gear drop at shift calculator

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Aug 14, 2009 | 05:07 PM

#11

vanillagorilla

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From: Arizona Bay

Quote:

Originally Posted by NyteSnyper

Well, I use these for the nv3500 and they seem to be pretty accurate... My truck seems to hit a brick wall in 3rd gear til it wraps back up into the 3500 range...

1st- 5.61
2nd- 3.04
3rd- 1.67
4th- 1.00
5th- .75

Those gear ratios are terrible. Does he even use 1st gear? I'm surprised it builds any boost in first gear since there's probably very little load on the truck and 1st gear is over so fast. Anyway:

3.73's 30" tall tire
1st gear @ 6000rpm, 26mph -> 2nd gear shift 3300rpm
2nd gear @ 6000rpm, 47mph -> 3rd gear shift 3300rpm
3rd gear @ 6000rpm, 86mph -> 4th gear shift 3600rpm

2nd, 3rd and 4th are very, very similar to 1st, 2nd and 3rd in a 60E, however with an auto and a decent torque converter, rpms won't drop as much between shifts. But with a clutch, there's no slipage so the rpms will drop more between shifts.

Aug 14, 2009 | 07:48 PM

#12

TURBHOE

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From: Jacksonville FL.

Quote:

Originally Posted by vanillagorilla

Get a BOV on there if you don't already. That will help between shifts. Also what gear ratios does the NV3500 have that the rpms drop below 2000rpm after a shift. Is he short shifting or something? I say get a BOV, do the drill mod, get a short throw shifter and powershift the SOB. Then look into changing gears.

its got a bov but its a cheap *** small one. i think the gears actually drop to about 3400 each shift but it takes him so long to shift. we ordered the -4 adapters to takeout the stock line and put in a -4 line to make the hydrolics work faster. then he is going to order the shirt shifter. we finally found one.

the gears are like 4.01 2.33 1.39 1.00 .73
gear drop was like 34-3600 but the way he shifts lol. and the turbo take a second to spool up. i would swap to a .68 a/r exhuast housing but i doin't know if it would kill flow in the upper rpm's.