water pump pulley I don't use. Had to go look at the car

jimberg · 06-11-2003, 11:00 AM

So it's your water pump that's turning slower than it should.

raptor · 06-11-2003, 11:16 AM

Well now you really got me thinking. So I got my old pullies out and compared them. I don't use the altenator pulley. Like I first said. The stock one is smaller=more rpm=charging. The FMS crank pulley is way smaller and the FMS water pump is larger.

jimberg · 06-11-2003, 05:31 PM

Sorry, I was wrong. I realized it after I hit the post button and it was too late. I then tried to erase it and that didn't work. Yes, the water pump pulley is bigger.

302 LX Eric · 06-12-2003, 07:52 AM

I've had a same set of March pullies on my car for the last seven years without any issues. Even have the same stock alternator and Ford Motorcraft Silver battery that was new 7 years ago too.

Yes, your battery gauge will read lower at idle than with the stock pullies, but it's never been an issue for me.

E

Jthompson · 06-12-2003, 05:05 PM

I have a set of mac underdrives on what is now my parts car. It also had a high flow water pump to compensate for the cooling issues. I only ran the car for a month, but the damn thin would never warm up and go past the first white line.

Philossifer · 06-13-2003, 08:15 AM

Quote:

Originally posted by Joe50
the alternator pulley from the underdrive pulleys should be smaller than stock - which actually speeds the alternator back up

Joe50,
I have a set of March, PowderCoated Black, Underdrive pullies and the alternator pulley that came with this kit is larger than the stock one!

The March pullies have a smaller than stock crank pulley, a larger than stock alternator pulley and and larger than stock water pump pulley!

I went back to the stock pulley on the alternator becuase of charging problems. No problems now unless I'm idling for a long time at night with the headlights on, A/C on and the CD player kicking it out!
Phil

Hozer 88GTConv · 06-13-2003, 08:34 AM

After putting the underdrives on, I just got a powermaster 140-amp alt to end the issue.

horsepower and amperage...sweet

BilLster · 06-16-2003, 05:46 PM

after adding wetter water i never have had a over heating problem but do have a problem getting to temp sometimes.

i also want to add a better alternator but i will always go with pulleys on my motors just cause.

electric fan also helps.

06-10-2003, 02:17 PM	#1
pearlgt Registered Member Join Date: Jun 2003 Location: Augusta Georgia Posts: 55	the truth about pullies please? I just got my first gt mustangs and looking for the truth about underdrive pullies Im hearing for the money that the are a great mod also what about a mac cold air kit (fenderwell) I want my car to run mid to high 12's but it is my daily driver please help thanks

06-10-2003, 02:30 PM	#2
WADS56 gear banger Join Date: Aug 2000 Location: CHICAGO Posts: 1,144	Pullies do free up some hp but can cause more of a headache then there worth. They were on my 93 and were causing charging problems at idle, and the ac wouldn't be as cold at idle also. I replaced them with stock pullies and it was all fixed but I did notice the car lost a little pep. I wouldn't get a CAI till you do some induction mods (MAF, TB, intake). Just remove the air silencer and you just bought yourself a CAI. IMO you should spend the money for the pullies and CAI on a set of new gears __________________ 79 Hatch: NA 347, Stage 2 Canfield Heads, Victor JR. Intake, Blueprinted Holley 750 HP, Solid Roller Cam, Shooting for 10's on motor 93 LX: Tremec, dual friction clutch, fms flywheel, Hedman shorties, O/R H-pipe Ricer hater's club member #49

06-10-2003, 02:34 PM	#3
Simi Stang Guest Posts: n/a	pullies What year is your stang? Since it sounds like your car is stock, you will definitely benefit from underdrive pullies. They help the motor run through the rpms faster for sure. The main drawback is that they turn the alternator & water pump a little slower, so if you are doing a lot of driving in traffic or even idleing at a stop light your headlights & dash lights may dim some (if you're driving at night) and your amps will drop down some. And if it's a really hot day and you are stuck in bumper to bumper traffic there is a chance of overheating due to the fact that the water pump is turning slower than stock at an idle. In my opinion you'll be fine though. It's worth the small risk of driveability problems...& definitely worth the $$!

