![]() |
1 Attachment(s)
For the 6MT I have 4th gear good for about 25MPH to 125MPH and for the 7AT I have the same.
Maybe the problem is with the Dynojet's compensation for the torque factors of different gears? Or maybe the Dynojet isn't taking the different between the 6MT and 7AT into account when computing torque? It seems it should get the same answer in every gear if it was doing the math/model correctly. BTW, I attached the PDF of the iPad spreadsheet I use to compute speed/torque in gears. It is based on hand interpolating from a large dyno scan and uses the same values for auto and manual (which should be right, I think) but some day I will update with some more precise figures. It was originally done to show why you should shift at redline. |
^^^ Cool -- I'll check it out :tup:
I think it isn't compensated on the dynojet, which might be where the use a 1:1 ratio idea began... But, yes, it is clearly an artifact of the gearing... that said, I now want to dyno in 5th to compare and contrast... |
Quote:
|
Eh right idea, wrong direction, same conclusion :D
I had it backwards too :o |
Quote:
|
I could be totally wrong here, but i think the 1:1 rule was started for a few reasons.
First, cars have all sorts of gear ratios, but what we are after is engine output. It's not feasible to put an engine on an engine dyno so we go after the reading that is closest to that, and that would be a 1:1 ratio output from the engine to the gearbox. Final drive is mostly irrelevant, as it won't necessarily affect peak power, but where you make peak power. Second, disregarding overdrive, the 1:1 gear is usually towards the top of the gearseat without being in overdrive, so it takes a lot longer to go through that gear, which equals a longer amount of time for the dyno to take readings. Imagine trying to count a stack of money thats being put down bill by bill every second, then imagine trying to count a stack of money that someone just throws down all at once. |
Quote:
Anyway, so far in every run I've seen, 5th gear runs always nets higher torque and power values than 4th or 3rd. Quote:
Quote:
And this... Quote:
Finally, an interesting discussion on NASIOC on this... Dyno runs in a 1:1 gear ratio? - NASIOC Not sure if that matters for the 370Z as the autos have full lock up after 2nd gear -- i.e., a hard connection rather than strict fluid coupling (evidenced by the limited evidence of appreciable difference in drivetrain losses). |
All times are GMT -5. The time now is 04:28 PM. |
Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 PL2