350 sbc muncie m20

[Znoob]

 

My end goal is around 350hp street build with a manual transmission. I have read all the post about a Muncie m20 and was left wondering if it would make a good transmission choice for a 350 swap. Or would it be better going with a wc T5 transmission and hope it doesn't break? I don't want to go with a t56 because of the cost but I am worried that the wc T5 would not handle the power. Is there another manual transmission I should be looking at instead?

[Miles]

It comes down to your vision of how the car will be built and used.

 

Built two 240Z 350 SBC projects with 1989 Camaro WC T5 transmissions. First 240Z was built in 2001 for my teenage son. Car is still on the road. Second car built nine years ago. Daily driver. No problems.

 

Also, the T5 fits well in the car with the shifter close to the stock position.

 

Suggest that you spend a few weeks reviewing HybridZ threads on transmissions and purchase the JTR 240Z V8 installation manual. Many answers there.

Edited August 1, 2018 by Miles

[Michael]

The Muncie M20 was a "wide ratio" (for the times!) 4-speed. First gear is around 2.56, and fourth is of course 1.0.... not the best choice for a Z.

 

Unfortunately there has been little progress in V8-suited manual transmissions over the past 20 years. This is understandable, as the Gen-1 small block and Mark-IV big block have been obsolete for 20 years. Several aftermarket vendors modify the venerable T5, or its peers (Tremec etc.). At 350 hp, one supposes that a fairly conventional T5 would suit. Mine is an older build, with. Doug Nash 5-speed (not overdrive!), but then again, the engine is not 350 hp. If I were doing it all over again, I would probably go with a G-Force variant of a T5.

 

As Miles noted, the JTR book remains useful as summary of the OEM options. There may be reason to improve on it, as it were, using a blow proof bellhousing and a hydraulic throwout bearing.

Edited August 21, 2018 by Michael

[bigbore468]

Good advice from Michael and Miles.

My first build used a Muncie style 4spd transmission and it could handle 400 flywheel HP motor.

Downside is the buzzing the engine when on the freeway vs. overdrive gear with T5 or 6.

Also had a Doug Nash 5spd in that car for a while.  The DN is actually shorter than an Muncie so locating the shifter was a problem.

 

My current S30 has a slightly modified T5WC and it has held up thus far, but have not run this car on a strip with drag radials.

 

You will run into issues with the Muncie / Borg Warner 4spd shifter location, as it will be too short to exit the stock shifter location hole unless you setback the engine way past the stock firewall, even with a blowbell.

I used a Hurst super shifter and extended the mount and arms so the shifter would locate out the stock Z location and still have a short throw for all gears.

May still have that thing laying around if you need a reference.