I'm building a 69 Dart SL6 racer. I want to change the 7 1/4 out to
an A body 8 3/4 741 open 3.91 unit.
Because I will be adding nitrous and want it to hook up,
can I "add" a sure grip to the "pig" and if so
what should I look for.

Understand there were 2 different types of sure grips.
I know the 741 was the weakest 8 3/4 but even tho I'll have
nitrous the car will go 12's max if I'm lucky.

Rick

A 741 will survive just fine. There are no "weak" 8-3/4" centre sections. There's "strong", "real strong", and "unbelievably strong".

Two sure-grip styles, and yes, SG can be added to any 8-3/4" centre chunk: Clutch type or cone type. Each has its benefits and drawbacks, so I'll step back and let those opinions be stated.

Here comes my opinion. Either sure grip unit will work fine, if it is in good condition. The clutch type is easier to repair/rebuild. I have heard the "cone" type can be repaired, also, but not easily. If this will be a drag race only car, you could consider a "mini-locker". The unit just replaces the spider gears, and is less the $100 from Jegs. Don't use it on a street driver.

_________________
Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225