Underdrive pulley on cars

Fastback. lol

I know people say they do bad things to the car because the rotation isn't the same as stock and it can lead to overheating or even electrical issues.

My primary question is not what goes wrong and how but rather how come this works perfectly for some people?

If it is a bad concept to he treated like some scam ebay electric supercharger them how comes it works for some people with the added benefits?

Is it the pulley you choose? Selecting the correct belts? Is it human error in the process of it? Or is it just random luck that it works or fails?

Curious why someone can have one on their car for 50,000 miles with no issues and other people break their cars due to them.

Thanks.

Well they decrease drag on the crank and take less hp to turn your accessories. We are talking pretty minimal gains here in a street application. So it's kinda a cost vs effectiveness issue in most cases . If you buy a set from a reputable company and fallow the recommendations then you should have no issues most times. * if your car is in good running order.

Less drag = more hp/tq.

Was SOP back in the day for 5.0s

TFK_Mas Tisu -


Was SOP back in the day for 5.0s

Still is on new ones .

Fastnotch yet ? The forum defreshes you know..

First post. I see seven replies yet I click on the thread and only see the op. Terrific.

fastnotch331 - Well they decrease drag on the crank and take less hp to turn your accessories. We are talking pretty minimal gains here in a street application. So it's kinda a cost vs effectiveness issue in most cases . If you buy a set from a reputable company and fallow the recommendations then you should have no issues most times. * if your car is in good running order.
You have any connections in San Diego ? My little old toyota needs some tlc :(

Aaronrodgers=GOAT - Fastnotch yet ? The forum defreshes you know..
Ya kirik needs to fix this shit .

Oh and stop caking me fastback . My shit has a trunk .

The rewards are small hp increases that you probably cant feel. Downside is less cooling and possible under charging of battery or unable to power extra electronics. It probably depends on the pully ratio you go to. It doesn't seem worth it unless your drag racing the car in a certain class. Probably a small decrease in ratio would work ok.

Aaronrodgers=GOAT -
fastnotch331 - Well they decrease drag on the crank and take less hp to turn your accessories. We are talking pretty minimal gains here in a street application. So it's kinda a cost vs effectiveness issue in most cases . If you buy a set from a reputable company and fallow the recommendations then you should have no issues most times. * if your car is in good running order.
You have any connections in San Diego ? My little old toyota needs some tlc :(
Sorry man, I know a couple people in norcal Sacramento, Folsom , orangevale. Might still have some in the bay area I'd have to reach out to confirm though . I know probably doesn't help .

jpm995 -

The rewards are small hp increases that you probably cant feel. Downside is less cooling and possible under charging of battery or unable to power extra electronics. It probably depends on the pully ratio you go to. It doesn't seem worth it unless your drag racing the car in a certain class. Probably a small decrease in ratio would work ok.

Yep . Most companies offer a street under drive set up , but you know how kids are they gotta buy the super cool guy race shit and have problems because its too underdriven for regular driving . I was dumb and you once too lol.

^young * man auto correct is bad today.

fastnotch331 -
jpm995 -

The rewards are small hp increases that you probably cant feel. Downside is less cooling and possible under charging of battery or unable to power extra electronics. It probably depends on the pully ratio you go to. It doesn't seem worth it unless your drag racing the car in a certain class. Probably a small decrease in ratio would work ok.

Yep . Most companies offer a street under drive set up , but you know how kids are they gotta buy the super cool guy race shit and have problems because its too underdriven for regular driving . I was dumb and you once too lol.

Anything you do on your own call is cool. I helped my grandson paint the wheels/brakes on his 2003 mitsu lancer. Ruined wheel bearing getting rusted on wheel off and snapped shift lever getting factory knob off but he likes the car much better and the white wheels do look pretty good.

jpm995 -
fastnotch331 -
jpm995 -

The rewards are small hp increases that you probably cant feel. Downside is less cooling and possible under charging of battery or unable to power extra electronics. It probably depends on the pully ratio you go to. It doesn't seem worth it unless your drag racing the car in a certain class. Probably a small decrease in ratio would work ok.

Yep . Most companies offer a street under drive set up , but you know how kids are they gotta buy the super cool guy race shit and have problems because its too underdriven for regular driving . I was dumb and you once too lol.

Anything you do on your own call is cool. I helped my grandson paint the wheels/brakes on his 2003 mitsu lancer. Ruined wheel bearing getting rusted on wheel off and snapped shift lever getting factory knob off but he likes the car much better and the white wheels do look pretty good.

For sure man , how's the vette?

fastnotch331 - Oh and stop caking me fastback . My shit has a trunk .
Fuck, I'm full potato. My bad. lol

I'm OK with minimal gains on a car with little to no aftermarket parts. If I get 7 to 10 hp to the crank I'm very happy for what would be a 100 purchase or so with different belts.

I already bought one a few months ago. Just waiting for better weather. It just confused me as to why people have problems and others don't. Most things that work do so for a reason much like things that fail do so for a reason. Hard to understand why it works for some and not others.

The crank pulley in mine is old and they tend to separate at this age so I was going to replace it anyways. Figured I would go with something that gives minimal gain at the same time. Already replaced idler pulley and the alternator pulley is brand new hooked up to a HO 160 amp alternator.

Sitting in the garage, winter in NY. I'll be crusing soon just got cataract/lens replaced, went from 20-400 to 20-40 in right eye. In March left eye gets done and i'll be driving more. That car is just a blast to drive.

Cotton - I'm OK with minimal gains on a car with little to no aftermarket parts. If I get 7 to 10 hp to the crank I'm very happy for what would be a 100 purchase or so with different belts.

I already bought one a few months ago. Just waiting for better weather. It just confused me as to why people have problems and others don't. Most things that work do so for a reason much like things that fail do so for a reason. Hard to understand why it works for some and not others.

The crank pulley in mine is old and they tend to separate at this age so I was going to replace it anyways. Figured I would go with something that gives minimal gain at the same time. Already replaced idler pulley and the alternator pulley is brand new hooked up to a HO 160 amp alternator.
There are several reasons they can cause issues, like jpm listed . But more often then not with a heating issue its because the cooling system is already not working efficiently /properly. With not charging as he mentioned its usually from picking a set up that isn't intended for street use to begin with . If you buy from a reputable company and get their street style pulleys you shouldn't have a problem if everything else is functioning as it should. Part of most failures is either wrong choice (full race ) or cheap junk products.