by Smiley » Fri Apr 10, 2015 3:35 am
Unless you plan on doing a power tour I would just use a 3 speed auto for racing or cruising around town, they are cheap and simple.
71 Vega's will need some reshaping (BFH massaging) of the trans tunnel around the firewall for V8 transmissions.
1986 and up 700R4's are good.
700's are longer so the driveshaft will need to be shorter.
700's have a different rear mount location so the crossmember will need to be moved back more than 350's.
700's use an electric solenoid to activate the lockup, this will require a controller or at least some basic wiring and pressure switches.
700's and 200's use TV cables that look like the older passing gear cables but require very precise adjustment and that the OEM pivot to throttle shaft geometry be used.
So if you use a universal aftermarket performance carburetor you must add the cable pivot at the same location as a factory carb or throttle body and then adjust the TV cable tension to specs.
I swapped a TH350 for 86 700R4 to get overdrive and lockup and I did not like the 1st to 2nd RPM drop compared to the TH350.
I was driving 50 miles a day with about half on the highway so I recouped the time and money.
The 2004R trans has closer ratios from 1st to 2nd and shares most dimensions with the TH350 making it an easier swap.
A 3 speed TH350 with a 3.42, 3.23 or 3.08 works well with a healthy 350 V8 in an early Vega.
A 4.10 rear axle gear with the 3.08 first gear of the 700R4 will give way too much torque multiplication for a 24" street tire.
What do you plan to use the car for most of the time ?
Last edited by
Smiley on Sun Apr 12, 2015 6:53 am, edited 1 time in total.