CRG Discussion Forum

Camaro Research Group Discussion => Mild Modifications => Topic started by: Michaels69LM1 on April 30, 2011, 04:41:30 PM

Title: 69 Camaro Auto Trans Swap
Post by: Michaels69LM1 on April 30, 2011, 04:41:30 PM
Hi, I'm new to the forum and need some advice. I have a 69 LM1 Camaro with 350 - turbo 350 auto trans that I would like to swap for a 4speed, Console car horseshoe shifter. The question is which 4 speed?  I have contacted a few people in the industry some suggest the M20 wide ratio other suggest the M22 Close ratio. I have considered the tremec tko500 for the overdrive, but would like to keep the somewhat of the originality of the muncie trans.
I will be swapping the 350 engine 255hp for a 383 stroker with 525hp. also have 3.73 gears in the 12bolt.
Would I need to change the drive shaft and trans cross member with this trans swap?
Any help would be appreciated....
Title: Re: 69 Camaro Auto Trans Swap
Post by: william on April 30, 2011, 06:13:59 PM
All 6 cylinder & small-block 1st gens use the same crossmember.

The 383 is not a high rpm engine so a close-ratio [M21 or M22] trans is not needed. Whatever driveshaft you have isn't going to last long with 525 hp so have a new high performance 3" unit made. There are a number of shops that can do that for you.

You will also need new pedals [69 only] and a cross-shaft [aka Z-bar]. Will need a longer speedo cable; Muncie was routed to the pass side.
Title: Re: 69 Camaro Auto Trans Swap
Post by: qwertyme77 on May 01, 2011, 09:47:25 PM
ran across this article a few years ago when I thought of putting a 5 or 6 speed into my car. I haven't done it yet, but would really like to. read the article all the way through, as there are a few issues with going to a newer trans.

http://www.chevyhiperformance.com/techarticles/48418_t56_six_speed_swap_early_camaros/index.html

also, some info on types.

http://www.ttcautomotive.com/English/products/tremec.asp

good luck in what ever you choose.

Title: Re: 69 Camaro Auto Trans Swap
Post by: Michaels69LM1 on May 02, 2011, 02:42:53 PM
William, thanks for the reply. In your opinion what 1st gear ratio would be best? 2.52 or Lower? I really don't drive the car on the highways and would like the torque off the line. Your thoughts?
Title: Re: 69 Camaro Auto Trans Swap
Post by: william on May 02, 2011, 10:00:12 PM
William, thanks for the reply. In your opinion what 1st gear ratio would be best? 2.52 or Lower? I really don't drive the car on the highways and would like the torque off the line. Your thoughts?

All vintage 4-speeds are 1.00:1 in 4th. All the same on the highway.

'Peaky' engines like the Z/28 need close ratios to keep the engine in its narrow power band. The wide has a 2.52:1 1st gear for a total of 9.4:1 with a 3.73 axle. But you pay for it in the 3-4 shift; the engine will drop from 6500 to 4500 and it feels like a stiff headwind. Your 383 will have a broad power band and the drop won't be as noticeable. Don't think the 383 needs to wind that far anyways.

Another factor is the torque the Muncie trans was designed to withstand. A wide has more multiplication and your 383
could be near the ragged edge for a Muncie.

Title: Re: 69 Camaro Auto Trans Swap
Post by: Michaels69LM1 on May 05, 2011, 05:43:24 AM
Thank-you, I have a much better idea of what is going to be the right muncie, I appreciate the help.
Title: Re: 69 Camaro Auto Trans Swap
Post by: Marty on May 07, 2011, 06:02:18 PM
The '429 tail housing on the Muncie trans has the speedo on the driver's side and I think you could use the same speedo cable as the auto trans.
Title: Re: 69 Camaro Auto Trans Swap
Post by: Michaels69LM1 on May 18, 2011, 02:55:32 PM
Hey guys any suggestions on clutch pressure plates, I'm leaning towards Hayes 11" but I'm open to suggestions. Also it looks like I may have to cut a hole in my floor for the shifter, whats the best way to line this up correctly? Any help is greatly appreciated