swapping early 3.09 1st into later case

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mbaird

mbaird

mbaird
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I searched but couldnt find a thread on this.

I have 3 833s ... 2 67-68s and 1 early Ball and trunion with a low 3.09 1st gear set.

Is it possible to swap the low gear set into the later trany ? And what does it entail ?

I want the low gear to mask the engines pulses at low speeds in 1st. Not to mention it cant hurt my 60ft .
 
I have the same question. I have a early 3.09 a-body trans and late model 2.66 a-body (lever style side cover), and am looking to use with a 3.00 rear axle.
 
It worked for me. I bought just the gear-set from Passon Performance and it fit right in. You have to swap the entire set in; all 5 gears.
The gear ratio change is not in the low gear but in the cluster drive;that is, the front part of the cluster and the input gear. AFAIK,ALL A833s have the same First gear.
The 3.09 set makes a great street set cuz you can run 3.55s with them, and the car rockets off the line,like it had 4.12s, with the old 2.66 starter.

I don't get the "masking" business tho..........
 
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basically you can use any tail shaft in any 833, all the tail shaft internal splines are the same.
 
bbab3 said:
I have the same question. I have a early 3.09 a-body trans and late model 2.66 a-body (lever style side cover), and am looking to use with a 3.00 rear axle.
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You lost me
The covers are interchangeable.
The forks go with the covers.
You can cut the steel forks to use them in a brass fork cover.
When using something like a 3.0 rear-end, using a 3.09 low box is better than using a 2.66 low tranny.
But a 3.0ish rear can be a real bear with a low-torque engine, when you hit second gear,cuz the rest of the gears are practically identical between the boxes, and the 3.09 will run outta revs at a slower roadspeed
3200rpm in 2.66low is about 32mph. Second will be 2278.
3200rpm in 3.09low is about 28mph. Second will be 1993
To get the same 32mph/2278rpm into second, with the3.09 box, you will have to rev to 3685.
3685rpm in 3.09low is about 32mph. Second will be 2278.
 
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AJ/FormS said:
You lost me
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What I am referring to is am I better off taking the gears out of the older case and using them in the later case and retaining the later style interlock side cover or use the older ball/detent style. Additionally, what synchros should/can I use older or newer? I'm planing on rebuilding the transmission. Sorry did not meet to take over the thread!
 
I'd swap the main shaft and tail housing. The newer synchros are supposed to be the best. I tend to keep the main housing, cover, and shifter arms, reverse lever together if possible.
 
I understand your point. Quite a while back I owned a '68 Fb 340 formula s barracuda with 3.07 rear and the 2.66 trans. The cam was not or low end torque, but it was workable. I have talked to the tech's at Hughes and Comp Cam about what I am planning on doing and both told me basically the same thing, custom ground cam for the 340 combo I have planned due to need for low speed torque. The '67 Fb barracuda I have is going to be more about handling, drivability and road trips.
 
bbab3 said:
What I am referring to is am I better off taking the gears out of the older case and using them in the later case and retaining the later style interlock side cover or use the older ball/detent style. Additionally, what synchros should/can I use older or newer? I'm planing on rebuilding the transmission. Sorry did not meet to take over the thread!
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Yes you can keep the ball detent style cover.
The later rooster comb style suck imo.
 
bbab3 said:
What I am referring to is am I better off taking the gears out of the older case and using them in the later case and retaining the later style interlock side cover or use the older ball/detent style. Additionally, what synchros should/can I use older or newer? I'm planing on rebuilding the transmission. Sorry did not meet to take over the thread!
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You can put either synchronizer system into either box and either cover onto either box. They say the late style brass is stronger, but on the street, I haven't proved it. They say the steel forks are stronger, but on the street I have never broken one.
I have put hundreds of these together since the 70s. For about 6 years I did a lot of assembly line work on all kinds of transmissions. In that line of work,I doubt we ever got the same gears back together. We/I just slapped 'em together. I had parts stacked up on the shelves and just took whatever I needed.
Saginaw 3 speeds were a worst case. The strippers, after they came out of the washers, just threw everything together in shopping carts, gears in one cart, cases in another. "Here's your job for today" they said. I think I used to slam them out 8 per day. They were so easy. Not so on the Muncie 4 speeds. What a piece.
I always liked doing Top-loaders.
Then they put me on bigger stuff
And bigger
And bigger.
I did one Powershift set-up from some piece of heavy equipment, I think it took me several days to overhaul. They made me take it apart, thinking that would help. I said "Hell-no, get me a picture, or a cross-section, sumpthing, I'm no Einstein." They got me one. It worked after I got done, and no pieces were left over; Not one.
They gave me more and more of that. I loved it.
But the pay was crap, so I moved on. Never found another job I liked as much as that one until 12 years later.
 
I did this in my 64 dart, like 35 years ago, so my memory is a little fuzzy. But I used the main shaft and tailshaft hsg from the slip spline transfer to the old ball and trunnion main case. I highly recommend it. Loved it.
Really good behind a 225 slant, too.
 
bbab3 said:
I understand your point. Quite a while back I owned a '68 Fb 340 formula s barracuda with 3.07 rear and the 2.66 trans. The cam was not or low end torque, but it was workable. I have talked to the tech's at Hughes and Comp Cam about what I am planning on doing and both told me basically the same thing, custom ground cam for the 340 combo I have planned due to need for low speed torque. The '67 Fb barracuda I have is going to be more about handling, drivability and road trips.
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That is why I build a 367 with a 4.04 bore. She's my stroked 340. Those cubes come in very handy at low speed. And I had the same idea as to the end use, back in 99 when my 68 S-clone hit the road,namely; handling, driveability and road trips.
Good luck on your combo!
 
