Need Help using a 2.73 rear for gear swap

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Oct 11, 2003 | 06:00 PM

99C5ragtop

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Pro

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From: her AK

Need Help using a 2.73 rear for gear swap

Does anyone know what is necessary to make a 2.73 carrier accept a 3 or 4 series ring and pinion?

I know there is a spacer needed inside to line up thegears correctly but does anyone have the specs?

I have heard the 2 series reluctor needs to be changed out with a 3 series reluctor. Is that true?

Another person told me that the internals of the case have to be machined but looking at it I can't see where.

Can anyone help? I know shops are using them successfully, most notably DTE.

THX!
MM

Oct 12, 2003 | 10:39 AM

99 The Hard Way

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From: Pensacola FL

Re: Need Help using a 2.73 rear for gear swap (99C5ragtop)

DTE put 4.10's in my 2.73 case for my 99 FRC. Phil is very good to work with & can give you all the details. Drop him an email or give him a call. No problems with mine so far. SCOTT

Oct 12, 2003 | 11:50 AM

jeanlucpicard

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From: The Woodlands Texas

Re: Need Help using a 2.73 rear for gear swap (99C5ragtop)

The problem with using a 2:73 rear end casing has been documented on the CF several times. The casing does not have the amount of structural strength that the 3:42 casing has. There are more ribs crossing and supporting the 3:42 casing. The 2:73 casings tend to crack and split after larger gears are installed and the owner then "hot-dogs" (like anyone would) the car. You may want to consider getting a 3:42 gear casing to use instead.

Oct 12, 2003 | 01:40 PM

99C5ragtop

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From: her AK

Re: Need Help using a 2.73 rear for gear swap (jeanlucpicard)

I do not know if the cases are different but DTE has several customers using 2-series carriers and one I know of running nines!!! I know they are good cases I just want details on what's necessary to convert them.
:cheers:

Oct 12, 2003 | 01:42 PM

99C5ragtop

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From: her AK

Re: Need Help using a 2.73 rear for gear swap (99 The Hard Way)

99thehardway...thanks for the heads up...I'll try Phil but am afraid that they would not share their process with me.

Oct 12, 2003 | 02:59 PM

Mike Mercury

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From: S.W. Ohio. . . . . . NRA Life Member

Re: Need Help using a 2.73 rear for gear swap (99C5ragtop)

Quote:

I do not know if the cases are different

there is a difference between the 2 and 3 series cases.

One vendor has figured out a way to add the other gear sets to the 2 series case. I don't think they sell a DIY kit - or offer DIY instructions. It's their baby and they will do the upgrade for you if you send them your carrier.

I once read that the Getrag procedure for changing gears in the 3 series carrier was something like 15 pages long; using a hoard of special tools, guages, and shims. Point being that even the simple one (3 series)... it's beyond the capability for 99.9 percent of C5 owners.

I'd suggest doing a search and determine the vendor that figured out the 2 series upgrades and send them your carrier for the change.

.

[Modified by Mike Mercury, 5:48 PM 10/12/2003]

Oct 12, 2003 | 04:50 PM

SFVetteman

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From: San Francisco CA

Re: Need Help using a 2.73 rear for gear swap (99C5ragtop)

Quote:

I know shops are using them successfully, most notably DTE.

To the best of my knowledge, DTE is the only shop willing to put gears in the weaker 2.73 case. Most people, except those with broad bills and web feet and a few others would rather have the 3.15-3.42 case.