alternator parasitic loss
08-27-2003, 01:01 AM
#1
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alternator parasitic loss
Just wondering since with underdrive pulleys the only 2 things that are always in use that it would be slowing down are the power steering pump and the alternator right? and your only slowing them down like 25 % which is worth what like 5hp, well if you disconnect the alternator totally instead of using "power" pulleys how much power would that be worth for a run at the track I mean I can reach right in there and unplug it easy, if its worth a few pony's why not?
08-27-2003, 12:04 PM
#2
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The ws6.com dyno test of the Hypertech U/D pulley netted 0.7rwHP, peak. Average HP gain was 4.4rw. There is not a lot to be gained. Guys that pull the belt claim 1 to 2 tenths ET improvement. But the last thing you want to do on an EFI engine is deprive the computer and the fuel pump of power.
08-27-2003, 12:43 PM
#3
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The belt mod is worth a .1 at the track as fred said. I have never had a issue with computer or fuel delivery without the alt hooked up, but i will never run more than 2x without recharging the battery either.
08-27-2003, 01:49 PM
#4
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yeah im not pulling the belt I was going to figure a way to engage and disengage the alternator using a switch and splicing wire, hell 1 tenth is like ~10hp so say the alt is half that so 5 hp for practically no cost, friend gave me the idea and I figure it would work.
08-27-2003, 01:56 PM
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wow, anyone else remember that thread???
A couple years ago there was a post on doing the wire trick, and it got hunderds of responses. I think it was officially the longest thread in LT1 tech history.
Title was something like "You want 100hp for free" or something like that.
A couple years ago there was a post on doing the wire trick, and it got hunderds of responses. I think it was officially the longest thread in LT1 tech history.
Title was something like "You want 100hp for free" or something like that.
08-27-2003, 08:14 PM
#6
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there was someone who did this before? I dont see why its not done more if it is worth atleast 5hp and tq I mean its pretty easy to splice wire and cheap, then all you need is a switch and a way to route the wire, less than the cost of underdrive pulleys and you can decide when to use it like not when your cranking up the stereo and much more worth it....
08-27-2003, 08:29 PM
#7
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yeah im not pulling the belt I was going to figure a way to engage and disengage the alternator using a switch and splicing wire, hell 1 tenth is like ~10hp so say the alt is half that so 5 hp for practically no cost, friend gave me the idea and I figure it would work.
I am working on it. But I wont be using an old nasty switch. Electronic switch is moh like it for me.
I did an electronic fan mod swith totally automatic and it works just fine. This Alternator mod will use a high power mosfets in parallel to disconect the alternator or.... if I am right there is a conection that deactivates the Alternator.. I havent studied it yet... but I think its a great idea for short runs...
Marvin
08-28-2003, 01:42 AM
#8
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Originally posted by atljar
wow, anyone else remember that thread???
A couple years ago there was a post on doing the wire trick, and it got hunderds of responses. I think it was officially the longest thread in LT1 tech history.
Title was something like "You want 100hp for free" or something like that.
wow, anyone else remember that thread???
A couple years ago there was a post on doing the wire trick, and it got hunderds of responses. I think it was officially the longest thread in LT1 tech history.
Title was something like "You want 100hp for free" or something like that.
Wasnt the kid young too? I remember Brent had to close it b/c it was so long...Those were the days...
09-09-2003, 10:39 PM
#11
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Ok for the guys who followed up this thread I got one small update.
I got some free time now and I will begin doing research on this Mod. The first thing that crossed my mind is...
If I electronically disconect the Alternator when the Car is at WOT the Voltage will automatically drop to the Batterys 12 Volt with a Healthy Battery. Maybe much more with a weak battery
So its obvious I will need a voltage step-up box to increase it back to 13.8 as if the alternator was still chargin. Sounds like a lot of trouble to begin with since that electronic part would have to handle a massive amount of amps unless I only use it to feed the Ignition parts in wich case is more manageable.
