727 in an F Body

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CM360

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I've pulled a number of 904's from V8 F body. Will the 727 fit ? Driveshaft will need to be shortened. 904 transmount ? Tunnel clearance? Will opt for after market shifter and valve body. Looking to make my SW my tow car.
 
CM360:

If you are going to change the tranny and shorten the drive shaft, you may want to consider putting in an A518 (Overdrive 727). Bell housing pattern is the same as a small block A727, and you will still need to shorten the drive shaft, but the tranny mound has to be moved back between 1-2 inches and made deeper by about 1 ", and you may need to work out the speedometer cable and TV cable lengths, but you gain am overdrive gear and lockup torque converter for the highway. Just a suggestion. For the towing specifically, you can go to a lower rear gear, and not have it beat you up on the highway. As an example, go to a 3.55:1 rear end gear, and have an effective 2.45:1 on the highway.

Kostas
 
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A 727 will fit just fine,
I just changed my 904 to a 727 in my 80 M Coupe.
Which is the same setup as a F.
727+In+80+Lebaron+Coupe+002.jpg


727+In+80+Lebaron+Coupe+002.jpg
 
We are doing a similar conversion for my budy's F wagon. We got a 46RH, otherwise known as a 518. Note: a 46 RE is the 1996 and newer one and electronically controlled. The one we are using came out of a 1990 1 ton van. The controls require some vacuum switches. This trans is also a non lockup- apparently they are out there as well. We could not find a non computer / lock up type trans. One thing to keep in mind is a trans cooler- bigger the better if towing. Final note: I don't recommend towing in overdrive on a stock OD trans. Good luck either way you go.
 
Slant5Billy:

Good points, forgot about therm. There is a fairly cheap kit (<$100) from PATC that has all the vacuum and toggle switches for the electrical side. One of them is used to enable/disable the OD, and the other controls lock up of the torque converter.

The lock-up torque converter type transmissions have a 3 pin connector, the non-lock up type have a 2 pin connector.

There is an article here:

http://www.transmissioncenter.net/SwapInformation.htm

There are definitely other ways of doing this, and you can get your own parts and come up with the same, or even a better system, but this is a good overview on what is needed.

Kostas
 
You're gonna need beer, sawzall, and a mig welder for a 500/518 swap. Trans tunnel and structural trans crossmember fabrication required....
 
I dont think a OD coversion is worth tearing up a nice solid floor of a Classic.
if its all rusted out and needs replaced anyway, then ok.
 
CM360 said:
I've pulled a number of 904's from V8 F body. Will the 727 fit ? Driveshaft will need to be shortened. 904 transmount ? Tunnel clearance? Will opt for after market shifter and valve body. Looking to make my SW my tow car.
Click to expand...

Is this for your Stock class car? If so, stay with a 904. All else equal, a 904 will be about .15 faster than a 727. Chrysler did a lot of testing back in the mid-'70's and found that out. Low 2.74 low gear sets are also available in '80's 904's that can be used while the lock-up stuff is eliminated. I don't know the details, just let my trans guy do it..
 
F bodies could be had with a 727 (my Aspen A38 came with one) so yes, as others have mentioned, will fit with a shortening of the driveshaft.

Remember, there is one bracket piece that is different on the 727 than the 904. I've heard of it referred to as a pivot bracket. Everything else should be the same. Some others can probably tell you more about the bracket you'll need.
 
While the driveshaft needs to be shortened to compensate for the longer 727, did anyone mention that the slip spline yoke needs to be changed because 727 & 904 are different?
 
The throttle-pressure (kickdown) linkage is the same. The only difference there is up top, 2V or 4V carb. The 727 and 904 use the same valve body, and it's the same distance from the back of the block.

The 2.77 gearset will not directly fit a 727. The 727 drum needs to be machined, then the modified 998/999 gearset pressed into place and welded into it. It is a drop in for any 904, though, with no additional parts required. In virtually every case, though, lockup transmissions should be avoided like the plague. They have a different input spline so you can only use the failure-prone lockup converters, and those are definitely not something you want for race or tow duty.
 
The kickdown rod from the bell crank to the trans lever has a different length.
I understand the difference in a 2bbl to 4bbl, but cant figure out why the rods are different lengths between the bell crank and vb.
 
MiradaMegacab said:
The kickdown rod from the bell crank to the trans lever has a different length.
I understand the difference in a 2bbl to 4bbl, but cant figure out why the rods are different lengths between the bell crank and vb.
Click to expand...

I used the 904 rod with no problems.
Mines adjustable.
 
I've never run into the problem when converting from a 9-series to a 727, regardless of linkage style.
 
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