Want feedback on this dyno run
#18
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A little fat, but nothing that I would expect to be robbing you of those 30 more hp you were expecting. I would guess there was some roll off of boost, but yo usay that isn't the case.
However, I know many people in here, and when I went with my buddy to dyno, that the boost made on the street, is not always the boost made on the dyno. In my friends case he made 15 dead on on the street. On the dyno it would not hold more than 13 to redline. Maybe a dyno load issue??
So I would bet that might be why you are seeing less hp than expected. 1-2 more psi would give you 15-25 more hp you thought should have been there; add that to the 15hp for temps and fan and you are right there
However, I know many people in here, and when I went with my buddy to dyno, that the boost made on the street, is not always the boost made on the dyno. In my friends case he made 15 dead on on the street. On the dyno it would not hold more than 13 to redline. Maybe a dyno load issue??
So I would bet that might be why you are seeing less hp than expected. 1-2 more psi would give you 15-25 more hp you thought should have been there; add that to the 15hp for temps and fan and you are right there
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#21
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To clarify, there is no AFM, a 3" j pipe goes straight into the stock airbox. There some pictures in this thread.
https://rennlist.com/forums/showthre...t=stock+airbox
and some discussion here.
https://rennlist.com/forums/showthre...t=stock+airbox
Todd, your right, it very well could be a boost issue. Again, if I had logs in parrallel to the runs I could say for sure.
https://rennlist.com/forums/showthre...t=stock+airbox
and some discussion here.
https://rennlist.com/forums/showthre...t=stock+airbox
Todd, your right, it very well could be a boost issue. Again, if I had logs in parrallel to the runs I could say for sure.
#22
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Originally posted by B951S
Tom
That raises a good point. One thing I noticed was that the PLX wideband in the car read richer than the dyno by a little. Again, no datalogging during pulls so its hard to say by how much but I will take it back and this time data log when making pulls. I want to upgrade the intercooler, and intake first.
One question, should I be aiming for a 12.5 as soon as max boost hits or taper from a leaner AFR like 13.5 at max boost low rpm to 12.5 at max boost max rpm.
Tom
That raises a good point. One thing I noticed was that the PLX wideband in the car read richer than the dyno by a little. Again, no datalogging during pulls so its hard to say by how much but I will take it back and this time data log when making pulls. I want to upgrade the intercooler, and intake first.
One question, should I be aiming for a 12.5 as soon as max boost hits or taper from a leaner AFR like 13.5 at max boost low rpm to 12.5 at max boost max rpm.
For A/F ratios I shoot for 12.5:1 by about 5psi then after about 5000rpm I don't worry if it goes up to 13:1 because there is a lot less noise in the engine on the knock sensor and from what I have read max power is around 13:1 all the extra fuel is for cooling purposes. Now if you are going to be using the car on the track you might want to tune to the rich side because you are stressing the engine for longer periods of time and the loss in power is not a whole lot.
#23
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Yes, I tune on on the street using data logging from a WB and driving the car usually WOT in 3rd for a WOT pull so the speeds dont get crazy. I understand your point... So does that mean there is a an offset that you should build into dyno tuning on a hot day. I mean tuning 12.5 on a dyno in sweltering heat with a little fan is gonna have to satify the neeeds of the motor on a cooler day with proper front air cooling. THe link has a simple inlet air temp offset where you can specify how much fuel the computer adds accross the board for cooler IAT temps. As far as I understand this IAT correction should account for some of the differences. Link alsways told me never to put the IAT after the intercooler outlet as the transients and dynamics in temperature changes were too much for real time correction, I guess if it works for you it can't be all bad.
Anyway, I am pretty convinced the stock cold air snorkel will start restricting the motor quite a bit when you are trying to lay down over 300 rwhp. It will be interested so see what it makes once I take off.
Thanks
Anyway, I am pretty convinced the stock cold air snorkel will start restricting the motor quite a bit when you are trying to lay down over 300 rwhp. It will be interested so see what it makes once I take off.
Thanks
#24
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FWIW I recently tuned an 89 car with a fresh valve job, Fabspeed test pipe, LBE and custom chips and it made 299 rwhp with the OE turbo peaking at 1 bar. He also had the AFM but with a cone filter attached. His A/F was around 10:1 and when I leaned out the curve it lost a little power as a result. This is pretty consistant with my experience tuning these cars. They like to be fat.
The chip set we were working off of were APE stage 2. We were using a Superflow dyno. You on a Dynojet?
The chip set we were working off of were APE stage 2. We were using a Superflow dyno. You on a Dynojet?
#25
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"FWIW I recently tuned an 89 car with a fresh valve job, Fabspeed test pipe, LBE and custom chips and it made 299 rwhp with the OE turbo peaking at 1 bar. He also had the AFM but with a cone filter attached."
With APE chips?????? and only 15psi?????
With APE chips?????? and only 15psi?????
#26
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Originally posted by toddk911
Also, I thought you couldn't run more than 15 psi with Vitesse on pump gas??
Also, I thought you couldn't run more than 15 psi with Vitesse on pump gas??
#27
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Your torque curve looks a lot like mine. I bet your car pulls very hard. I've driven mine back to back with other cars making more peak HP, and the flat torque makes for a harder pulling street car. I trust your graph was adjusted for the heat. Otherwise, you are making more than the chart shows (on an adjusted/comparable basis). Keep tweeking (sans snorkel) and I see 330 in your future.
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#29
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Yes I was kicking myself after, I should have taken the cover off for a comparison, next time for sure.
FYI, I did a few street runs in 3rd, WOT from low down to red line while datalogging. Here is the boost curve for 2 runs back to back. I see I am loosing a psi or so, I guess there is some improvement to be had here that would help.
FYI, I did a few street runs in 3rd, WOT from low down to red line while datalogging. Here is the boost curve for 2 runs back to back. I see I am loosing a psi or so, I guess there is some improvement to be had here that would help.