Thanks. I apologize of taking mbaird's tread. This transmission issue is one of many upgrades I have planned. I have been wanting to start a thread about my barracuda and just haven't gotten to it. To many monkeys on my back, and they're now morfing in to male lowland gorillas. Not fun. I am looking to switch out the main shaft, tail shaft, and synchro assembly. The interlock side cover I didn't want to use. I down shifted my '71 340-6 'Cuda from 3rd into 2nd when entering a turn fast and it locked in both gears, makes for a fun time. Anyways thanks for the input.
 
bbab3 said:
Thanks. I apologize of taking mbaird's tread. This transmission issue is one of many upgrades I have planned. I have been wanting to start a thread about my barracuda and just haven't gotten to it. To many monkeys on my back, and they're now morfing in to male lowland gorillas. Not fun. I am looking to switch out the main shaft, tail shaft, and synchro assembly. The interlock side cover I didn't want to use. I down shifted my '71 340-6 'Cuda from 3rd into 2nd when entering a turn fast and it locked in both gears, makes for a fun time. Anyways thanks for the input.
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So you broke a brass fork Then?
 
AJ/FormS said:
So you broke a brass fork Then?
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No, the flat bar mounted on the side cover broke,and somehow it did not come all the way out of 3rd when I shifted into 2nd. I remember I had to replace the entire cover. May have broken a fork arm also. Not sure it happened 30 years ago. Do remember the slide on a mountain road at night though.
 
dont worry about stealing the thread... this is the info I was looking for.

When I said "mask the cam " I meant feeling the pulses of a bigger cam at low speeds in 1st. The 3.09s will bring the rpms up in 1st without running 4.56s or such.
 
mbaird said:
dont worry about stealing the thread... this is the info I was looking for.

When I said "mask the cam " I meant feeling the pulses of a bigger cam at low speeds in 1st. The 3.09s will bring the rpms up in 1st without running 4.56s or such.
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That's kinda what I thought that you mighta meant
I had the 292/292/108 cam for a while and at 11.3 Scr, the pulses down low were quite strong. I solved that with less initial timing. I installed a dash-mounted, dial-back timing device, and cranked the timing back to 5 degrees, for those times when she got a little jumpy.
If you haven't played with your T-port sync yet, I found some smoothness there too.That cam Likes a lot of Idle air bypass.
I run 3.55s and the 3.09, making the starter gear equivalent to 4.12s. At the other end, I run a GVOD, which turns the 3.55s into something like 2.76s, I forget exactly. But yeah, down at 600rpm that 292 hammered pretty good with 11.3 Scr, before I took the timing out.
See one thing I don't get is everybody always wants to crank the idle-timing up into the 20s. I guess with an automatic and a hi-stall one could get away with that,and then the down-low tune can be pretty sloppy. But for a streeter with a stick car, that just won't fly;the low-speed circuit needs to be pretty right on.
If you put that 3.09 in, you will be glad you did.
I got rid of that cam.
I now run a 276/286/110; lotsa more power down low, and as a streeter, I don't miss the top end rush, cuz, you know, there's this speed-limit thing.Oh yeah, the down low is no longer jumpy. Now I still use that timing device to slow the idle down to where I can parade the thing. Sometimes I run it into retard, and she smooths right out.
Happy motoring!
 
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Yes, it can be done and that is what I ran for years in my 71 Duster behind my 440. I also plan to run that same trans behind my 500 in my Barracuda, at least until I get a chance to install my T56. My best friend built it for me. He did exactly that, took the 3.09 from the early trans and put it in the late case.
 
Brad4406 said:
Yes, it can be done and that is what I ran for years in my 71 Duster behind my 440. I also plan to run that same trans behind my 500 in my Barracuda, at least until I get a chance to install my T56. My best friend built it for me. He did exactly that, took the 3.09 from the early trans and put it in the late case.
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Hang-on
You're putting a 500 in a Barracuda, and you think you need a 3.09 low gear?
That 3.09 is a torque multiplier, to the tune of 3.09/2.66= plus 16%. We use it behind low-torque engines to help get them off the line.Or behind engines saddled with very low-perf. street gears.
Somehow I'm having trouble imagining a low-torque 500.....
or a 500 with 2.76 gears........
 
AJ/FormS said:
Hang-on
You're putting a 500 in a Barracuda, and you think you need a 3.09 low gear?
That 3.09 is a torque multiplier, to the tune of 3.09/2.66= plus 16%. We use it behind low-torque engines to help get them off the line.Or behind engines saddled with very low-perf. street gears.
Somehow I'm having trouble imagining a low-torque 500.....
or a 500 with 2.76 gears........
Click to expand...
I never said I needed it, but that I plan to use it. I didn't need it behind my last 440 either, but improvements to 60' times don't just happen; you have to be creative when options are available.

Engine and 1st gear ratio are only pieces in the entire puzzle of getting hp to the pavement; you must take rear tire size and rear axle ratio into consideration in that calculation as well. Rather than you having to look through my build thread, my expected tire size will be 30.5" or 31" and the two rear axle ratios I currently have available are 5.38 and 4.10; however that could always change as well. Plus, the 4-speed is only expected to be in temporarily as I plan to install my T56 the winter after I get it on the road and all the bugs worked out.
 
OK, I forget that some of you guys are drag-racers.
The 5.38s and 3.09 team up to be a 13.08 starter gear, corrected to a 24" tire. I get that.
And the 4.10s with the 3.09 make an 11.26 starter-gear,corrected to a 27" tire.
So I get how this could be useful in your case
 
My goal is to obtain a low enough gear to putter around in 1st without the car jumping everytime a spark plug fires....
 
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