URGENT 350/ M21 installation ??????'s

[sweet n rare67]

When I put my new 350 with a Muncie M21 4speed in the stock v8 position will my trans mounts line up with my manual 3spd crossmember?? can i use my 3 speed bellhousing and clutch??? will i need a special driveshaft after all of this???

I am getting nevous about do this installation....please help

[Harold Shepard]

Are you switching from i6 to v8 or simply adding 4 speed to new motor. I did the same swap in one of my previous trucks, thing to do at the time. Everything(if v8 originally) will line up and work just as before. Word of advice- if the motor is pretty hot spend the money on a center force clutch and enjoy the 4 speed- I changed clutches it seemed like every weekend until I threw down and bought the centerforce then I started buying u- joints and rear end yokes. This is a simple bolt in remember the bolts on top go in the bell housing in a different dirction than the lower ones, can't remember which is which but I know they do.

[super-k]

This is true.When installing a Muncie 4spd in a V8 truck that has a 3spd(originally),it is a straight swap.No need to buy a single thing from the parts store.I did this one day when I was home,broke and bored.It was my only transportation and I figured,"What the hell.Beats soaps,however far I get is as far as I get".When my roomate can home from work,he couldn`t believe I had been out driving it already.Neither could I,although it wasn`t far,no gas money.

[Burnsman]

Would it be better to eliminate the 3 spd crossmember and bolt up the auto-type crossmember? I was always worried about the trans just hanging out in mid air (especially in high horsepower apps). I was worried about maybe busting the ears off the trans (alum case). I thought about installing the auto x-member and eliminating the factory 3spd stuff.

[sweet n rare67]

when i move the new 350 from the old I6 position to the v8 position will the tranny be long enough to reach the stock driveshaft?

[72C203503ONTHETREE]

Muncie had a bad habit of breaking the ears off in high horsepower cars, better get a crossmember to help support it. Everything will swap over easily though. If you get a auto crossmember you can remove the 3 speed mounts and bellhousing, it will give you more room for headers to.

[crazy longhorn]

Eveyone is right on target here, so i just have a couple thoughts to add. The M21 is the same lenght/tailspline as the saginaw 3spd(id by 7 bolt side cover). your 67 should have the proper sized centerhole in the bell(4.683, same as the car ). the 68 on bells have a 5.126 hole, & will not pilot the trans to center properly. the bottom 2 holes on the trans to bell need a bolt/nut, if you are using the truck bell(truck 3spd had the bottom 2 ears threaded , instead of the bell). the stock clutch will work, if the spline count is the same. The truck was 1 1/8" x 10 spline, where some of the Muncies were the same, some were 1 1/8x 26 spline. I do agree that a center force would be the best bet on the clutch(have one & love it!) I also agree on running an auto crossmember.....if you are moving the eng foward, the bell crossmember will not work anyway, its a different part for the V8. Just eliminate the hassle, & drop an auto crossmember in. Bolted in the same spot a 350 T would be, it all lines up. As far as driveline lenght, your shaft will be too short when you move the eng foward.....that is a 3 1/2" move! you will also need all of the V8 clutch linkage. best of luck,crazyL

[Rdrdave]

When speaking of "clutch" does this mean the clutch disc AND the pressure plate? I've been thinking of the centerforce dual setup but am not sure if this means the disc or just the special pressure plate. ANy help is much appreciated. I'm 2 steps from dropping some $$ on my setup. Already got the M21 and comp shifter. Need a bellhousing and new clutch set.

[69 longhorn]

yes, disc & press plate, the throwout bearing will be sold separately (for application). I run a dual friction setup on my longhorn, & will say its worth the bucks (it has been abused hard, with no issues)......69L

[Rdrdave]

Well, i ended getting a great deal on a centerforce II setup with clutch, pressure plate, throwout bearing and flywheel. I was selling at the swap meet and ended up buying more than I sold! I also found the 11" bellhousing i needed. Scores! Wife said it was ok!