Headers, O2 sensors, JWT ECU, & air/fuel ratio question
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Don't even think of the current 5 speed from Nissan [if it could be adapted to fit]..........the Q would be turning 2400 rpm at 60 mph in 5th, fuel economy would drop by 20% on highway.
Not that much stronger than what we have even more torque reduction at shift and the electronic throttle to decrease power at during after shift.HOWEVER the QX56 transmission is a little better in that they tweeked the first 3 gears. But the span is still pathetic at 4.5887. But at 5360 pounds the engine needs some rpms.
1st 3.827 .....12.85 total torque multiplication2nd 2.368 3rd 1.520 4th 1.000 5th 0.834 reverse 2.613 Final drive ratio 3.357
Not that much stronger than what we have even more torque reduction at shift and the electronic throttle to decrease power at during after shift.HOWEVER the QX56 transmission is a little better in that they tweeked the first 3 gears. But the span is still pathetic at 4.5887. But at 5360 pounds the engine needs some rpms.
1st 3.827 .....12.85 total torque multiplication2nd 2.368 3rd 1.520 4th 1.000 5th 0.834 reverse 2.613 Final drive ratio 3.357
Quote »I warned them* in 2002 when I first saw the transmission ratios and diff gear ratio.[/quote]
That there stuff about the combo of transmission/diff ratios is some of the best shiet that I have learned so far as it really explains a lot about the accleration rates and fuel economy of many cars with the same HP rating. Now I know why all the car mags have these transmission ratios per gear listed and the diff ratio so that a "rea" tech junky can put them into a spreadsheet and compare with other cars to get some theoretically close "real" stat comparisons between cars.
That there stuff about the combo of transmission/diff ratios is some of the best shiet that I have learned so far as it really explains a lot about the accleration rates and fuel economy of many cars with the same HP rating. Now I know why all the car mags have these transmission ratios per gear listed and the diff ratio so that a "rea" tech junky can put them into a spreadsheet and compare with other cars to get some theoretically close "real" stat comparisons between cars.