Performance on from an m6 trans?

[Greglogan318]

Hi all, 

I'm currently working on a very rough blank canvas. I have a 51 Chrysler New Yorker with an original hemi and m6. I'd like to dona mild build on a rather stock setup. Would it even be possible to run a 3x2 carb set up on an original m6? The thought was to hook up all the electrical transmission controls on the primary carb and run the other 2 carbs off vaccum? Any help or tips would be greatly appreciated!!

[kencombs]

The lack of responses is probably indicative of the rarity of your project!   Even fewer would still have an M6 and be modified for more power.  M6's have never been noted as a performance trans.  bullet-proof reliable, smooth to drive yes,  but not a neck-snapper.   A lot of early hemis now occupy a non-Mopar home in someone's hot rod.

 

Sure wish I still had my 57 Ford stepside w/354 and Torqueflite.

 

As to your carb plan, I can think of no reason that the trans controls shouldn't work from the center carb.  The ends can be standard linkage, progressive linkage, or vacuum operated, whatever you want to engineer.  

The 3 deuce setup will look great.  But, a single 4 barrel will probably outperform it.  And probably a lot cheaper unless you luck into a deal on a 3x2 setup.

[Dodgeb4ya]

I have a similar project ...331 Hemi/M6 with a factory truck dual 1BBL carb manifold setup. Works fine. 

All I wanted  is that it needs to run smooth, reliably and be quiet which it does all that well..

It Shifts fine too...

[Greglogan318]

Hey, thanks for the response. To be honest I was surprised to get any response at all! I'm not opposed to a 4 bbl setup. my biggest concern was integrating all the funky things Chrysler was using to link the carb to the transmission. Mostly the anti-stall switch and the circuit breaker for the interrupter switch for down shifts. I know keeping the M6 is not a great performance maker but when I got the car I was so gung-ho on keeping it stock that I went ahead and replaced the fluid coupling...should have put a torqueflite in it. I watched the Chrysler training video on the function of the M6 and I feel like it confused me more than cleared anything up! I have never seen a factory 1x1 intake! Would that be something found on a larger truck? 

[Dodgeb4ya]

The twin carb intakes came on 1957/58 model 900 dodge trucks with the 354 Hemi. Not a common one to find.

[Greglogan318]

Will a 354 intake it onto stock 51 331 heads? I've heard conflicting opinions about that swap

[Plymouthy Adams]

according to a note in my Mopar Performance book....they state a single aftermarket performance intake that fits the 331-392 early hemi...

[Dodgeb4ya]

Using any 1955 and later 354/392 intake on any early 331/354 Hemi  (1951-54) will require figuring out a thermostat setup as it's not on the intakes after 1954.

[Plymouthy Adams]

book did not make note of this but then again, this book is more dedicated to performance than that of creature comforts...thus the 'nondisclosed fact'  will try to remember to get the book back out and jot this info in as an "added factoid"

[Plymouthy Adams]

have entered this data in my book and thinking a bit more clear after a cup of coffee would have to now ask if the later water pump and housing would be adaptable to the earlier from the later?  more questions....that is the never ending line in the sand when you modify

Edited June 3, 2019 by Plymouthy Adams

[Plymouthy Adams]

I think I see the design problem...….wet intake early.....water jacketed crossover heads later.....

 

couple discussion on the internet for solutions..some involved, some a bit expensive...I never followed the early hemi, they gorgeous engines when dressed, but hp per $ formula is little skewed....

Edited June 3, 2019 by Plymouthy Adams

[Adam H P15 D30]

You need to find one of these Edmunds 2x2 wet intakes.  They used them on Allards and incorporate 2 stock carbs.  The carbs shown here had the kickdown switches on them

 

$$$$$$$$$$$$$$$$$$$$$$$$$$$$  HEMI PARTS $$$$$$$$$$$$$$$$$$$$$

[Plymouthy Adams]

looking on the internet there are a couple approaches to the later intake by drilling and tapping the intake in the vicinity of the water ports in the heads....this is then routed to a small water box that incorporates the thermostat......

[Greglogan318]

Thanks for all the feed back! I've been away for a bit. So from the sounds of it its doable but not exactly cost effective or necessarily easy to do. I'm starting to wonder if a mild cam and 8.5:1 pistons will be a better route. It's still going to be a 51 4 door Chrysler so I'm not trying to get crazy with the thing. Just needs more power ?

[kencombs]

10 hours ago, Greglogan318 said:

Thanks for all the feed back! I've been away for a bit. So from the sounds of it its doable but not exactly cost effective or necessarily easy to do. I'm starting to wonder if a mild cam and 8.5:1 pistons will be a better route. It's still going to be a 51 4 door Chrysler so I'm not trying to get crazy with the thing. Just needs more power ?

I think you're on the right track.  Why not go higher on the compression if you are doing pistons anyway?  Not necessarily into Avgas territory, but 9.5 or so.

[Dodgeb4ya]

As for the M-6 trans..

.Using a after market shifter mounted downshift button you can drive the M6 as a 1-2-3-4  four speed transmission.

Learning to do it right and smoothly it's just like a four speed. Gears are spaced just fine.

If your Hemi was coupled to the"Fluid Torque Drive" torque converter it's even way better.