Best Sure Grip for Autocross

[HTMLmopars]

I'm looking to build an 8 3/4 to replace my tired 8 1/4 for my Valiant. The car is mostly a street car, but I'm doing upgrades with my local autocross chapter in mind, it's my best access to cheap racing so that's what I'm building the car for.

I'm looking at the differences between power lok, sure trac, yukon's limited slip, etc. I'm trying to be budget conscious, but it's an 8 3/4 going in to an a body, so I don't plan to rebuild it any time soon, so I want parts that I'm going to be happy with.

I'm just curious if there are things that make the different options better for one discipline of racing over another.

 

[halifaxhops]

@Mattax

 

[Darter6]

sure trac,

I knew a guy that auto crossed a B body. Wrote for magazines .He traveled all over racing it. He ran a Eaton True Trac

 

[dano]

Probably a Torsen helical.

Mopar 8 3/4" (8.75) Eaton Truetrac Differential

Mopar 8 3/4" (8.75) Helical Gear Sure-Grip ("Sure-Trac")

 

[HTMLmopars]

I was leaning towards a helical, but did some research and on some autocross forums people were complaining that their helical diff was letting the inside tire spin. That was Miatas but I couldn't find anyone that had posted this question for solid axle cars. Hoping that someone here will chime in with what works for them.

I saw a local listing for a good 8 3/4 center section with 3.23s and a power lok clutched diff for a good price so I'm trying to decide if I just buy that or build the open diff I've got