Hp Loss With Ho Alt Upgrade?

[Kranny]

I was talking with my auto's teacher about this. and he whips out this huge ass formula and asks me the HP of my car, how many amps the alt will make etc..

for me, my 94 corolla. Around 95hp (stock, baseline model), and it ended up being something like 85hp after a 160amp upgrade.

so i want to know the formula that shows it so i can do some calculations later on.

Thanks

[CustomCarputers]

That's the thing about teachers, most have not worked as techs for long.

People come up with these "huge ass" formulas which don't mean crap in the real world.

[Kranny]

well i trust him since he has a master technician degree and is certified in every field of automotive work. I saw his certificate and it had like 10+ things on there that he passed

and he went to wyotech too for training

Edited April 25, 2008 by Krannyman92

[ChevyBoy]

yet he can still be a dumbass. i wont believe everything someone from harvard said or did.

[jack]

yes it will affect performance but only when it is needed. that 160 is a peak...it probably cruises along at 75 amps until it engages during massive power draw. i have a 300amp on a 50 hp(rated when new) 3cyl. now has alot more wear. during normal driving i dont notice the differace from before i added it but it deffinatly will make the car surge when i am taking care of business!

[Kranny]

i have a 300amp on a 50 hp(rated when new) 3cyl. now has alot more wear.

what the hell kind of car uses 3 cyl?

found the exact formula he was talking about

Amps x Volts = Watts

Watts / 745.7 (one HP) = Electrical HP Produced by the Alternator

HP x 15% Efficiency Loss = HP Loss

HP + HP Loss = Total HP Used

i used 160 amps and 14.4 volts

160 x 14.4 = 2,304w

2,304w / 745.7 = ~3.08

3.08 x .15 = .463

3.08 + .463 = 3.54hp

so i lose 3.5hp spinning that 160 amp alternator apparently

Edited April 25, 2008 by Krannyman92

[mbdblue]

what the hell kind of car uses 3 cyl?

geo metro.....dont know if thats what he has but they are....and if your only losng 3-4 horses, your not gonna be able to tell the difference anyway.

Edited April 25, 2008 by mbdblue

[Kranny]

lol, thats pretty funny imo. so im pretty much safe with getting a HO alternator.

[ChevyBoy]

yes he has a geo

[qu1cks1lver56]

youre not gonna see that much hp loss.

and if it is 10, youre really not gonna be able to tell, just upgrade to a k&n cold air intake and filter and a better exhaust and you'll cancel it out and might make more power