Learn me: 4 speeds

Since this has been brought up a few times, which 4spd can handle roughly 475-500 whp/wtq of turbo 4.8L LR4 in a 3-3.5K car? The car will see very little hwy use

I have been reading all weekend on GMs and Fords 4spds.

The one's that jump out are

• Muncie
• Saginaw
• TopLoader
• T-10

From what I read, I should stay away from Saginaw and TopLoader overdrive transmissions. But with the asking rate of Munices and TopLoaders (around here), I'm only a couple hundred away from a T-56.

What say ye, oh wise GRM collective??

Muncie. Shouldn't be T-56 money though.... Watch for different gear ratios. m-21 vs. m-22. Maybe a Borgwarner T-10? Or is that the Top loader?

Whoops . . forgot to add the T-10.

Fixed . . .

In reply to Gearheadotaku:

Maybe I need to widen my search area. Most of the Munices I've found are in the 700-1K range with unknown histories

I seem to find the Saginaws and TopLoader ODs all over the place . . .for stupid cheap.

I've found an adapter for a chevy bellhousing to the AX15/R-154/NV3550. I was trying to find a torque rating and the R-154 seems to be about 400 ft-lb. It seems to be a cheaper alternative to a T-56 and is also stronger than a T-5.

Adapter Link

Edit: R-154 is from a Mk3(?) Supra. The other transmissions are more truck-like and probably exorbitant information.

ax15, R-154 what are these from?

edit:

I should read links before posting to avoid looking dumber than I already am....

Be careful with Saginaw and Top Loaders as they made a LOT of them that were not very high in torque rating. The 3-speed versions may even use the same case.

Personally, I'd go T-10 if you can find one. They're as strong as a Muncie, have a strong aftermarket, and were found in a lot of applications.

Your cheapest bet though is a stout automatic (727TF or a TH400) with a manual valvebody and a ratchet shifter...

T10 all the way.. specifically, a Super T10. the easiest place to find one would be in a late 70's Z/28 or Trans Am.

you can also still buy them brand new for something like $1500 with a few different ratio options, and they were the trans of choice at the super speedways in the top NASCAR series until about 5 years ago or so.

Super T-10 is your answer. There's a reason they were in every Nascar Racer for years

I know the R-154 may be able to handle it the tq, I doubtful of the AX-15 (haven't read enough to grant a verdict).

Supposedly (according to Mallet - think LS powered Solstice/Sky), the MA5/AR5 (based on the R-154) can handle that amount of power, but that's inconclusive . . .

Awesome . . .

I'll expand my search.

The C4 Corvette used a Super T-10 as the "4" part of 4+3. They often go for cheap with a dead O/D unit attached. The end of the case is different but may be used with some mods?

The Mopar A-833 gets talked about, especially the variant used in GM trucks; OD 4th gear and has an SBC bell housing / clutch arrangement as a factory application. 80's Silverado etc etc for a donor.

pres589 wrote: The Mopar A-833 gets talked about, especially the variant used in GM trucks; OD 4th gear and has an SBC bell housing / clutch arrangement as a factory application. 80's Silverado etc etc for a donor.

I have never put power down with one, but I DDed one in a truck for a while and loved every minute of it - took advantage of that 3.73 rear gear while maintaining reasonable cruise RPM, all with four gears - aluminum case, too.

In reply to tuna55:

I would think that there are Hemi/440 spec parts to rebuild one to take on the kind of power the OP is talking about since it's the same basic box. Seems like a pretty cool box. I also believe that there was a few small-block Ford factory applications of this gearbox although I could be mistaken.

pres589 wrote: In reply to tuna55: I would think that there are Hemi/440 spec parts to rebuild one to take on the kind of power the OP is talking about since it's the same basic box. Seems like a pretty cool box. I also believe that there was a few small-block Ford factory applications of this gearbox although I could be mistaken.

There was a place making hi-po aftermarket parts, something purple - can't remember - there was a Hot Rod/ Car Craft article - I'll dig it up.

In reply to tuna55:

http://www.passonperformance.com/

My buddy had a Super T10 in his Firebird that we beat on for years. We went through half a dozen or so Pontiac engines before building a killer 455 olds but never had any problems from the transmission so they get my vote.

pres589 wrote: In reply to tuna55: http://www.passonperformance.com/

That's it!

pres589 wrote: In reply to tuna55: I would think that there are Hemi/440 spec parts to rebuild one to take on the kind of power the OP is talking about since it's the same basic box. Seems like a pretty cool box. I also believe that there was a few small-block Ford factory applications of this gearbox although I could be mistaken.

Don't think Ford ever used the A-833...but it was news to me that Chevy trucks did.

You can get a Super T-10 from a 1980 or 1981 (not exactly sure which) with a super low 3.44:1 first gear.

It will make a car with 3.08 rear gears launch like it has 4:10s

Chevy used this to make the anemic 305 Z28 bearable to drive. It's the same one I used when I swapped my Turbo T/A to manual.

The only thing that sucks is the 2-3 gear spread is really wide and the boost drops off pretty bad.

Super T-10 > T-10

Warner seems to rate these transmissions pretty low as far as the torque they can handle, I've seen lots of them beaten but never broken.

Another thing to think about, I've found that the ST-10 doesn't shift as quickly as the T-56 transmissions, the gears are bigger and heavier in the ST-10 and take a bit more time to match speeds. This may be a concern if you're turbocharging.

Shawn

psteav wrote:

pres589 wrote: In reply to tuna55: I would think that there are Hemi/440 spec parts to rebuild one to take on the kind of power the OP is talking about since it's the same basic box. Seems like a pretty cool box. I also believe that there was a few small-block Ford factory applications of this gearbox although I could be mistaken.

Don't think Ford ever used the A-833...but it was news to me that Chevy trucks did.

Chevy used it in diesel applications, 6.2. Same bellhousing, I have one bolted to my 350 right now.

Strike_Zero wrote: I know the R-154 may be able to handle it the tq, I doubtful of the AX-15 (haven't read enough to grant a verdict). Supposedly (according to Mallet - think LS powered Solstice/Sky), the MA5/AR5 (based on the R-154) can handle that amount of power, but that's inconclusive . . .

R154s are pretty stout. That 400 lb/ft rating seems low to me.

I think I found a Super T-10. Awaiting the cast and stamped numbers to verify.

What is the going rate for these? I've seen prices all over the place.