C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

'85 mod question

Old May 11, 2006 | 08:47 AM
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I was at a Corvette parts store trying to get the stuff to finish my broken harmonic balancer "smog" project (long story). Anyway ...the clerk tells me that I should get a smaller crankshaft pulley while I had the car torn down, that it would add 11-12 HP and was a typical upgrade. I almost bit...but thought better of it. Anyone hear of this? It is about a $70 part plus a new belt.
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Old May 11, 2006 | 09:59 AM
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the underdrive pulley mods will give about a tenth on average, so they werent lying
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Old May 11, 2006 | 10:18 AM
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I have the TPIS 2 piece system, which is made by March. One crank pulley, the other the alt. pulley. I suffer no loss of voltage at idle, which some forum members claim after the install. It does not come with a belt, but they tell you belt part #s from different manufacturers
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Old May 11, 2006 | 10:23 AM
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I'll bet you have an amperage loss.

RACE ON!!!
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Old May 11, 2006 | 10:36 AM
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E=I X R. Amperage is volume of electrons, voltage is pressure of electrons. So I have a lower volume of electrons? I have a power loss but not a force loss? I don't know where this loss would manifest itself. Interersting.
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Old May 11, 2006 | 11:28 AM
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Originally Posted by jmrl98
I don't know where this loss would manifest itself. Interersting.
In less alternator output.

Volts X Amps = Watts. You certainly can't have an equal amount of power (watts) output with a lesser amount of input. You say the volts haven't dropped, so it must be the amps that have. If you do have an equal amount of power output, with a lesser amount of input, keep developing. You are well on you way to a perpetual motion machine.

RACE ON!!!
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Old May 11, 2006 | 11:40 AM
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Thanks.
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Old May 11, 2006 | 01:37 PM
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i have the three pulley system, no amperage loss, but also didn't notice an gain either.
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Old May 11, 2006 | 04:04 PM
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Originally Posted by 86VX1
i have the three pulley system, no amperage loss, but also didn't notice an gain either.
How did you measure amperage loss?

Anyhow, the electronics requires a certain amount of power from the alternator. If you reduce the power into the alternator, it'll have to charge more often (and sap motor hp more often) to maintain that power. Net gain with pulleys on the alternator is zero. Now, if you have a cutoff switch to the alternator and use it during drag runs, you might pick up something there. I've never seen anyone on here mention doing that though.

How much hp does it take to turn a powersteering pump when the car isn't turning? or an a/c compressor thats not engaged?

You'll pick up some lost hp by turning the waterpump slower, but that's probably the last accessory you want to slow down.

Last edited by CentralCoaster; May 11, 2006 at 04:09 PM.
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Old May 11, 2006 | 05:01 PM
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Originally Posted by CFI-EFI
In less alternator output.

Volts X Amps = Watts. You certainly can't have an equal amount of power (watts) output with a lesser amount of input. You say the volts haven't dropped, so it must be the amps that have. If you do have an equal amount of power output, with a lesser amount of input, keep developing. You are well on you way to a perpetual motion machine.

RACE ON!!!

i had an idea for perpetual motion, but i couldn't get a patent. they refused to look at the working model.


i stand on a crate and drink beer while peeing on a paddle wheel attached to a generator. i think they turned me down because of the obvious accumulating drag on my bank account.

it's a small world for us geniuses.
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