Drove my 1980 home today

[pantera928]

Well, I drove my 1980 home to Georgia from Cincinnati today. 500 miles. No issues but 3000 RPM at 70 MPH seems high. Looking to get that RPM down.

Everything on the car working great except the clock.

[Avanti83]

Because it's SBC powered it probably has a TH350/400 trans in it. If so, a 700R4/4L60 or 2004R (overdrive units) should knock about 8/900 rpm off it. My 83 came with a 700R4 OEM.

You would need to add a TV cable, modify the rear trans mount (move) and shorten the drive shaft.

[pantera928]

7 hours ago, Avanti83 said:

Because it's SBC powered it probably has a TH350/400 trans in it. If so, a 700R4/4L60 or 2004R (overdrive units) should knock about 8/900 rpm off it. My 83 came with a 700R4 OEM.

You would need to add a TV cable, modify the rear trans mount (move) and shorten the drive shaft.

I was told by another owner that the 200-4R would drop right in without and mods to the drive shaft. Anyone?

 

TV cable??

[Desert Driver]

8 hours ago, Avanti83 said:

Because it's SBC powered it probably has a TH350/400 trans in it. If so, a 700R4/4L60 or 2004R (overdrive units) should knock about 8/900 rpm off it. My 83 came with a 700R4 OEM.

You would need to add a TV cable, modify the rear trans mount (move) and shorten the drive shaft.

All of that is correct. Took out my Borg Warner automatic boat anchor and went with a 700R. At 70mph I'm doing about 2100 RPM..a lot more civilized!

[Avanti83]

Here's the reported dimensions of the GM trannys in question. I'll let you decide drive shaft length.

http://www.vintermossen.se/cheva/transmissions.htm

[wildfelr]

RQB3263 1981/305      yes had the same situation on 3263...installed 700R4  four yrs ago with exactly  the same mods detailed in this thread..... the trans mount was easy (pics) the TV cable is very important, if now correctly adjusted will do serious damage to trans... with my  original 2.72 rear gear im tacking 1750 at 65 MPH....PERFECT.....

[Dwight FitzSimons]

Wildfeir,

I think you mean "if not correctly adjusted...", not "if now correctly adjusted".  Right?

--Dwight

[pantera928]

So am I correct in assuming that the 1981 and up cars with a 305 and an th400-4R used a different drive shaft than the earlier cars with the 350 and 5400 transmissions?

What does this TV cable do?