Ok, before the flames... Does anybody have ANY proof whatsoever?
I mean like a dyno run with a bone stock lude vs. a dyno run with a bone stock lude with pullies.
My step-dad is an auto technician and I told him I was going to get pullies, he just laughed and me. We got to talking about how they work and why they work (or dont work)
Everybody says they work because they reduce parasitic hp loss from turning the accessories.
There is Some truth to this.
The p/s pump effort only increases when you are turning, otherwise, the pulley basically freewheels in the housing, not pumping anything. Yes, there is some effort required to turn the pulley in the fluid. The cheaper and better alternative would be to simply remove the p/s pump when your at the track.
The alternator is a different story. Effort to turn the pulley is dependant on electrical load. I dont race with my brights on, or the defroster, or the radio... Do you? Probabally not. So your going to have minamal effort to turn the pulley anyway, but effort (and hp loss) none the less... Here is the secret, the alternator can be disconnected via a switch and a relay when you roll up to the line. Domestic guys have been doing this for years, its not even really a secret. (Step-dad used to do this on his 69 Roadrunner when he went to the strip back in the 70's) Its juat called common sense.
Why pay $150 for something that can be done for less then $7...
Because *most* (not all) people who buy imports to be in the "in" crowd (that is if mommy and daddy dont buy it for them) cant see past the hype. "Hey look at that (insert part here), Its crome and anodized, it must work... Plus it comes with stickers!"
I dont car what your "butt dyno" tells you... Ever hear of the placibo effect? I want hard evidence. Actual dyno numbers. Not runs at a track, those are way to inconsistent to prove anything.
I expect to get flamed from the people that have bought pullies, I would be mad too if I spent a pile of money for almost no gain.
correct me if im wrong, i havent researched em to much cause im not planin on getting them (at least for a while) but arent they a different size (smaller) to? hence underdrive? because they under drive the alternator, powersteering etc. kind of like 15 in wheel compared to a 17 in wheel?
Originally posted by illusion yeah.. i expect to take off the power steering belt when i go to the track. i figure thats the best way.
I did that once. I gained JACK in the 1/4 mile. Not even a tenth. Actually, to tell you the truth, when I put it back on, I ran faster. The only thing I accomplished by taking off the p/s belt was making it a PIA to turn at the end of the strip, and now the p/s belt/pulley squeeks at idle. As for the alternator, I'd just use the method on disconnecting it, if I knew how, care to enlighten us Jason?
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Gone, but not forgotten...rest in peace Jon.
AS most people are aware, I have written a book on the prelude. In the book I tested just about every bolt on performance part you can buy. One of the items I tested was the AEM Tru Power Pullies. These were tested on a stock Prelude Vtec with about 78K miles on the Odo. Basline run on the car netted 167.2hp at 5650rpm, and 142.6ftlbs tq. This was done on a dynojet chassis dyno, temp was 78degrees, with a relative humidity of 67%. The runs were performed in 4th gear all the way up to 7100rpm. With the pullies in place, the car put down a pretty respectable 170.1hp at 5500 rpm and 144.5ft lbs. This was average gain with a peak increase of roughly 6hp in the top end. I am pulling this right off the dyno sheet for that test. So, believe me when I say that these mods do work. We also tested them against the unorthodox pullies and the gain was pretty much the same.
um.. people in civic si's have taken off the power steering belt and gained 6whp. so i dont know how "ineffective" it is. we'll see what times i get friday.
Originally posted by Dr. James AS most people are aware, I have written a book on the prelude. In the book I tested just about every bolt on performance part you can buy. One of the items I tested was the AEM Tru Power Pullies. These were tested on a stock Prelude Vtec with about 78K miles on the Odo. Basline run on the car netted 167.2hp at 5650rpm, and 142.6ftlbs tq. This was done on a dynojet chassis dyno, temp was 78degrees, with a relative humidity of 67%. The runs were performed in 4th gear all the way up to 7100rpm. With the pullies in place, the car put down a pretty respectable 170.1hp at 5500 rpm and 144.5ft lbs. This was average gain with a peak increase of roughly 6hp in the top end. I am pulling this right off the dyno sheet for that test. So, believe me when I say that these mods do work. We also tested them against the unorthodox pullies and the gain was pretty much the same.
Now this is the proof im talking about...
Did you ever do a dyno run with the alternator disconnected altogeather? I would almost bet you gain even more hp then with the pullies... And when you were done "racing" you could flip the switch back on and not have to worry about poor charging performance...
Originally posted by Dr. James AS most people are aware, I have written a book on the prelude. In the book I tested just about every bolt on performance part you can buy. One of the items I tested was the AEM Tru Power Pullies. These were tested on a stock Prelude Vtec with about 78K miles on the Odo. Basline run on the car netted 167.2hp at 5650rpm, and 142.6ftlbs tq. This was done on a dynojet chassis dyno, temp was 78degrees, with a relative humidity of 67%. The runs were performed in 4th gear all the way up to 7100rpm. With the pullies in place, the car put down a pretty respectable 170.1hp at 5500 rpm and 144.5ft lbs. This was average gain with a peak increase of roughly 6hp in the top end. I am pulling this right off the dyno sheet for that test. So, believe me when I say that these mods do work. We also tested them against the unorthodox pullies and the gain was pretty much the same.
>>>>>>>>>>Awsome, you wrote a book on the lude? I'd be interested in reading it. Let me know...
Dr. James: is the book out yet? I'd be interested in a copy
Absolut: well I have no proof or anything but I don't understand how disconnecting the alternator would give any gain? I mean even if it doesn't charge the battery, doesn't the mecanism inside the alternator still rotates? same thing for the P/S pully, even if you're not turning to pully still pumps the fluid, those pullies aren't like the A/C one which is clutch activated, when you don't use it only the pully turns and when you use it the pully and the mecanism in the compressor too and it pumps the A/C fluid
that's how I see it should work but if not how can you gain power by just disconnecting the alternator?
Originally posted by Forbidden Dr. James: is the book out yet? I'd be interested in a copy
Absolut: well I have no proof or anything but I don't understand how disconnecting the alternator would give any gain? I mean even if it doesn't charge the battery, doesn't the mecanism inside the alternator still rotates? same thing for the P/S pully, even if you're not turning to pully still pumps the fluid, those pullies aren't like the A/C one which is clutch activated, when you don't use it only the pully turns and when you use it the pully and the mecanism in the compressor too and it pumps the A/C fluid
that's how I see it should work but if not how can you gain power by just disconnecting the alternator?
When the alt or ps is under load thats when it draws the most power.. just because its spining doesn't mean it is drawing power.
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"A Honda with Torque, thats an oxymoron" No, its called a Prelude.. Understand! "Yes SR..V"
well still... cause the alternator is making electricity it's gonna be harder to make it spin? doesn't make sense to me... it'll still be making that electricity but it just won't be able to send it somewhere...
Originally posted by Forbidden well still... cause the alternator is making electricity it's gonna be harder to make it spin? doesn't make sense to me... it'll still be making that electricity but it just won't be able to send it somewhere...
When the alt and PS are not under load think of like the wheeling A/C (when the A/C is off) its spining but its not drawing power.
Yes the alternator is making electricity but very little. Haven't you notice when you turn on all your lights and accessories the idle drops, we'll thats because there is more load on your alternator and therefore, it is more of a drag on your engine. So if your going to race make sure your 'system', fog lights ...... are all off.
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"A Honda with Torque, thats an oxymoron" No, its called a Prelude.. Understand! "Yes SR..V"
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