I recently upgraded the engine in my old BlacRay and even though I breathed some new life into the 350 turbo it isn't enough. I want more out of the transmission, so I am wanting to upgrade it to a 700R. This is where your talents come into play. Can I get some help from those who have done this in C3's from 68 to 79? In particular I am interested in the following:

Crossmember Movement Information-

Rear Mount Information -

Purchased Crossmember Companies -

Shifter Information

Exhaust Information -

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From what I have read it appears that I can move the existing crossmembers front bolt pattern to the rear holes and drill out new rear holes in the frame to attach the crossmember.  I think the mount can be cut down to fit as well.

I am leaning to buying a purchased crossmember that should have the rear mount with it if I can. I would like to do as little changes with my exhaust as possible since it is new from the headers to the mufflers. In saying that I know that I will be doing some.

With the swap can the OEM shifter be utilized? That would be nice so that I don't have to fabricate something to work with the heater controls.

I do recognize I will need to cut the driveshaft down approximately 3".

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So, with all this being said I thought I would ask the experts here and hope that someone chimes in with some good advice. Thanks in advance for your help... 

Tux,,,

Tuxblacray: She's Back In Black! Check out my pics @ My Link


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I replaced my 1973 TH400 with a 200R4

everything you need can be purchased from some of the after market trans companies 

I bought mine from Bowtieoverdrives.com

you doubt need to buy their transmission but they will help you with everything you need for the install. Some people say you can file your shifter detect plate to work but I recommend you purchase the plates and install them on your shifter.

you should replace the crossmember with one of the ones made to fit the 700. The 200R4 can use the stock one by the location of the mount on the 700 is quite a bit further back. Changing yo an OD trans is a great update

good luck

Brian - NCM Lifetime Member

73 coupe L48, Flat-top pistons, Performer RPM Heads, Crane Cam and roller rockers, Holley 650 vac sec. Performer intake,
3.55 gear BTO 200-4R trans,
Leather seats, Seatbelt Plus 3point seatbelts, Pioneer CD player
Magnaflow Exhuast System

Brian,

Thanks for your suggestions! I plan on buying a 90 - 91 700R4 core and having it built to pair nicely with the new 390 HP BluePrint crate engine. Thanks for the info on Bowtieoverdrives.com. I had them earmarked to check out having read much on this. As for the shifter I believe I can make the stock one work out by moving the cable mount on the pan to accommodate another gear. In the console I will utilize a 4 speed center and go to a leather boot.

Good to hear from you after many years! I hope your doing well, and thanks again!!!

Tux...

Tuxblacray: She's Back In Black! Check out my pics @ My Link


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