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Thinking of C4 transmission - what gear ratio?

25K views 5 replies 4 participants last post by  MYLITTLEHO  
#1 ·
Thinking of C4, what gear ratio?

Heres the thing, my car makes 287rwhp/314rwtq n/a... However I plan on boosting it to around the 500rwhp range.
My buddy has a race built c4 with man. valve body and 3500 stall converter.
I am running a 3.73 gear ratio rear end right now.

I want to know what it would take to be able to drive this thing daily, but not necessarly on the highway. Would I be winding out the motor at 60mph? (figure of speach)
Any suggestions are welcome.
 
#3 ·
Do you have an AOD or a T5 now? Run the car in "D" if it's an AOD or 4th if it's a T5 and that's your 1:1 ratio, the same as 3rd gear in a C4. That'll give you a decent idea of what it'll run at with your current 3.73's. Then you might add a few hundred RPM's because I'd bet that C4 converter is a non lockup. I wouldn't suggest a C4 for a daily driver. I get annoyed with my AOD/3.73/lock up converter car as a daily driver because it turns about 2,200 revs on the highway in OD. 500rwhp + 3500 stall + manual valve body doesn't sound like a good daily driver to me even if it had like 3.27's or something...but there are many people daily driving stuff just like that. It's all a matter of how much you can tolerate. I know I wouldn't try a non overdrive trans as a daily though...just my two cents.
 
#4 ·
Had a Performance Automatic Reverse Pattern Manual Shift C-4 in my 94 for a while. In the rear were 3.55's. This was pretty driveable, but I did not like running around 65-70 for any long period of time. Rev'd a little too high. But man was it great on acceleration.

Can't remember the specifics, but I do remember the shift light turning on at around 100 or 105 at 6500.
 
#6 ·
using this transmission calculator
http://www.geocities.com/z_design_studio/transmission_z28_6.html

You would need a nice tall tire... with a 255/50r16 stock pony wheel tires and 3.73's with a C4's 3rd gear (1:1) you'd have to run the motor up to 6253rpm to trap 130mph.

(For use to plug into the RPM calculator) The c4's 1st gear is 2.46:1, 2nd is 1.46:1, and 3rd is 1:1