07 350Z and 08 G37 same dyno same day

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Feb 23, 2008 | 09:53 AM

#41

MrRyte

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Quote:

Originally Posted by HR_Z-Ballz

I think thats the best logical answer yet for those who are still stock...With my last car, I went to three different dynos over the course of year and could never get consistent numbers.

Also, how often are the dynos themselves tested and calibrated? Are they checked after every run or every now and then?

Feb 23, 2008 | 10:02 AM

#42

phunk

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Quote:

Originally Posted by MrRyte

Also, how often are the dynos themselves tested and calibrated? Are they checked after every run or every now and then?

the dynojet dyno is a very simple device and there is no calibration to test. its nothing but a very very large and heavy roller with a single trigger on the axle shaft. the calibration is in the math, which never changes.

Feb 24, 2008 | 12:40 PM

#43

warmmilk

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Quote:

Originally Posted by phunk

what is the gearing difference on the cars? transmission gearing? final drive gear ratio? when i went from a 3.5 to a 3.3FD, my dyno numbers dropped by the exact same percentage as the gear ratio difference.

i'm not sure on the differences, i know that the 07z still has the same 3.5FD as the previous year z's, but i'm not sure on the g37 FD

Feb 28, 2008 | 11:20 AM

#44

Frostydc4

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Quote:

Originally Posted by phunk

Hypothetically speaking would the same thing happen to an AT car going to a lower final drive and vice versa? Thanks.

Last edited by Frostydc4; Feb 28, 2008 at 11:32 AM.

Feb 28, 2008 | 11:33 AM

#45

Frostydc4

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Quote:

Originally Posted by warmmilk

i'm not sure on the differences, i know that the 07z still has the same 3.5FD as the previous year z's, but i'm not sure on the g37 FD

The G37 has a 3.7FD

Feb 28, 2008 | 11:36 AM

#46

T_K

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G37 Transmission Specs:

Gear ratios (:1)
5 A/T 6 M/T
1st 3.841 3.794
2nd 2.352 2.324
3rd 1.529 1.624
4th 1.000 1.271
5th 0.839 1.000
6th - 0.794
Reverse 2.764 3.446
Final drive ratio (:1) 3.692

Looks like everything stayed the same except the final drive, and both auto and manuals get the same final drive ratio, meaning probably use the same pumpkin this time around. This makes a lot more sense, considering the 7500 rev limit of the HR motors, would give the car a little more pep, going from 3.5 to closer to 3.7.

TK

Feb 28, 2008 | 12:45 PM

#47

Frostydc4

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^^

Also the 07+ G35 sedan (AT & MT) dyno pretty much the same and they run very similar 1/4 time with the same trap speed. Also all 280whp 07+ 350Z's I have seen have had the FD swapped for a 4.08. Thats why I asked the question. I would love to compare the 07+ Z and the G37 dyno runs with both cars using the same final drive

Feb 28, 2008 | 02:42 PM

#48

T_K

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I always thought a shorter overall gear, i.e. higher numerical gear, gave lower numbers than a taller overall gear, i.e lower numerical number.

TK

Feb 28, 2008 | 03:21 PM

#49

itsjiggajames

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Quote:

Originally Posted by Frostydc4

Negative.. only a few people have a 4.08. Rkemp is in the 280s without a 4.08.

Feb 28, 2008 | 08:18 PM

#50

Frostydc4

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Quote:

Originally Posted by T_K

I always thought a shorter overall gear, i.e. higher numerical gear, gave lower numbers than a taller overall gear, i.e lower numerical number.

TK

This is what I thought also b/c of the difference between the speed of the rollers & engine rpm but someone posted that they lost power going to a taller FD

Feb 28, 2008 | 09:31 PM

#51

Peak350

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Quote:

Originally Posted by Frostydc4

This is what I thought also b/c of the difference between the speed of the rollers & engine rpm but someone posted that they lost power going to a taller FD

You lose measured power (especially on a non-loading dyno) because the gearing puts more torque at the wheels, so it accelerates the drum faster, but the relative increase also makes the weight of the flywheel, driveshaft, etc. more apparent.