will an OD unit take it

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freakoweirdo

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I have been desperately looking for a four speed setup for my 67 cuda with 1971 340 power> i am not having much luck.
I did find an overdrive setup for 325 bucks, includes tranny, bellhousing,flywheel clutch fork, shifter , stick and shifter rods.basically i just need the clutch linkage.
anyway: 3 questions:
1) how much abuse can the OD units take.
2) how about rpm drops, seems like in these the motor would drop too many RPMs between shifts.
3) will this flywheel setup even bolt up to the crank of a 1971 340??
4) what about the price, is that a decent price??
thanks , neal
 
The likely answer to your questions are mostly "maybe." I don't have any personal experience with the OD trans, but I have a '71 340 and a '71 A833 in my Duster. I've heard both sides with people running these with lots of power, no problem. They were after all, installed in alot of trucks. The other story I heard, but not seen any real evidence of yet, is that the alum case is weaker and prone to breakage under higher stress. Heck, anything will break under enough stress, so...

As far as the gear ratios are concerned, the big jump is between 3rd and 4th. Depending on your rear gear, tire size, etc. that may or may not come into play at the track. I can't confirm the flywheel, but that is a definite maybe. You didn't say what the OD kit came out of, assuming a SBv8, but they appear behind /6s, so better check it. I'd go for it and sort out the details later. This stuff is getting harder and harder to come by.
 
The price is very fair for what I've seen this setups go for. Especially more so if you can bolt the transmission in without worrying about opening it up and going through it.
 
I have one behind a hot 360 (around 370 HP) and it is taking the abuse of burn outs and hard launches just fine (so far 5k miles and 30k prior to that behind a hot \6).

The issue with the alumium case is the shaft the counter shaft rides on over time can elongate the holes in the case and allow the gears to seperate. If that becomes excessive BOOM. There is a fix which envolves drilling out the case and pressing in a steel bushing for the shaft. With this fix the tranny is as strong as any A833.

Mine has not had the modification.

As far as the gear spacing is concerned the 360 has enough torque that the gear spacing is not an issue for a street car, I am running 3.55 gears. Even with the \6 it was not an issue for 1-2 or 2-3, the 3-4 shift was like most vehicles with an overdrive top gear, big rpm drop.

Certainly the OD tranny is not ideal for the drag strip but on a street car it is sure nice to be able to run down the highway at 60 and be turning less than 2k rpm's.
 
I plan on putting one behind my 340 out of my race car (low 11's @ 120) that I am putting in a '72 Duster to build a hot street/car show car. I am not worried in the least about hurting it. Mine is the cast iron version but was still going to use the aluminum one if I found one. In my opinion, and I was a GM person, the worst A833 is still better than the best Muncie.
 
actually i forgort to mention its one of the earlier cast iron oD units, so the aforementioned aluminum case issue should be Ok
 
I had an aluminum cased OD out of a 76 van behind a built 383 in a 77 lil red clone with 3.91's and 3.23's. I had this truck when I was in high school...yeah I dumpped the hell outta that clutch...alot. It suprised me, I thought that it would just fall out of that truck and it held up with no problems.
 
freakoweirdo said:
oops also forgot to ask, "how can i tell if this was a slant six unit or a v8 unit??
Click to expand...

There is no difference, it's only the bell housing, flywheel and clutch that would be different between a \6 and v8. The bell housing will have the starter location at 10 o'clock verse 7 o'clock on a v8
 
dgc333 said:
There is no difference, it's only the bell housing, flywheel and clutch that would be different
Click to expand...

You did realize that the '75-'78 Iron cased A body and F body V-8 trannies aren't overdrives, right? No, not the /6 iron cased ones, V-8.
They use a 3.09 low gear with a direct drive 4th gear.

Pretty rare piece and the tip off as to it being a D.D. V-8 tranny is the bearing retainer LOOKS like an O/D bearing retainer, but has the bolt spread of the older 4 speeds.
Much like the '73-up 3 speeds in vans and trucks.

This is similar to the difference in bearing reatainers from a '69 B body 383 4 speed as opposed to a '70 B body 383 4 speed, same bearing retainer diameter, but different bolt spacing on the retainer.

Mark.
 
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