06-10-2003, 02:38 PM	#4
silver_pilate DURKA DURKA!! Join Date: Sep 1997 Location: Lubbock, TX...(TX panhandle) Posts: 1,418	Well, I agree with WADS56. I installed some pullies on the GT a while back. I then experienced cooling problems not only at idle, but occasionaly on the freeway as well. Of course, I live in thin air (high altitude) with little or no humidity, and during the summer, temps range from 90 to 110. I swapped back to the stock water pump pulley and this helped. However, I still have occasional problems, especially in traffic. I'm about to swap back to the stock crank pulley as well. Also, at night the output of the alternator drops pretty low with the lights and vent going. Anyway, pullies will free up a couple of horsepower for you. Expect about 5-10 hp. However, don't overlook the potential side effects. Of course, there will be others who have never had any issues whatsoever with pullies. I concur with WADS56 on the gears suggestion as well. They will have a significant impact on the acceleration of your vehicle without increasing horsepower. And, if you really want mid 12's, you will need gears. 3.37's for a T-5 and 4.10's for an AOD is what I suggest. --nathan __________________ '91 GT, Coast 347, 9.5:1 compression, full intake, Wolverine 1087 cam, exhaust, Keith Craft ported Windsor Jr. Irons (235 cfm intake, 195 cfm exhaust), AOD, PI 3500 converter, Lentech valve body, 3.73's (4.10's in the works), and Yokohama ES100's out back. Daily Car: '04 Infiniti G35 Sedan 6MT

06-10-2003, 04:30 PM	#6
bigred90gt 2 Stangs in the Stable Join Date: Apr 2002 Location: Baytown, TX Posts: 1,209	I did notice a little bit of pep, but not a drastic difference. I have never had cooling issues to the point where I thought it was going to over heat. It does tend to run hotter than it did, but never above normal. As far as charging, I had 3 amps, 1 - 15" sub, 2 - 6x9's, 2 - 5x7's and 2 - 3 1/2's and a crossover in my car and never had a dead battery. My lights would dim a little when I stopped, but it wasnt noticeable until I revved or took off. The CAI is garbage on a pretty much stock car. The only thing it has done for me is, it whistles when you hit the gas because of the air running through the filter and it sounds kind of cool. That didnt start until I got my TB though. And people say on a car with the stock intake and heads, anything over 65mm TB will kill low end, but my times improved a little (maybe .05 to .1) when I installed it. With better flowing heads and intake, the TB is a must. I say get some headers too. You can pick them up on ebay for a good price. I got mine used at a speed shop for $70. Hope this helps and congrats on the purchase. Caymon __________________ '90 GT Under construction Best E.T. = Fast @ High Speeds - OK So I Lie. So What!!! 04 F-150 STX 4.2L 5 spd Rice Haters Club Member #128

06-10-2003, 02:40 PM	#5
pearlgt Registered Member Join Date: Jun 2003 Location: Augusta Georgia Posts: 55	THANKS FOR THE ADVICE, I JUST RAN AN OFFROAD H PIPE WITH TWO CHAMBER FLOWS NOW TRYING TO FIND OUT WHAT TO PURCHASE NEXT, I HAVE A SET OF 373 WITH AN AUBURN UNIT COMING FOR THE CAR (IT IS A FIVE SPEED) AGAIN THIS IS MY FIRST GT SO ANY INFO IS HELPFUL THROTTLE BODY THINGS LIKE THAT THANKS FOR THE FEEDBACK GUYS

06-10-2003, 06:17 PM	#7
jimberg Registered Member Join Date: Oct 1998 Location: Rogers, MN Posts: 2,089	Re: CAIs Mustangs already come with cold air intakes. The only bottleneck is the air tube. If you replace that with a rigid pipe, it'll be just as good if not better. Just make sure you get a K&N filter. __________________ 351W 89 Mustang GT Convertible

06-10-2003, 10:26 PM	#8
raptor Registered Member Join Date: Sep 1999 Location: Dundalk, Ont, Canada Posts: 129	Mods 1st to last under $500 gears, k&n filter, Pro-m maf 77mm 65mm throttlebody,bore egr spacer and upper intake to match t/b, advance timing to 16use 94octane, 160f thermostat, underdrive pullies.....I only use the crank and water pump pullies the altenator didn't turn fast enough. fuel pump, adjustable fuel pressure reg. I think thats all the cheap easy stuff I know of. __________________ 88GT, 331Stroker,FMS 70mm TB,77mm Pro-M mass air,Ram Air,K&N,GT40/Exployer Intakes,Gasket Matched,FMS 24lb injectors,Crane hi-6 ignition system,B303 cam,Crane 1.6RR,FMS underdrive pullies,351W/heads,port/polish,FMS h/f oil pump,Hedman headers,2 1/2in H pipe Flow Masters,190lph Holley fuel pump,Center Force dual friction,FMS 3.55,Hurst short throw/ trigger T handle,Subframe connectors,Welded torque boxes.

