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Discussion Starter #1 (Edited)

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That's a big number for the 458, actually - stock? What kind of dyno? Really 5th gear pulls? My experience has been 3rd gear for power pulls and I want to ay 5th gear will generate a bigger number and less drivetrain loss due to the gear ratio having less inertia change for the transaxle as it does not get spun up as fast due to the closer to 1:1 coupling with the engine.

Fun and thanks for sharing
 

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Discussion Starter #5
That's a big number for the 458, actually - stock? What kind of dyno? Really 5th gear pulls? My experience has been 3rd gear for power pulls and I want to ay 5th gear will generate a bigger number and less drivetrain loss due to the gear ratio having less inertia change for the transaxle as it does not get spun up as fast due to the closer to 1:1 coupling with the engine.

Fun and thanks for sharing
Dyno brand listed above, Dyno Dynamics. The Tuner wanted a gear closest to 1:1 so that is why 5th gear was used.

Estimate is 15% drivetrain loss usually. 458 is stock. This brand of Dyno also typically reads low compared to others.
 

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Interesting - Fabspeed will regale you with 458s making 450 rwhp stock so that their tune + headers + cat makes another 70 hp at certain rpms:

http://www.ferrarichat.com/forum/458-italia/352748-fabspeed-458-performance-package.html

what to believe?:rolleyes:
Yes I just looked at their Dyno measurements yesterday. Around 425 for a 430 Scud, and 450 for a 458.

Scud seems about right stock, 458 seems low. They use a Dynojet Dyno for their measurements.

Did some reading on Dynos, and since not many every read exactly the same, the only thing they are good for, is measuring before and after performance of a car when you add modifications. Would still be nice to know if a car is producing what it should stock. Guess we have to trust that manufacturers know what they are doing. :rolleyes:
 

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Interesting - Fabspeed will regale you with 458s making 450 rwhp stock so that their tune + headers + cat makes another 70 hp at certain rpms:

http://www.ferrarichat.com/forum/458-italia/352748-fabspeed-458-performance-package.html

what to believe?:rolleyes:
We dyno'ed the 458 in 5th gear, which has a ratio of 1.03. I can provide graphs to show this, or you can watch the video and see clearly the gear indicator on the dash shows a 5.

In reality you can dyno a car in any gear you want, so long as when you are making comparisons, you maintain the same dyno procedure. Dyno'ing in 1st or 2nd gear will not provide good data however.

I have heard some guys make claims about why you should dyno in X gear because it is more efficient ect. ect.......in reality they are just looking for a higher number or higher graph to make themselves feel better. On the 458 as discussed here dyno'ing in 3rd or 4th will give you more torque multiplication to the wheels and thus more area under the dyno curve. Fabspeed as a company in general is not about peak numbers - we care about deltas, as do most of our customers.

Some of the cars we do are dyno'ed in 4th gear to keep dyno drum speeds down, that is the only reason.
 
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