Gen4 vs Gen5 VQ30 Performance: The Final DYNO Showdown
10-17-2002, 11:04 AM
#45
That hump at 3500-4000 rpm on Gen 4 dynos with the the fixed US manifold must be due to manifold resonance. That rpm range looks to be where the resonance frequency starts to oscillate alot, thereby pulling more air into the system, and the ECU follows thru with more feul. That would also explain why the Gen 4 NON VI dyno is so ragged (peaks and troughs)compared to the 5th gen, and also a 4th gen with a VIM.
Also interesting to note that Hybrid intakes make the 4th gen dyno lumpier with bigger peaks and valleys, but CAIs make them smoooth and linear.
DW
Also interesting to note that Hybrid intakes make the 4th gen dyno lumpier with bigger peaks and valleys, but CAIs make them smoooth and linear.
DW
Originally posted by Dave B
The VIM seems to smooth out the torque curve of the VQ. Why? I don't know. Maybe the runners are slightly shorter. The VIM-VQ cuts off the two humps in the torque curve where all US-spec VQs get their peak torque. In around town driving, I use to be able to a feel a kind of turbo-like rush from 3000-4000rpms. With the VIM, it's not there. When it comes to track racing, that drop in torque will not affect ET because, if you're driving right, you don't spend anytime from 3000-4500rpms, expect in 1st. BTW, I lost 7-8fwtq
Of course of the VIM the pull after 5000rpms is very impressive. The car feels much smoother in the upper RPMs.
The torque curve of the VIM-VQ and the VE are similiar, but the VQ will be making on average about +10-15fwtq from 2000-5500rpms over the VE. After 5500rpms, the VIM-VQ has a huge advantage.
Dave
The VIM seems to smooth out the torque curve of the VQ. Why? I don't know. Maybe the runners are slightly shorter. The VIM-VQ cuts off the two humps in the torque curve where all US-spec VQs get their peak torque. In around town driving, I use to be able to a feel a kind of turbo-like rush from 3000-4000rpms. With the VIM, it's not there. When it comes to track racing, that drop in torque will not affect ET because, if you're driving right, you don't spend anytime from 3000-4500rpms, expect in 1st. BTW, I lost 7-8fwtq
Of course of the VIM the pull after 5000rpms is very impressive. The car feels much smoother in the upper RPMs.The torque curve of the VIM-VQ and the VE are similiar, but the VQ will be making on average about +10-15fwtq from 2000-5500rpms over the VE. After 5500rpms, the VIM-VQ has a huge advantage.
Dave
10-18-2002, 09:58 AM
#46
Dyno plot says I have the most area under the Administrator curve
Thread Starter
Join Date: Jul 2001
Posts: 7,060
Yeah Keven97SE posted about the resonances on the 4th Gen USDM OE intake manifold. Peaks at 1200, 2400, and 3600rpm. But dips at 1800rpm and 3000rpm. It's then pretty flat after 3600rpm, but drops off after 4800-5000rpm or so.
I was testing this out yesterday while stuck in stop-n-go (and also annoying the people behind me
) and you really can feel it with the 5spd.
I was testing this out yesterday while stuck in stop-n-go (and also annoying the people behind me
) and you really can feel it with the 5spd.
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