aem pullys
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From: so cal djmota=oscar
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the difference is wieght on the crankshaft. The reduction of wieght at the crank will give you more gains then just underdriving the accesories.
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From: SoCal
Rep Power: 0 There is a fundamental difference between the DH style (lightweight) pulley and the AEM style (underdrive) pulley.
The DH pulley is the same diameter as the stock Honda pulley. They claim horsepower is gained because it takes less energy to spin it up and this is a reasonable assertion. However, the alternator and P/S are driven at normal speed so there is no gain there.
The AEM pulleys are for the Alternator and the P/S pump. They are larger diameter which makes the accessories spin at a slower speed, thus consuming less power.
The DH style does not decrease any steady state parasitic loss in the engine, it only reduces the losses required to spin up the dampner. It will show it's best gains when the engine speed is increasing at it's most rapid rate. It would show no gain at a steady engine speed (like climbing a hill). That's not my opinion, that's physics. Dyno charts would show the best gain in 1st, and essentially no gain in 5th. So called "back to back" dyno pulls that were performed in different gears would be totally useless at best and intentionally deceptive at worst. I would love to see back to back tests in 1st gear and in 5th gear, that would illustrate the point very well.
The AEM would show an increase net HP gain while the engine is accelerating and while the engine is operating at steady state.
You could always use both if you want, they are not exclusive to each other.
I have the AEM and believe in it but I would not be averse to using both.
The DH pulley is the same diameter as the stock Honda pulley. They claim horsepower is gained because it takes less energy to spin it up and this is a reasonable assertion. However, the alternator and P/S are driven at normal speed so there is no gain there.
The AEM pulleys are for the Alternator and the P/S pump. They are larger diameter which makes the accessories spin at a slower speed, thus consuming less power.
The DH style does not decrease any steady state parasitic loss in the engine, it only reduces the losses required to spin up the dampner. It will show it's best gains when the engine speed is increasing at it's most rapid rate. It would show no gain at a steady engine speed (like climbing a hill). That's not my opinion, that's physics. Dyno charts would show the best gain in 1st, and essentially no gain in 5th. So called "back to back" dyno pulls that were performed in different gears would be totally useless at best and intentionally deceptive at worst. I would love to see back to back tests in 1st gear and in 5th gear, that would illustrate the point very well.
The AEM would show an increase net HP gain while the engine is accelerating and while the engine is operating at steady state.
You could always use both if you want, they are not exclusive to each other.
I have the AEM and believe in it but I would not be averse to using both.
Last edited by LSRCivic; Mar 11, 2004 at 10:12 PM.
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From: SoCal
Rep Power: 0 Originally posted by djmota
the difference is wieght on the crankshaft. The reduction of wieght at the crank will give you more gains then just underdriving the accesories.
the difference is wieght on the crankshaft. The reduction of wieght at the crank will give you more gains then just underdriving the accesories.
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From: Metro Detroit, Michigan
Rep Power: 0 Originally posted by sw388integra
and you guys still bought them...tisk-tisk!!!!
and you guys still bought them...tisk-tisk!!!!
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From: Gainesville, Ga.
Rep Power: 0 Originally posted by bobbyd
That is nothing new on these forums! These kids pay good money for pure crap all the time with NO proof of ponies first. Look at the KMS intake incedent. Don't be fooled people. If these companies were that great they would have no problem showing you dynos FIRST. Just because they have built fast cars in the past does not mean ever part they make is great.
That is nothing new on these forums! These kids pay good money for pure crap all the time with NO proof of ponies first. Look at the KMS intake incedent. Don't be fooled people. If these companies were that great they would have no problem showing you dynos FIRST. Just because they have built fast cars in the past does not mean ever part they make is great.
One of the best replies I have heard in a looong time!!! I was one of those burnt by KMS so I know first hand...How can someone develop a part for a car, say that it will x amount of horsepower and not even test it or dyno it???? I'll wait and see what happens with all these parts coming from DH before I fork out anymore cash. I could personally care less what they have done with previous B series engines...That has nothing to do with our cars..That dual groove pulley that they're selling is "supposed" to make 10whp..We'll see when someone dyno's....
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From: Metro Detroit, Michigan
Rep Power: 0 Sorry you got burned by KMS. I talked to them at Nopi two years ago and I was excited about them making 7th gen parts but not now. I want to see dyno proof now flow bench test that tell me it flows better. Slap that thing on a car and run it on the dyno!
Originally posted by bobbyd
Sorry you got burned by KMS. I talked to them at Nopi two years ago and I was excited about them making 7th gen parts but not now. I want to see dyno proof now flow bench test that tell me it flows better. [PHP]Slap that thing on a car and run it on the dyno![/PHP]
Sorry you got burned by KMS. I talked to them at Nopi two years ago and I was excited about them making 7th gen parts but not now. I want to see dyno proof now flow bench test that tell me it flows better. [PHP]Slap that thing on a car and run it on the dyno![/PHP]
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From: Maryland
Rep Power: 0 Why are people ******* AEM UnderDrive pulleys in other forums -- They say that they can ruin your engine or breakdown on you. I just bought some an dhaven't installed them yet ... now I am a little skeptical about it. How can they ruin your engine? Please help
My penis is just like all my posts, very very short
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From: SF Area
Rep Power: 348 with the Aem one are they bad on daily dirver ?
and futhermore will my AC be weaker then it is now?
and futhermore will my AC be weaker then it is now?
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From: Louisiana
Rep Power: 0 Ive had the AEM power pullies on my 02 civic for a year I have no problems and the pulley's gave me better throttle response and a little better pick up. I would say maybe 5 WHP. I have friends with the same mods on thier 7th gen civic with out the pullies and Im faster than them. Its a good mod but dont expect anything like 10-20 WHP.
My A/C works just as good in my car now as when i bought it.
My A/C works just as good in my car now as when i bought it.
Originally posted by Zachgeyer
with the Aem one are they bad on daily dirver ?
and futhermore will my AC be weaker then it is now?
with the Aem one are they bad on daily dirver ?
and futhermore will my AC be weaker then it is now?
I had the AEM's on my car for 19,000 miles with a pretty big I.C.E. system. I had no problems. I can't see any reason why there would be a reliability issue like with crank pullies. They are questionable because they remove the rubber dampner from the crankshaft, the AEM simply underdrives the Alternator & P/S by making those 2 pullies larger and leaving the crankshaft pulley/dampner alone. The A/C is unchanged. Also, the AEM kit includes the new belts required and installation instructions.
