M22 transmissions

[Shankin]

My tremec is not legal for the fast class so i am changing it for a m22. Just trying to figure out what one to use with around 500 to 550hp at the tires.

[HPMIKE]

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My tremec is not legal for the fast class so i am changing it for a m22. Just trying to figure out what one to use with around 500 to 550hp at the tires.

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I would just use the Supercase and build from there. Or you could even find an iron T-10 case and build a pretty stout T10. The class allows use of different transmissions as long as they were made for a GM vehicle. One nice thing about the FAST class of racing is that the lack of traction definitely saves parts. Ed Cook's kid James grenaded the Hemi crash box I built for his RR, but that was attributed to driveshaft yoke failure. It's not likely that you would have any durability issues as long as you run the bias ply tire. Even less of a chance of trans failure with a "soft-lock" type clutdh that you would be wise to run.

Give me some details on the FAST build.

MB

[Shankin]

I just sold my combination that was in my car so i could build my car up just for this class. It was making 557 rwhp and was a blast to drive but i never raced it. This will give me a chance to do something different , meet new people and see some awesome cars. With no more races than there are i will have plenty of testing time.

Combo will start with a nice BB with aluminum heads and a m22 proshifted.

[Hotrodpaul]

I wonder if anyone makes straight cut gears for the muncie? The result would be a more effecient trans with more whine.

Paul

[scuncio]

I wonder if AutoGear would make you a set of straight cut gears. If so, I am sure they'd be expensive.

I believe DNE (Doug Nash) made a pro-shifted gearset for the Muncie. I have seen DNE pro-shifted T10 gearsets. Not sure what helix angle was used in these but I gather it's a straighter angle like the M22, or possibly straighter yet. Keep in mind that straightening the helix angle will only increase the separating forces between the mainshaft and cluster gear, with a corresponding decrease in thrust (and probably a decrease in friction, but whether that's measurable is TBD). Ironically, many of the Muncie's problems stem from the separating forces between the mainshaft and cluster gear (case stretching), so are we really "fixing" anything by using the M22 helix angle? Just something to consider.

The Super Case, or the DNE cast-iron case, is probably the best bet for fixing the 'case stretch' issue.

(Note: I am not a transmission specialist and these are only my thoughts!)

[Shankin]

So the super case is a must. I will be using an adjustable clutch so that should some what save the trans along with the tires.

[Hotrodpaul]

One of the problems with the standard muncie gear angle is that it places a large thrust load on the front input bearing and retainer, causing cracked cases and thread stripping around the bolt holes when launching at high RPM on slicks. The torque also tries to seperate the gears based on helix and tooth pressure angle causing the countershaft to flex. Some of the transmissions designed for racing have a center support near the middle of the countershaft and mainshaft to control the deflection. Straight cut gears with a 14 1/2 degree pressure angle would work well, and would not create power robbing thrust friction forces. I think the Jerico boxes used in NASCAR are similar with dog style synchro engagement. These would make a nice transmission for really fast shifts if the rules permitted.

Paul