Which drag racing tranny for street/strip?

12v Ford

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I'm getting ideas for a street/strip full size OBS ford truck with a 12v cummins used for drag racing and fun. HP will go up as money allows, so the tranny is expected to be fully built.

Standard trannys are out (too slow).

Gasser trannys are probalby out too because of the weight of the truck and torque. Lenco's and liberties are mostly full time racing trannies, so I'd have to say they're out.

The allison doesn't seem to be the cure because of the defuel on shift problems. The 5r110 is prone to breaking from what I hear.

So that leaves the 47re/48re, e4od/4r100, and the new dodge 6 speed(68rfe and Aisin).

Anyone have a suggestion for what tranny will last the longest and be the strongest? I don't think the dogde 6 speed has many parts available yet and it's probably not proven, but it would be cool if it will hold the same power as the four speeds.

How do the 4r100 and 48re compare? If suggesting the dodge 47 and 48's, which one is better?

Thanks,

Clayton
 
Easy choice. 47RH. No computer required, very simple & reliable, LOTS of performance parts available.
 
I think I would choose a full billet goerend 47rh with a manual valve body. Depending on the size of charger(s) a little higher stall torque converter. Billet flex plate. That should treat you right.
 
This may have changed but the last time I spoke to Dave I believe he said that it was a toss up on wither or not to put a billet intermediate shaft in it and that he was not confident in the billet outputs for the 47rh.
 
47RE with the PCS control unit and VB from SunCoast, awesome tunability for all conditions
 
Call up Toxic Diesel.. They are currently building me a full billet 48re, including billet drum an all the goodies, billet output shaft the same size and spline count as the nv5600, manual valve body, etc.. Should be very streetable and with enough strength to stand up to sled pulling and drag racing..!
 
So far, it looks like the majority is picking the 47rh. I'm probably going to go with Suncoast for the tranny. Once I get some bucks together, I'll call suncoast and go with what they recommend.

Would I still need to use a PCS controller for the 47rh? I don't know much about automatics. Standard trannies are more my thing, their either in gear or not, and it's up to me what gear I want:evil.

What are the big boys like Smith, Stucky, Spruill, ect using?
 
This may have changed but the last time I spoke to Dave I believe he said that it was a toss up on wither or not to put a billet intermediate shaft in it and that he was not confident in the billet outputs for the 47rh.

I thought the 47rh had a larger output than the 47/48re? So a lot of guys for drag racing where running stock outputs... That true?
 
Give Jeff Garmon a call too...after watching what he's doing nowdays....he should be a contender when your final decision is made.
 
buddy of mine put a 4R100 behind a cummins and its goin great for him

Engine has sled pull 66,DV's, 370's, +pump mods, studs etc.
Tranny has roadrunner converter and basic performance rebuild

After looking at the tail housings the 4R100 seems bigger and with the electronic module controlling it he can change his shift points whenever and i think the total bill was around $2500

just food for thought...
 
$2500 seems too cheap for a built 4r100. Especially since a PCS controller is like $800. I would go with the 47rh. The 4r100's work great but going with the dodge trans saves you the cost of buying an adapter plate.
 
Opie has a new techniquie with the intermediate shaft that supposedly makes it stronger in the 47rh. Darren morrison ordered mine for me and I have the new shaft. I dont have any serious horsepower yet but i thought i would mention that. Maybe you should try to call Opie
 
No disrespect to any tranny builders out there. I have yet to make it to the track with my new tranny, but it feels very good. The shifts are very quick.. The 2-3 shift is very impressive.. Under normal drive there is no clunking as it downshifts or anything else unusual.. It's like driving a stock tranny under light throttle. Under heavy throttle I can easily tell a difference in this tranny.. I won't mention the other tranny suppliers names, but they are big name reputable shops.

My current tranny is a complete 47RH Garmon unit with a Suncoast converter. I call it my Whoop Azz tranny.. It's a true daily driver that will pull mid to low 11's on diesel only and still pull a trailer..
 
Garmon is also now using Opie shafts.. I already had the input, but I went with the Opie intermediate..
 
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