4-speed 5-speed?

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cwreese
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Joined: Thu Mar 27, 2014 7:26 am
Location: Visalia, CA

4-speed 5-speed?

Postby cwreese » Thu Aug 07, 2014 8:25 am

I recently purchased a CMC Mustang. Its a '95. Didn't purchase it from the builder and was unable to get many questions answered. Here's my question; The transmission is a 4-speed. Before I climb under it to try and find some identifying numbers, or tear it apart to see if anything is broken, has anyone heard of modifying a 5-speed to eliminate 5th gear? Maybe to save weight?
I've driven it once at Buttonwillow and only hit 5500rpm at the end of the long "dragstrip" straightaway. The rear gear is 3.55.
Doesn't appear to be a problem, I'm just suspicious.

t500hps
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Postby t500hps » Thu Aug 07, 2014 11:48 am

I have a 96 CMC mustang with a 3:27. Although my tranny has 5th, I never use it. It has been suggested I have 5th removed to save weight but haven't bothered. FYI: I red-line around 130mph in 4th which is just at the end of our fastest straight. With 3:55's I suspect your only hitting about 115-120mph in 4th......is that enough for your tracks? (or maybe the tracks in the area where the car was built)

Glenn
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Location: Ft. Worth

Postby Glenn » Thu Aug 07, 2014 12:46 pm

I didnt think removing gears from the trans was legal. Didnt there used to be a rule against it?
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BADVENM
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Postby BADVENM » Thu Aug 07, 2014 12:49 pm

How would this be enforced if it were illegal?
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suck fumes
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Postby suck fumes » Thu Aug 07, 2014 2:11 pm

You can pull the tail shaft off the tremec transmissions without removing the whole thing and look. Pretty easy to police.
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Glenn
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Location: Ft. Worth

Postby Glenn » Thu Aug 07, 2014 5:02 pm

Put it on jack stands and make sjre each gear moves the wheels.
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aschroeder
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Postby aschroeder » Mon Aug 11, 2014 10:35 am

Short of looking at the case or the shifter, theres not a lot to go on. Does it have a 5th gear shift location but no engagement? Or just 4 forward gears and reverse?

Also, are you planning on heading to any NASA events this year? I found myself taking the year off, but wouldn't mind meeting up.

nape
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Postby nape » Mon Aug 18, 2014 8:02 am

Does it have external linkage? If so, 4 speed for sure.

Super T10s are common in SCCA ASedan cars, which is what CMC loosely evolved from.
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Floranc

Re: Peur de reproduire la même erreure

Postby Floranc » Wed Mar 11, 2015 3:05 am

That's cool... i had been thinking about doing something similar, in only 2 or three colors like an old school movie poster.

cwreese
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Location: Visalia, CA

Postby cwreese » Wed Mar 11, 2015 6:25 am

It was a T5. 5th gear was removed and the detent plate in the shifter was welded up so you couldn't "accidently" go to 5th. Tranny has bee thrown in the scrap metal bin. It was cheaper to buy new than try and buy all the parts to put 5th back. I learned a lesson buying this "race ready" car. I was told it was turn-key. Turns out I had to pull both rear axles and replace all the studs (raced with loose lug nuts), replace both rear wheels, replace the drive shaft (over .030" out of round), and now I've replaced the transmission. Haven't raced yet! Oh well, experience...


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