Holy Crap, did anyone notice Iron Lung's 99 5spd dyno: 191hp and 205tq
08-16-2002 | 11:10 AM
#41
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Posts: n/a
Comparing to my dyno, his car makes about the same torque at low (2500) rpms but has a larger 3300 rpm peak with very little drop thereafter. It pretty much plateaus between 3300 and 4500 rpm and has a larger 4500 rpm peak. He also seems to have a less severe torque dropoff (fatter torque curve) past 5000 rpms. Definitely is stronger than my motor.
Originally posted by Iron Lung
I just got back from the track and ran a 14.55 @ 96.14 with a 2.3 60' NA. I only did one NA because I kept lining up with a black Firebird and I just had to juice it. Anyways the temp was around 88 F and humidity was around 70%. My best run with nitrous did not please me because its still surging on and off. It was a 14.20 @ 101 mph. So am I putting out less than what the dyno says?
I just got back from the track and ran a 14.55 @ 96.14 with a 2.3 60' NA. I only did one NA because I kept lining up with a black Firebird and I just had to juice it. Anyways the temp was around 88 F and humidity was around 70%. My best run with nitrous did not please me because its still surging on and off. It was a 14.20 @ 101 mph. So am I putting out less than what the dyno says?
08-16-2002 | 01:43 PM
#42
Originally posted by Keven97SE
Looking at your n/a air/fuel chart, your car looks to be running perfect. The A/F starts off a little leaner (~13.5:1) at lower rpms but then gradually richens to ~12:1 at higher rpms. Looks good. However, your nitrous A/F could use some work at ~4600 rpm. Look at the rich A/F at that rpm (~10.5:1) and corresponding torque dip at the same rpm. You're so rich at that rpm that you have a torque dip there. There is nothing mechanical (cams, intake manifold, etc) that would explain that feature. If you could tune the A/F to around 11.5:1 from 4300-on (to match what you have ~5500 rpm), I think you'd see that torque dip go away and have more torque between ~4500 and 5300 rpms.
Looking at your n/a air/fuel chart, your car looks to be running perfect. The A/F starts off a little leaner (~13.5:1) at lower rpms but then gradually richens to ~12:1 at higher rpms. Looks good. However, your nitrous A/F could use some work at ~4600 rpm. Look at the rich A/F at that rpm (~10.5:1) and corresponding torque dip at the same rpm. You're so rich at that rpm that you have a torque dip there. There is nothing mechanical (cams, intake manifold, etc) that would explain that feature. If you could tune the A/F to around 11.5:1 from 4300-on (to match what you have ~5500 rpm), I think you'd see that torque dip go away and have more torque between ~4500 and 5300 rpms.
08-16-2002 | 02:24 PM
#43
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Posts: n/a
I think anywhere from 12:1 to 13:1 is a good target A/F ratio for mid-ro-higher rpms, even with nitrous. Stoichiometric is 14.7:1, so you're still fairly rich/safe when you're in the 12-13:1 range. It's obvious from your dyno+A/F plot that once you start getting down to the 10.5:1 range, the car is not making the torque/power it does when it runs more like 12:1.
Also, the one nitrous A/F chart you posted (the red one) shows the car getting really lean at low rpms. Better make sure that's not how the car really runs else you could damage the motor. Generally, you want a slightly leaner mixture at lower rpms than at high, but you never want to be above stoichiometric (14.7:1) at any rpm. Probably starting at like 14:1 then transition to 12-13:1 around 3500 rpms would be close to optimal.
Also, the one nitrous A/F chart you posted (the red one) shows the car getting really lean at low rpms. Better make sure that's not how the car really runs else you could damage the motor. Generally, you want a slightly leaner mixture at lower rpms than at high, but you never want to be above stoichiometric (14.7:1) at any rpm. Probably starting at like 14:1 then transition to 12-13:1 around 3500 rpms would be close to optimal.
Originally posted by Iron Lung
So if I run a higher Air fuel NA I wont get anymore power or would I be damaging the motor if I bumped it up? And same question with the nitrous. The guy at the dyno said 13/1 would be about right, but I have followed your post since I've been here and I would trust you more than him. Would a 13/1 be too lean or would I just not get anymore power out of it?
So if I run a higher Air fuel NA I wont get anymore power or would I be damaging the motor if I bumped it up? And same question with the nitrous. The guy at the dyno said 13/1 would be about right, but I have followed your post since I've been here and I would trust you more than him. Would a 13/1 be too lean or would I just not get anymore power out of it?
08-16-2002 | 02:32 PM
#44
Originally posted by Keven97SE
I think anywhere from 12:1 to 13:1 is a good target A/F ratio for mid-ro-higher rpms, even with nitrous. Stoichiometric is 14.7:1, so you're still fairly rich/safe when you're in the 12-13:1 range. It's obvious from your dyno+A/F plot that once you start getting down to the 10.5:1 range, the car is not making the torque/power it does when it runs more like 12:1.
Also, the one nitrous A/F chart you posted (the red one) shows the car getting really lean at low rpms. Better make sure that's not how the car really runs else you could damage the motor. Generally, you want a slightly leaner mixture at lower rpms than at high, but you never want to be above stoichiometric (14.7:1) at any rpm. Probably starting at like 14:1 then transition to 12-13:1 around 3500 rpms would be close to optimal.
I think anywhere from 12:1 to 13:1 is a good target A/F ratio for mid-ro-higher rpms, even with nitrous. Stoichiometric is 14.7:1, so you're still fairly rich/safe when you're in the 12-13:1 range. It's obvious from your dyno+A/F plot that once you start getting down to the 10.5:1 range, the car is not making the torque/power it does when it runs more like 12:1.
Also, the one nitrous A/F chart you posted (the red one) shows the car getting really lean at low rpms. Better make sure that's not how the car really runs else you could damage the motor. Generally, you want a slightly leaner mixture at lower rpms than at high, but you never want to be above stoichiometric (14.7:1) at any rpm. Probably starting at like 14:1 then transition to 12-13:1 around 3500 rpms would be close to optimal.
I told the guy at the dyno to not engage the nitrous below 3000 rpm, but he did anyway. Usually I don't hit it until 3500 or so.
08-16-2002 | 05:43 PM
#45
Senior Member
Joined: Sep 2000
Posts: 1,441
Originally posted by Nealoc187
95emeraldgxe stop polluting good threads with your idiocy. He is modified you fool, of course he is making more HP at the wheels than a stock max would, but you obviously were too blinded by your need to post useless posts to notice that... most of the time people ignore you on here, but when you make comments that are moronic, and then continue to post even though you don't have the slightest idea of whats going on, its quite annoying. I and most other people on this board are tired of your incessant post whoring, SHUT UP.
95emeraldgxe stop polluting good threads with your idiocy. He is modified you fool, of course he is making more HP at the wheels than a stock max would, but you obviously were too blinded by your need to post useless posts to notice that... most of the time people ignore you on here, but when you make comments that are moronic, and then continue to post even though you don't have the slightest idea of whats going on, its quite annoying. I and most other people on this board are tired of your incessant post whoring, SHUT UP.
iron long, I agree, that is a most impressive dyno pull..
And is it just me or are 99SE's unusually strong? I recall Dennis put down over 190fwhp in his AUTO '99. And he had nothing but boltons. Not even an ECU. And there are a few other 99's, whose names I can't recall, that also put up good numbers.
Hmm...hopefully I'll be seeing such numbers after I put my ypipe in
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