Overdrive options

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WCMachine

WCMachine

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i have a prostreet duster, 340 ,reverse shift 727 transmission and 33" MT's. The 9" ford has 4:86 gears. I'm turning around 3500 at @60. This is making it painfull to travel any distance on the interstate.
I'd like to keep the gearing, so I'm considering an overdrive. I've looked at the gear vendors but maybe you guys have other suggestions.
 
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The GM 200 is a good choice.
 
WCMachine said:
Thanks, Do you know what's involved in making the swap?
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An adapter kit of course. A few companies make them. Wilcap would probably be my first choice. Don;t let anyone tell you the 200 is weak, blah blah. GM put that transmission behind the 3.8L Turbo Buicks of the 1980. You know, the cars you could add a chip and slick to and run 10s? Yeah. Those. The ratios are really close, too. Yes, you have to build them to performance specs, but the cost is still cheaper than a comparable Chrysler OD, plus you don't have to hack the floor or cross member up. A custom drive shaft is required of course. Big deal, right?
 
RustyRatRod said:
An adapter kit of course. A few companies make them. Wilcap would probably be my first choice. Don;t let anyone tell you the 200 is weak, blah blah. GM put that transmission behind the 3.8L Turbo Buicks of the 1980. You know, the cars you could add a chip and slick to and run 10s? Yeah. Those. The ratios are really close, too. Yes, you have to build them to performance specs, but the cost is still cheaper than a comparable Chrysler OD, plus you don't have to hack the floor or cross member up. A custom drive shaft is required of course. Big deal, right?
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I've put a few behind some healthy 572 Chevy crate motors. They'll hang if built right. I'll add that you have to get that TV cable geometry and adjustment right.
 
518...46RH
builds like a 727...with od in the tailhousing.
bolts right up to the small block.
get the year with three pin connector if you want lock-up tq, 2 pin just od.
Theres a 904 version too...just dont recall the #.

I have a 518 (ok, 3 of them:D) thats going behind a warm 360 in my Aspen wagon, 8.75 with 4.10's.
 
Jimacuda said:
518...46RH
builds like a 727...with od in the tailhousing.
bolts right up to the small block.
get the year with three pin connector if you want lock-up tq, 2 pin just od.
Theres a 904 version too...just dont recall the #.

I have a 518 (ok, 3 of them:D) thats going behind a warm 360 in my Aspen wagon, 8.75 with 4.10's.
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I'm going with the 46RH in my Valiant, but there is going to have to be some reworking of the T-bar/trans crossmember above the trans. With the 200r4, you just need to build a new crossmember and fold the pinchweld at the firewall.
 
GVOD.

4.56 gears and I run about 2500@60mph.

I've had the GVOD for 15 years or so. It works flawlessly and would also work with your 727 which is a nice bonus.
 
roccodart440 said:
GVOD.

4.56 gears and I run about 2500@60mph.

I've had the GVOD for 15 years or so. It works flawlessly and would also work with your 727 which is a nice bonus.
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Does the driveshaft angle become a problem w/ the gearvenders on a 727 in a 68 fish ? Looks like the d.s. would be extremely short > Wish I could afford one.
 
The problem I see with a DIY 200 is just getting a transmission PERIOD!! Can someone enlighten me on what all they came in? Seems like "not much"

Someone mentioned a 904 series OD. A500, 42/ 44 RH or RE. You can buy an all manual VB or Transgo kit all manual for the A518, not sure if it will work in a A500
 
famous bob said:
Does the driveshaft angle become a problem w/ the gearvenders on a 727 in a 68 fish ? Looks like the d.s. would be extremely short > Wish I could afford one.
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I know it's not everyone's first choice but I have a 999/GV setup in my 67 Notch and it performs flawlessly. 3:73-1 SG with 28" tall tires = 2400 RPM @ 70 MPH.
I like it!
 
I just spent a drag week driving around with a bunch of guys with gear vendors... now I want one. And there are cars with way shorter drive shafts than ours running them.
 
Turbo HydraMatic 200–4R. I pulled one out of a 85 Fleetwood Bro-ham, but changed gears and went with a A-500 from a Dakota. Pun intended, info link.
Turbo-Hydramatic - Wikipedia
I think the manual valve body will work on the 500, the trick is a reverse pattern manual.
 
famous bob said:
Does the driveshaft angle become a problem w/ the gearvenders on a 727 in a 68 fish ? Looks like the d.s. would be extremely short > Wish I could afford one.
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No issue with the driveshaft. You remove your tailshaft and the GVOD replaces it. Your driveshaft gets a little shorter than stock but nothing crazy. It's probably beneficial.

67autocross said:
I just spent a drag week driving around with a bunch of guys with gear vendors... now I want one. And there are cars with way shorter drive shafts than ours running them.
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There is a reason Drag week is sponsored by GVOD. They work and they sell themselves.
 
roccodart440 said:
No issue with the driveshaft. You remove your tailshaft and the GVOD replaces it. Your driveshaft gets a little shorter than stock but nothing crazy. It's probably beneficial.



There is a reason Drag week is sponsored by GVOD. They work and they sell themselves.
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cool. thanks. I will have to have a "deal" to be able to afford one tho.
 
Anything other then a gear vendors you'll have to hack the tb crossmember to make it fit.

Gear vendors doesnt have as good a od ratio as the full od transmissions but are supposed to be strong and other then a dent require no surgery to the floor it tb crossmember.
 
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abodyjoe said:
Anything other then a grear vendors you'll have to hack the tb crossmember to make it fit.

Gear vendors don't have as good a od ratio as the full od transmissions but are supposed to be strong and other then a dent require no surgery to the floor it tb crossmember.
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The 200R4 and 4L60E conversions don't need hacking.
 
cutaway-upper-crossmember-2-jpg.jpg


Sure looks like you have to hack up that crossmember to me. Some guys are ok with that. Some won't want to do that.
 
abodyjoe said:
Anything other then a grear vendors you'll have to hack the tb crossmember to make it fit.

Gear vendors don't have as good a od ratio as the full od transmissions but are supposed to be strong and other then a dent require no surgery to the floor it tb crossmember.
Click to expand...


I'm not sure what the others offer but it drops the .78 to 1 ratio of the GVOD unit is lifechanging. I mean, the first time you run 4.56's down the interstate your mindset on everything changes. You'll never be without an OD again.
 
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