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View Full Version : [B]240SX/Silvia transmission swap vehicle speeds vs rpm[/B]


bshotts
07-14-2008, 11:39 AM
Doing some research on common trans swaps for the S chassis, I finally had enough of hand calculating to use the ole noggin and put together this handy Excel doc.

You’ll find the first tab lists some common gearbox ratios from the Nissan family and others (ie SR20DET, S15 SR20DET, VG30DETT, 2JZGTE) and will have two gray boxes that ask for total tire diameter and final drive gear ratio. Each different trans has it’s own appropriate tab listing vehicle speed based on engine RPM.

I found this useful for many things: comparing speeds and RPMs between different transmissions, finding cruise RPMs, finding 60 mph RPMs, seeing changes due to swapping differentials, top speeds etc. I really wanted to have an end-all spreadsheet to see the results of all these different combinations.

The spreadsheet currently has the 4.08 final drive ratio which should be standard 240SX final drive (differential) ratio and an approximate value of total tire diameter with OEM 16” S14 wheels. Again, these values can be changed for individual wheel/tire combinations and different final drives.

Let me know if you would like to see any other transmission included.

Bryan

Link to file is below:
http://www.mediafire.com/?mehaq0zko1z

cgtdream
07-14-2008, 01:50 PM
Wow this is pretty cool bro. Think i might go for a read on transmission and gearing so ill better understand what ya got here :bigok:

bshotts
07-15-2008, 08:11 AM
Has anyone found this useful? If so, I motion to have it archived in FAQ or stickied for tech just so we don't lose track of it.