06-11-2003, 08:56 AM	#9
Joe50 Registered Member Join Date: Jan 2000 Location: Newport News, VA Posts: 78	Raptor...you are making matters worse by not using the alternator pulley...the alternator pulley from the underdrive pulleys should be smaller than stock - which actually speeds the alternator back up. This is the first thing they teach you in Machine Design. __________________ "Drive it like you stole it!" '94 Vibrant Red GT

06-11-2003, 10:56 AM	#10
raptor Registered Member Join Date: Sep 1999 Location: Dundalk, Ont, Canada Posts: 129	Sorry its the water pump pulley I don't use. Had to go look at the car __________________ 88GT, 331Stroker,FMS 70mm TB,77mm Pro-M mass air,Ram Air,K&N,GT40/Exployer Intakes,Gasket Matched,FMS 24lb injectors,Crane hi-6 ignition system,B303 cam,Crane 1.6RR,FMS underdrive pullies,351W/heads,port/polish,FMS h/f oil pump,Hedman headers,2 1/2in H pipe Flow Masters,190lph Holley fuel pump,Center Force dual friction,FMS 3.55,Hurst short throw/ trigger T handle,Subframe connectors,Welded torque boxes.

06-11-2003, 11:00 AM	#11
jimberg Registered Member Join Date: Oct 1998 Location: Rogers, MN Posts: 2,089	So it's your water pump that's turning slower than it should. __________________ 351W 89 Mustang GT Convertible

06-11-2003, 11:16 AM	#12
raptor Registered Member Join Date: Sep 1999 Location: Dundalk, Ont, Canada Posts: 129	Well now you really got me thinking. So I got my old pullies out and compared them. I don't use the altenator pulley. Like I first said. The stock one is smaller=more rpm=charging. The FMS crank pulley is way smaller and the FMS water pump is larger. __________________ 88GT, 331Stroker,FMS 70mm TB,77mm Pro-M mass air,Ram Air,K&N,GT40/Exployer Intakes,Gasket Matched,FMS 24lb injectors,Crane hi-6 ignition system,B303 cam,Crane 1.6RR,FMS underdrive pullies,351W/heads,port/polish,FMS h/f oil pump,Hedman headers,2 1/2in H pipe Flow Masters,190lph Holley fuel pump,Center Force dual friction,FMS 3.55,Hurst short throw/ trigger T handle,Subframe connectors,Welded torque boxes.

06-11-2003, 05:31 PM	#13
jimberg Registered Member Join Date: Oct 1998 Location: Rogers, MN Posts: 2,089	Sorry, I was wrong. I realized it after I hit the post button and it was too late. I then tried to erase it and that didn't work. Yes, the water pump pulley is bigger. __________________ 351W 89 Mustang GT Convertible

06-12-2003, 07:52 AM	#14
302 LX Eric or '331 LX Eric' Join Date: Jan 1999 Location: Columbus, Ohio Posts: 2,142	I've had a same set of March pullies on my car for the last seven years without any issues. Even have the same stock alternator and Ford Motorcraft Silver battery that was new 7 years ago too. Yes, your battery gauge will read lower at idle than with the stock pullies, but it's never been an issue for me. E __________________ 1991 5.0 LX Coupe - 40,750 miles 331 cu. in. / Tremec 3550 / BFG Drag Radials 12.22 @ 114.31 mph - w/1.89 60'

06-12-2003, 05:05 PM	#15
Jthompson Registered Member Join Date: Sep 2002 Location: Corona, Ca. Posts: 80	I have a set of mac underdrives on what is now my parts car. It also had a high flow water pump to compensate for the cooling issues. I only ran the car for a month, but the damn thin would never warm up and go past the first white line. __________________ Jeremy 1986 Mustang GT Convertible 1972 2 door 302 Maverick 1994 POS head gasket clubbed broke down T-bird with $6000 left to pay off

06-13-2003, 08:34 AM	#17
Hozer 88GTConv Registered Member Join Date: Feb 2002 Location: Jacksonville, FL Posts: 706	powermaster... After putting the underdrives on, I just got a powermaster 140-amp alt to end the issue. horsepower and amperage...sweet __________________ 1988 GT Convertible 331 10:1 TW heads, GT-40 intake, MSD, TRW flattops, B Cam w/ 1.7's, MAC exhaust, 24's, 70 TB, 76 MAF, 3.73's, Pro 5.0, Koni's, Anderson PMS, Wideband 02, yatta, yatta... One week with new motor, two speeding tickets...joy

06-16-2003, 05:46 PM	#18
BilLster Registered Member Join Date: Oct 2000 Location: Ontario canada Posts: 446	after adding wetter water i never have had a over heating problem but do have a problem getting to temp sometimes. i also want to add a better alternator but i will always go with pulleys on my motors just cause. electric fan also helps. __________________ 89 with 331 t3'/t4 hybrids. upr Suspention worked out finnaly . 9.89 144 mph .

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