I've been reading through the old threads and I still have a question...

If I use the 6816, with the 1.75" bore, am I heading for any immediate issues if I keep the rest of the system stock? The rears tend to lock before the fronts, even with Hawk pads on the front.

Luke implies that the smaller 1.6?" bore would be better with the stock system (that I have now), but I may upgrade more in the future...

So, is the 1.75" bore caliper going to get me in trouble, what do I need to look out for?

Of course the 1.75" bore is $30 cheaper per side so that's a big motivator for me to go bigger. I'll figure out a parking brake later.

John

my recollection is that it has to do with the mechanical advantage of the stock brake pedal not being adequate for the larger bore pistons....resulting in a really hard pedal and a lot of force to get adequate pad pressure. The smaller diameter pistons are easier to move for a given pound of pedal pressure.

Hi John! I would go with the smaller bore, that is what I run with the stock rears. Are these for the older bolt pattern hubs? I have something in the works for the new radial mount caliper with dust seals, and some fancy rotors. Not sure if your looking for cheap street application or what

Hey Jordan, thanks for the info!
This is for trackday/hillclimb use.
Like Hutch(?), I have a problem with the rears locking when I hit them hard before the corner, especially cold.
More initial grip in the front would help, but front pads need some heat.

iirc, I'm using the stock ATE pads in the rear.
Maybe some MetalMasters, or similar would help by reducing rear grip??

I can't wait to see your radial caliper solution!

I'm going to hold on the brakes for now, I need to concentrate on the engine first. I may dig out my old 99T 4-speed trans and use that too.

The car has to be ready for SOC, so brakes are a bit down on the list, possibly as late as Maryhill/ORP (late Sept.).

You can play around with pad compound in the rears to keep them from locking up. I think a basic street pad is what i ended up with with the stock calipers on the rear.

I was making two custom rotor hats that would take the very common 11 and 11.75” rotors. It would be great if you could squeeze an 11.75 under a 15” wheel but that remains to be seen. The nice thing about the 11.75” ones is that they are 38$ shipped amazon prime and are a high quality casting.

I'm sure I could be convinced to order a set of 16" wheels if you need a guinea pig...

Well I'm pretty positive they would work with 16"s but 15"s are in question. The radial mount calipers are slightly slimmer, I don't think the lug mount ones would fit 15s for sure unless you had a pretty good size offset. But when they are ready I'll keep you posted. Squaring away new production for T5 kits first and some other odds and ends, but they are next on the list