Any LowBuck but STRONG overdrive option?

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GM 200R4 or a FORD AOD. I think both have been used with only a crossmember mod to fit and a plate or bellhousing. IIRC the tunnel was OK with maybe 1 dent to clear some bump. An electric lock up will give you about a ~250 RPM reduction at speed.
 
Funny you mentioned the Ford AOD. I do know a guy that did that behind his SBM. I don’t know what mods were done/needed. But he does like it very much.
 
if you swap in the A998/999 ratio box with a lock-up, the new low gear of 2.74 is 11.8% lower than the 2.45 of the 727. This would allow you to drop that same 11.8% out of the back.
Post #1 says you have 4.10s so, now yur down to 3.55s.
Ok 4.10 x 2.45=10.05, and 3.55 x 2.74=9.73; close enough..
Now for second gear; your current combo is
4.10 x 1.45=5.945, and with the other it would be
3.55 x 1.54=5.467, that's doable.
Your current combo with 27inch tires will do 65=3350 at zero-slip, possibly as high as 3500 at 4% but more likely, 3450 at 2.5% slip on flat level,hard ground.
The new combo will get you 65= 2900 in lock-up. that is a total reduction of about 16%.

The Mopar overdrive unit has a ratio of .69, which is a reduction of 1 minus .69=.31 or 31%; and that would bring your current 65=3450@2.5% slip, .. to
65=2311 in lock-up.

Will the A998/999 trans take 400hp?
With a few affordable mods, yes.
Except for requiring a longer driveshaft with a 904 yoke, a different flex-plate, and all the original KD mechanism, this is a bolt in.

credit to RRR for first mention in post #9
 
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Bodyperson said:
Getting a little off track here RRR as this is far from a "low buck" option. @Treblig is running one too I believe. Sure, you need a mount modification but the body fits. The Mopar overdrives need the body modification.
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I didn't bring the damned 200 up. I'm right on track because I reminded them the 200 requires cutting which is NOT budget friendly. Next.
 

Yeah and you clearly said it would not require cutting.....said you ran one. So what is the argument?
 
Bodyperson said:
F

Like others have said. I think it can go both ways. A lot of modifications to the transmission to make it fit without modifying the body. Seems easier to me to just modify the car.
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It's just tight as a virgin on prom night no matter what you do. I think even modifying the cross member on a stock vehicle with a 904 would have it's advantages.
 
Bodyperson said:
I didnt say I run one. Just did some reading about it. I guess that makes me a "poser"
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LOL. Then I guess I am too cause I ain't got a 600 cube Hemi and a 200r4. We'll be posers together. LMAO
 
RustyRatRod said:
It's just tight as a virgin on prom night no matter what you do. I think even modifying the cross member on a stock vehicle with a 904 would have it's advantages.
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While it's apart, I actually think about doing it to my Barracuda for a future upgrade. It aint quite that rotten but it does need front floor boards.
 
Ironracer said:
That's what I figured. I don't have the numbers on the thing but he told me it's a lock up 727. I'm probably confused cuz I read something about being able to take a lock up converter Indo power to it but that was probably for the overdrive 500 or 518
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There is a hydraulic lock up 727 non overdrive.
Easy to spot just pull the torque converter the lock up model uses a different input shaft. The lock up shaft has no splines on it for the approximately the first inch the non lock shaft will have full splines.
I am having one built for my Barracuda later this year, trans Guy just found a core for the project. Should not require any major metal work to install. We will know more after I get my hands on the core.
 
512Stroker said:
There is a hydraulic lock up 727 non overdrive.
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Yes but the ratios are still 2.45-1.45-1.00; so about the best rpm reduction you can get will be 2 to 4% depending on cruise rpm and power required to push your vehicle thru the air. With 4.10s, Ima thinking closer to 2%, on account of the rpm.


BTW;
I wouldn't recommend the 3+1, A833; the od gear has only about 18/20 teeth on it and is, in my experience, easily shattered. Even my stock long-block 1973 smoggerteen blew one up when I put a lil too much power into it. My 367 blew two more up.
That overdrive is strictly for cruising in;
it will not survive any shock-loading.
 
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Though simple enough to spell, Good and Cheap are Two words that don't often fit together very well.

Cheap is also a relative word...One man's Dollar is another's Hundred.

Personally, I'd get one of these NEW Ready to Go Proven Performers that'll fit your specific Tranny/Engine combo and be done with it rather than dicking around for God-knows how long trying to Sav-A-Buk when you'll ultimately end up probably spending the same amount and having an inferior product....

Just My Two Cents and that and another $23.98 will get ya a cup of Starbuckles.

Automatic 3-Speed 727 18" Tailhousing - Gearvendors

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Expensive as heck option but it ma suite the need.
Thanks can not justify that insane expense for MY purposes.
 
AJ, I am OK with the trans ratio's as that is what I currently have with my non lock up 727. My current 727 is gett'n tired and as long as I have to replace it I figured that I would spend the money for a lock up 727 and converter.
442 HP, 340, 3000 stall, 3:55 ratio with 28 in tires.
With the lock up Im guessing the my engine rpm @ 60 mph will be around 2600 rpm.
Your thoughts?
Sorry to step on the thread.
 
20180813_152535.jpg

Here's what I had to cut to get the 200-4R to fit in my 73 Sport.
 
i'm with AJ...904 with low first and second gear.With that hp in an A body you should be able to run
a 3.23 rear gear which will be the same as 3.6:1 in first but final drive is 3.23.
The fly in the ointment would be if you had a long duration cam which would kill lo rpm torque.
What cam are you running?
 
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