alright guys iv saw some trannies with a 4.2, 4.4,4.5, and a 4.75 final gear. which one is the lowest gear ratio and which one has the longest gear ratio?

Also which one would be more oppropriate with a c5 swap going wtih boost?

In general with all of the trannies, what rpm range would the itr trannies be in @ 80mph?

 

not shure of the rpms at 80 , but the numerically higher ratio is a shorter gear, meaning higher rpm at the same speed and lower top speed but better acceleration.

 

at 80 with a 4.75 fd you are looking at 4400 rpm. at 80 with a 4.4 fd you are looking at 3500 rpm. The lowest gear ratio is the 4.75

 

96 Spec ITR tranny has a 4.4 FD and has the shortest gearing. 98 Spec ITR tranny has a 4.7 FD with same 1st-3rd gears as 96 spec, but with GSR longer 4th and 5th.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BlueIntegraBoy &raquo;</TD></TR><TR><TD CLASS="quote">96 Spec ITR tranny has a 4.4 FD and has the shortest gearing. 98 Spec ITR tranny has a 4.7 FD with same 1st-3rd gears as 96 spec, but with GSR longer 4th and 5th.</TD></TR></TABLE>

But put the 4.785 final drive in the 96 spec tranny and you have even shorter gears than either when stock. Just a thought.

 

hey guys i really appreciate ur help wtih this subject. i would also like to know which of the trannies would be better suited for boosting the c5. i want something with great accel. but defantally want quite a bit of top end so i can get away from mr. piggy if needed.

 

The shorter the gearing the better acceleration. Might be hard to get traction in first but if you are looking for top end go with the shorter geared tranny. Top speed will suffer. IMO the stock usdm itr tranny or usdm gsr tranny is enough for a boosted motor.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Ketone &raquo;</TD></TR><TR><TD CLASS="quote">at 80 with a 4.75 fd you are looking at 4400 rpm. at 80 with a 4.4 fd you are looking at 3500 rpm. The lowest gear ratio is the 4.75</TD></TR></TABLE>
4400 is about right for a 4.785 fd, but it'd be more like 4250 @ 80 mph for the 4.4 fd.
http://www.car-videos.com/tools/speedrpm.asp
http://www.ff-squad.com/tech/temp/Bgears.htm
(btw, i have a b16 tranny with a 4.4 fd, and it's around 4250 @ 80)

 

« Re: (99LStegra) « » 11:10 AM 1/10/2005 Reply Edit

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The shorter the gearing the better acceleration. Might be hard to get traction in first but if you are looking for top end go with the shorter geared tranny. Top speed will suffer. IMO the stock usdm itr tranny or usdm gsr tranny is enough for a boosted motor.

umm that post didn't really help....

bump.