Drag Pak Challenger TH400

[66Satellite47]

Does any know why the TH400 is the superior choice? What are the advantages?

 

[Budnicks]

I can't say 100% as to their exact reasoning
BUT;
IMO much better/stronger aftermarket cases available
they don't have to make or tool up for MoPar to source/produce them
(extremely costly to tool up & big $$'s in engineering, to produce something in small quantities,
for the limited MoPar markets)
cases especially that can handle the 1500+hp
much more readily available parts,
different low gear clusters/planetary gears etc.
better parts, stronger inputs & output shafts, drums, bands, friction materials etc.
Edited; also a sprag/overrunning clutch, that won't grenade as easily
& in far more quantity
& a much more affordable priced parts
(there's far more Aftermarket GM based stuff, made across the spectrum for racing, Than MoPar)
I'm sure budget/cost/bottom lines, has something to do with it too

you'd think MoPar SRT etc. that they'd make a better case for the TF 727
market & sell them too, win win, but it seems they don't/won't

such is life in the MoPar world
when it costs another $5,000 on a $100,000 car that's 5% lost profit
or it'd be added to the other end
to an already rare/select few in the market place to begin with
that buy these types of Factory &/or even these types/styles of racecars

it comes down to $$$'s & good Sense (not cents) IMO

 

[Jerry Hall]

I have never worked on a TH400 or a 440/6 or Hemi automatic. I helped a friend in 69-70 with his 6 pack Superbee automatic. There was also a 70 LS6 Chevelle in the same shop. The things I saw every few weeks were transmission work on the Superbee and valve train/motor work on the Chevelle. Both cars were equally fast when working. I saw the Chevelle beat the Bee due to transmission failure on more than one occasion. On the other side the, I saw the Bee win over the Chevelle on several occasions due to engine/valve train failure. When both could compete a pass the winner was usually driver related.

 

[kramer]

As far as shift qualities without much effort the TH400 is tough to beat, you can make the 727 shift pretty well but sometimes for the inexperienced it might take some time to get the right combo of parts to achieve that. Otherwise the 727 is a pretty solid transmission that can take alot of abuse.

 

[33 IMP]

I would be nervous with my feet next to a 727 with 1000hp in front of it.
There are Rossler th400s out there, converted to two speeds, behind 3500+ hp. The guys running three's in the eighth with twin turbo hemis all use th400s or glides.

 

[66Satellite47]

I can't say 100% as to their exact reasoning
BUT;
IMO much better/stronger aftermarket cases available
they don't have to make or tool up for MoPar to source/produce them
(extremely costly to tool up & big $$'s in engineering, to produce something in small quantities,
for the limited MoPar markets)
cases especially that can handle the 1500+hp
much more readily available parts,
different low gear clusters/planetary gears etc.
better parts, stronger inputs & output shafts, drums, bands, friction materials etc.
& in far more quantity
& a much more affordable priced parts
(there's far more Aftermarket GM based stuff, made across the spectrum for racing, Than MoPar)
I'm sure budget/cost/bottom lines, has something to do with it too

you'd think MoPar SRT etc. that they'd make a better case for the TF 727
market & sell them too, win win, but it seems they don't/won't

such is life in the MoPar world
when it costs another $5,000 on a $100,000 car that's 5% lost profit
or it'd be added to the other end
to an already rare/select few in the market place to begin with
that buy these types of Factory &/or even these types/styles of racecars

it comes down to $$$'s & good Sense (not cents) IMO

Budnicks, sure understand your point why Mopar would use the available aftermarket TH400, since an SFI case is there. GM aftermarket always does have that numerical advantage for sales. Seems like there would be a fair demand for an SFI capable 727 case. And seems like all the aftermarket 727 parts have the strength required to handle well over 1000 HP.

 

[66Satellite47]

As far as shift qualities without much effort the TH400 is tough to beat, you can make the 727 shift pretty well but sometimes for the inexperienced it might take some time to get the right combo of parts to achieve that. Otherwise the 727 is a pretty solid transmission that can take alot of abuse.

Parts combinations for 727 are well known by those that do 727's. Key is not using the wrong 727 for the wrong application. I suspect same for TH400. Don't think they're all the same either.

 

[66Satellite47]

I have never worked on a TH400 or a 440/6 or Hemi automatic. I helped a friend in 69-70 with his 6 pack Superbee automatic. There was also a 70 LS6 Chevelle in the same shop. The things I saw every few weeks were transmission work on the Superbee and valve train/motor work on the Chevelle. Both cars were equally fast when working. I saw the Chevelle beat the Bee due to transmission failure on more than one occasion. On the other side the, I saw the Bee win over the Chevelle on several occasions due to engine/valve train failure. When both could compete a pass the winner was usually driver related.

I have a fair amount of 727 experience. One thing I was really stuck by when helping my Chev racing buddy on his TH400, was how many more parts there were & what seemed like a lot of complexity compared to a 727. Parts looked to be as beefy/HD as a 727, just more to set up. Also worked on his Glides with him, amazingly simple but small parts.

 

[Darter6]

I'm almost sure I'm wrong, but I kinda remember that a Turbo 400 doesn't have bands ? Like I said I may be wrong.

 

[Demonic]

Seems like there would be a fair demand for an SFI capable 727 case.

You would think. A question for A&A trans or someone similar. My guess is there isn't enough demand.

 

[theman440]

GM never used the TH400 behind their diesel pickups - Chrysler did . . . nuff said!

 

[66Satellite47]

GM never used the TH400 behind their diesel pickups - Chrysler did . . . nuff said!

Chrysler used a TH400 in their diesels?

 

[theman440]

Chrysler used a TH400 in their diesels?

Clarification - GM did not, in their modern stuff anyway.

 

[BB BELLA]

pretty sure the 400 was used behind the 6.2 diesel, cucv pickup and early hummer until 4l80 and 6.5 became available!

 

[dvw]

I've seen the TH 400s used in the Drag Pac cars, (Ford, GM, Dodge). They are very trick with very few stock parts. The non supercharged cars are still using 904 based stuff.
Doug

 

[66Satellite47]

The 904 will work great with enough aftermarket parts. Still not equal to a 727 with the same level of aftermarket parts. Just less rotating mass.

 

[dvw]

The 904 stuff lives fine. Buddy runs 2 cars with them. New style Challengers, one stock eliminator (9.30 ), one in S/S (9.00). Both are close to 3400lbs.
Doug

 

[66Satellite47]

Great, you made my point. If you have the correct parts they do the job.

 

[vintage chromoly]

The one I looked at had a Ford 9” rear axle as well.
Of course, it was all aftermarket, but 9” architecture, no less.