HP conversion from time slip
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From: Valley Center KS
HP conversion from time slip There are a lot of calculators out there that convert your et/mph to HP. When I type in my time it says 190 to 205 HP depending on et or mph and which factors people are using (and 4150 lbs). So my question is, is this RWHP or flywheel HP.
I'm thinking its RWHP, cause there are too many variables for a calculator like this to get flywheel HP unless it makes some pretty big assumptions.
Assuming that this is RWHP, then my flywheel HP would be about 250 (20% drivetrain loss) which would probably be about right. I think originally it was rated at 235HP in an 87 Z28. I have headers, airfoil, CAI, and AFPR for mods too it, so for an old engine that is past its prime (who knows how many miles are on it so this also seems reasonable. Next CCC, I'll be sure to put some 92 octane in it rather than the 87 that I have been running. See if that helps out.
I'm thinking its RWHP, cause there are too many variables for a calculator like this to get flywheel HP unless it makes some pretty big assumptions.
Assuming that this is RWHP, then my flywheel HP would be about 250 (20% drivetrain loss) which would probably be about right. I think originally it was rated at 235HP in an 87 Z28. I have headers, airfoil, CAI, and AFPR for mods too it, so for an old engine that is past its prime (who knows how many miles are on it so this also seems reasonable. Next CCC, I'll be sure to put some 92 octane in it rather than the 87 that I have been running. See if that helps out.
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From: Bellingham/Edmonds, WA
http://robrobinette.com/et.htm is the one I use a lot just to get an idea, it's a pretty handy tool. I just use it to guess and check for both wheel and flywheel hp. The ones that estimate based on trap speed I think are more accurate though.
15.9 huh? That's not too bad at all!
15.9 huh? That's not too bad at all!
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From: Valley Center KS
I was expecting high 14s....not high 15s though.
I did pick up a half a second by shifting myself. For some reason if I just put it in OD or D and let it shifts, it only holds it until ~4100 RPMs. I have a ratchet shifter, so I can bang the next gear at 5k pretty consitantly....though a shift light would help if I race it more....but next year its going to be torn apart undergoing a full frame off restoration.
I did pick up a half a second by shifting myself. For some reason if I just put it in OD or D and let it shifts, it only holds it until ~4100 RPMs. I have a ratchet shifter, so I can bang the next gear at 5k pretty consitantly....though a shift light would help if I race it more....but next year its going to be torn apart undergoing a full frame off restoration.
You might be supprised what a little more timing might do (when using Premium fuel)....You could be easily leaving 2 or 3 tenths on the table(maybe more)...How much total advance do you have in there now? and a scanner would help tell you if your seeing knock retard already...
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Originally Posted by jimbob
You might be supprised what a little more timing might do (when using Premium fuel)....You could be easily leaving 2 or 3 tenths on the table(maybe more)...How much total advance do you have in there now? and a scanner would help tell you if your seeing knock retard already...
I was planning on doing some tuning after I got eliminated, but didn't want to stick around that long.
8*?! Damn, I thought I was low at 13*.....more timing Derek, MORE! PM me with your email address & I'll send you Greg P's Excel file that I use. You can calculate HP, shift points, all sorts of stuff with it. But you need to know your tranny gear ratios, tire size & weight.
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From: Valley Center KS
I filled up with some premium yesterday, and then dialed in some more timing. Up to about 12* initial now. I was at 14*, but had some pinging so I backed it back down. I can definatly tell that it picked up some low end torque, and I'm sure it helped up top as well.
I guess we'll see if it helps next time I go to the track.
I guess we'll see if it helps next time I go to the track.
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Originally Posted by Ackattack1
I filled up with some premium yesterday, and then dialed in some more timing. Up to about 12* initial now. I was at 14*, but had some pinging so I backed it back down. I can definatly tell that it picked up some low end torque, and I'm sure it helped up top as well.
I guess we'll see if it helps next time I go to the track.
I guess we'll see if it helps next time I go to the track.
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From: Yelm, Wa
air foil sucks.
Suggestion cut the bottom of the box out if its TPI
I am working on my 87 Iroc with a 355 (bored it over last winter) HSR
if you need any engine stuff let me know I have alot of the stock stuff running around. The only thing you cant have is the intake system. That is my brother in laws after he helps me finish up my engine.
Plus I have alot of interior stuff too.
Suggestion cut the bottom of the box out if its TPI
I am working on my 87 Iroc with a 355 (bored it over last winter) HSR
if you need any engine stuff let me know I have alot of the stock stuff running around. The only thing you cant have is the intake system. That is my brother in laws after he helps me finish up my engine.
Plus I have alot of interior stuff too.
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It is in a truck, so I doubt he is using the airbox.
IMHO, there is no reason to play with the base timing. If you want to play with it get a custom chip and do it there. I would never think of adding any base timing to my 88 TA and we have nearly identical TPI systems.
IMHO, there is no reason to play with the base timing. If you want to play with it get a custom chip and do it there. I would never think of adding any base timing to my 88 TA and we have nearly identical TPI systems.
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From: Lynnwood, WA (North of Seattle)
Originally Posted by Amorget
It is in a truck, so I doubt he is using the airbox.
IMHO, there is no reason to play with the base timing. If you want to play with it get a custom chip and do it there. I would never think of adding any base timing to my 88 TA and we have nearly identical TPI systems.
IMHO, there is no reason to play with the base timing. If you want to play with it get a custom chip and do it there. I would never think of adding any base timing to my 88 TA and we have nearly identical TPI systems.
