1st 2.5L Inlinepro Stroker Kit
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From: Grand Prairrie
Originally Posted by gernby,Oct 30 2004, 07:46 AM
In the 1st dyno plot, they plotted the speed along the X axis, and didn't use the same gearing. This gives the appearance that the new motor is making a LOT more power than it really is by shifting the graph to the left. This isn't a very fair representation.
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From: Wylie, TX
Originally Posted by brogers,Oct 30 2004, 11:03 AM
Are you sure they are using different gears? ... I would assume he is not revving the stroked motor to the stock redline because of the large increase in piston speeds.
The A/F does look like it could be leaned out quite a bit, though.
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It may not be a change in gearing, but it really is hard to tell. Everything looks shifted down about 10 MPH to me, including the VTEC engagement. It looks like my dyno plots when I compare my 4.77 runs against my 4.10 runs using speed as the x-axis.
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From: NOVA/Rye,NY/Tempe AZ
sorry about the graphs i thoguht i got the ones with rom on the x axis sorry we made just about twenty passes wiht the motor. The engine is still on the vafc wehn we were on the dyno we tryed the 440cc injectors, then we went to the 550cc then we finally ended up with the 575cc in the end they seem to work the best. we could lean it out more but when we did it lost power so it likes to run rich. the air/fuel needs to dialed down more but we still might use the e manage. the vtec is coming on 4500rpms and we are cutting the motor off at 8k because it doesnt make any power after 8k so we were cutting it off after 8k, it revs up to nine kinda pointless though. the gearing in the car is still stock. The cars only dyno notable mods are the bottom end,clutch,flywheel,injectors,vafc,intake,exhuast. Ill get a video up of the car on the streets and the dynos with rpm on the x axis.
-Matt
-Matt
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Originally Posted by gernby,Oct 25 2004, 03:01 PM
"They" didn't plot anything for me. The plots I posted are the ones that I put together using the DynoJet Runviewer. The torque curve is no more informative than the HP curve, since there is a direct mathematical correlation between them (HP = torque * RPM / 5200). Note: I realize that the 5200 is not quite exact, but I always forget the last 2 digits.
The reason why the fuel tuning doesn't make that much of a difference is because the '02 OEM ECU really is pretty damn good. There just isn't that much to be gained from tuning (fuel or timing) on a nearly stock motor. That said, I think an additional 6 HP from 6300 to redline is pretty damn good considering that is above what I could get with the VAFC. I suspect that the OEM ECU is giving more agressive timing as a result of more consistant AFRs. For example, with the VAFC, I was probably getting some occasional detonation when the AFR went above 14:1 after VTEC. This probably caused the ECU to back off timing across the whole range.
I can't think of any "degree" that your statement about 13.5 vs 10 not making a difference in power. An AFR of 10 would cause the plugs to foul out very quickly, and no amount of ignition timing would compensate for it.
I considered adding timing control into my fuel controller, but really didn't feal comfortable with taking that away from the OEM ECU. Timing is something that I think is dangerous to play with, unless it is to retard timing for safety purposes (FI, increased compression ratio, etc.).
The reason why the fuel tuning doesn't make that much of a difference is because the '02 OEM ECU really is pretty damn good. There just isn't that much to be gained from tuning (fuel or timing) on a nearly stock motor. That said, I think an additional 6 HP from 6300 to redline is pretty damn good considering that is above what I could get with the VAFC. I suspect that the OEM ECU is giving more agressive timing as a result of more consistant AFRs. For example, with the VAFC, I was probably getting some occasional detonation when the AFR went above 14:1 after VTEC. This probably caused the ECU to back off timing across the whole range.
I can't think of any "degree" that your statement about 13.5 vs 10 not making a difference in power. An AFR of 10 would cause the plugs to foul out very quickly, and no amount of ignition timing would compensate for it.
I considered adding timing control into my fuel controller, but really didn't feal comfortable with taking that away from the OEM ECU. Timing is something that I think is dangerous to play with, unless it is to retard timing for safety purposes (FI, increased compression ratio, etc.).
ignition timing is where you will find all the power, not in a/f... that is all I'm trying to say...
and thanks, I understand that hp is a calculated from torque... that's why any tuner will tune for torque... at least you could have gotten the equation right.
I'm still amazed you would spend the $$$ on all that and NOT tune it on a stand alone... People are showing consistent 8-10ft/lb gains across the entire rpm range with AEM EMS's; with peak gains over 20ft/lbs... on stock engines...