I find this first sted necesarry because I dont want to loose any horses from the voltage drop and somehow weakened ignition. I think someone already sells a V step up box but mine has to either switch on at wot or be on at all times... like a Voltage regulator. I havent decided yet. I think its very possible to electronically swith the alternator off and I will look into it in the next few days. even if its only like 5 horse power to gain I am willing to look into since Electronics is my hobby and I have about two weeks of free time right now. Its not my vacation... I am passin a kidney stone (first time ever) and it hurts like a B.i.t.c.h.
I am under medication though and too much time in my hands right now.
I will update my post every now and then. If I make it work I dont plan to sell anything.... I will probably just share my diagrams if I make it simple enough.
Just to let you know guys..
Marvin -out
I got some free time now and I will begin doing research on this Mod. The first thing that crossed my mind is...
If I electronically disconect the Alternator when the Car is at WOT the Voltage will automatically drop to the Batterys 12 Volt with a Healthy Battery. Maybe much more with a weak battery
So its obvious I will need a voltage step-up box to increase it back to 13.8 as if the alternator was still chargin. Sounds like a lot of trouble to begin with since that electronic part would have to handle a massive amount of amps unless I only use it to feed the Ignition parts in wich case is more manageable.
I find this first sted necesarry because I dont want to loose any horses from the voltage drop and somehow weakened ignition. I think someone already sells a V step up box but mine has to either switch on at wot or be on at all times... like a Voltage regulator. I havent decided yet. I think its very possible to electronically swith the alternator off and I will look into it in the next few days. even if its only like 5 horse power to gain I am willing to look into since Electronics is my hobby and I have about two weeks of free time right now. Its not my vacation... I am passin a kidney stone (first time ever) and it hurts like a B.i.t.c.h.
I am under medication though and too much time in my hands right now.
I will update my post every now and then. If I make it work I dont plan to sell anything.... I will probably just share my diagrams if I make it simple enough.
Just to let you know guys..
Marvin -out
09-11-2003, 04:42 AM
#14
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Before you get too carried away with this, look at it from a BEST case scenerio and do some number crunching. Convert like 130 amps at 12v into HP and see what you get. I think you'll find that it's not going to be worth it.
In fact, you need to consider the flip side as well. There are products out there (like the Voltblaster) which actually INCREASE voltage to all the components in the car which actually makes the alternator work harder and thus draw more hp from the engine. These products claim an INCREASE in overall performance because of the higher voltage to the ignition setup, stuff like that. I'm not sure if the claims are true or not. I do know, however, that these products really help fuel pressure if you have fuel pressure problems (DC pump spins faster on higher voltage). So, don't forget about what "could" happen if voltage ends up being reduced at WOT.
In fact, you need to consider the flip side as well. There are products out there (like the Voltblaster) which actually INCREASE voltage to all the components in the car which actually makes the alternator work harder and thus draw more hp from the engine. These products claim an INCREASE in overall performance because of the higher voltage to the ignition setup, stuff like that. I'm not sure if the claims are true or not. I do know, however, that these products really help fuel pressure if you have fuel pressure problems (DC pump spins faster on higher voltage). So, don't forget about what "could" happen if voltage ends up being reduced at WOT.
Last edited by Brent94Z; 09-11-2003 at 04:46 AM.
09-11-2003, 05:54 AM
#15
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JMO and sort of a follow up on what injuneer said....
One of the first mods people do to a Buick GN is hot wire the fuel pump because it doesn't get enough voltage from the stock harness. What some people (like the FBI ) found was that at high RPM the motor would go lean and kill itself. If they are worried enough about voltage to the pump that vendors sell a (quite popular) hot wire kit for it, thats enough to tell me I have no interest in reducing the voltage going to the pump on my car
One of the first mods people do to a Buick GN is hot wire the fuel pump because it doesn't get enough voltage from the stock harness. What some people (like the FBI
) found was that at high RPM the motor would go lean and kill itself. If they are worried enough about voltage to the pump that vendors sell a (quite popular) hot wire kit for it, thats enough to tell me I have no interest in reducing the voltage going to the pump on my car