727 to 518 swap 73 charger

[randy73]

I did not take any pics yet, but I thought I list what I did. Mine was going behind a 73 340 in my charger. I would like to point out that I did not need to modify my tunnel in any way and I will also say my new RR floor pan sits 1/4" to high (sherman pan).

I got a 95 46RH already rebuilt and a rebuilt TC, make sure the TC has the 90 degree bolt pattern(96+ 46RE TC) and is weighted (73 340's are externally weighted, 72 and prior are not), I got a new speedo gear( be careful here, there are gear charts on the net that are totally wrong).

I got the $85 PATC kit to get overdrive and lockup - note: Their wiring chart on their website is wrong, use the 'NC' pin for the power wire to the tranny, not the 'NO' pin that shows in the chart,everything else is correct, except I used a ignition power source and not the battery. DO NOT forget to order the 3 pin connector.
I do not know about other year 727's, but my yoke would not work on the 46RH, got that from PATC also, BTW they are very helpful and answered all my questions, even when I asked the same one several times.

I used my old crossmember, I just cutout the old mount and used 1/4" steel to make the plate to mount the tranny mount too. I cut two 2 1/4" long by 6" plates, I put one inside the member and one underneath. Then made a 7" long by 6" plate, put that under the other 2 1/4" plate and welded the 2 plates to the cross member, then welded the one plate inside the cross member and for added security (and peace of mind), I drilled two 1/2" holes through the plates and cross member and put 2 grade 8 bolts in.

If you do not have a lift, I bought a tranny jack from harbor freight for $130, it went for 5 1/4" to 24" and worked really well, it is a little flimsy when it is low, but worked well when it got higher.

For the pressure switches, I got 1/8" copper fittings from home depot and this is what I got
1 - male/male 1/2"  extension
1 - male/male 2" ext
1 - male/male 4" ext
2 - female/female 90 degree elbows
1 - all female  T connector

Wrap plumbers tape around all male fittings, I wrapped the tape around 2 complete turns.
Put the 1/2" extension into the tranny (this allow clearance from the housing), then put one of the 90 degree elbows on, then the 4" connector, then the T connector, then the 2" extension and then the last elbow.
To get mine to work, I set mine on a 45 degree angle downward and towards the rear.

I had my driveshaft shortened by 3" and I think it was just about perfect.

I could not find a speedo housing o-ring, so I sealed it with RTV, I do not recommend this method, but it does work.

I have a center console, so when jacking the tranny up, be very careful not to shove the shifter rod up into the console.

With my tranny jack, I had to get my car 30" high from the ground to the frame rails.

Also, since mine took 2 weekends to do, I propped up the rear of the engine with a 2x4 cut to length and a 4" x 4" piece of plywood to protect my oil pan.

Most important of all, DO NOT FORGET to drain the tranny oil before dropping the tranny, I got oil ALL over my floor and that stuff is hard to clean up.

Instead of getting 3/8" metal lines, I used high pressure rubber lines and a heavy duty trans cooler and bypassed the radiator all together.

I used my old shifter brackets, the one that bolts to the tranny and holds the shifter rod in place, I just welded a bracket to the tranny and bolted the bracket to that.
My kickdown rod worked perfectly on my tranny, I have heard of others having problems.

Measuring the drive angle proved to be difficult, as my car seemed to have settled lower after I measured my old driveline. I used washers cut to look like a 'C', that way I could lower or raise the rear of the tranny without unbolting the mount.

I used a 92 GMC K1500 tranny mount, I cut off the two 2 studs and drilled holes to run bolts through, I then knocked out the center pin so I could put the bolts though and bolt the bracket to the tranny, then I got a 5 1/2" - 3/8" grade 8 bolt to mount the bracket back to the rest of the mount.

I would suggest dropping the exhaust system, I did not do mine and it was sometimes a pain to work around.

And you have to completely take off the torsion bar bracket.

I have not driven it yet, waiting on shop to put the lockup on.

I will post pics as soon as I have everything in place.