hey. my question is. i am building a supercharged a14 in a 1200 ute 1980. it ill only be used for street. should i spend the money on getting a r31 diff or commodore diff. or is my diff strong enough and i could just weld it.
and does my stock diff have adjustable centres. and if it does where could i find one
cheers

The H165 used on a 1980 ute I would think should be plenty strong enough. If you weld it it is more likely to break an axle or something. Why weld it?

What do you mean by adjustable centers?

ike u no how some u can adjust the ratios and centres adn sum u cant. is mine like that and do i got the same diff as u

No production automobile has adjustable diff gear ratios. Some race cars have a "quick change" diff, just remove a cover swap the gears and bolt the cover back on.

Yes, I have a 1200 ute H165 diff. This is a type where the entire center (Gear Carrier/Pumpkin) can be unbolted and a new assembly bolted in. So it's not difficult to change gear ratios.

The R31 I think is a Salisbury type. Salisbury type requires total disassembly to change gear ratios.

You weld the diff, you are likely to break it.

weld'd diff's brake ? i beg to differ

Yes, you are right. Welding the spider gears if done properly won't break anything.

Now if the diff is marginal for the torque output of your engine, then a spooled or welded diff can push it over the edge. Just like slicks will. With the H145 & H150 you are more likely to break and axle when the diff is welded -- if you have a high-torque engine.

Certainly for Antarctica you need a locked differential.

Antarctica hehehe

haha not just antarctica, a locked diff will completely change the behavior of the car making it much more predictable sideways, exiting corners etc. .... that is unless you're not used to it and can't drive, then it could tend to snap out and understeer into corners etc.

nicly said :)