I have already done a C5 brake conversion on my 94 z28. My question is, does anyone know the piston size in the master cyl on 1998-up f-body?
I am pretty sure that 93-97 have a 1" bore, and I am curious if I need to swap the master cyl to get everything right for the dual piston calipers.
Thanks
Stevie

 

Anyone?

 

Not sure if the LS1 MC is different but I have have no problems with my LS1 capilers with C5 rotors. Only other change I made was to remove the stock proportioning valve and install an adjustable one.

 

You don't need to make any changes with the master cylinder or prop valve for the C5 setup.

Dan

 

I had considered putting an adjustable valve in it also, I have a problem with locking up the fronts now. Especially since the abs is gone.
Thanks

 

Hmm, that's interesting. I have a few questions though:

Do you have the same type of pads on the front and rear?
Do you have the same type of rotor front and rear?(blanks, slotted, or drilled)
Do you have the same size and type of tire in the front and rear?

You may not need a prop valve depending on your setup.

Dan

 

Hawk HPS up front, some advance crap out back
solid rotors front and rear, c5 fronts, lt1 stock rears
tires 275-40-17 Kumho's all around

It wants to slide the fronts in heavy braking which is why I thought about an adjustable valve.

 

I would look at putting in Hawk HPS pads in the rear and then see if it still does this. I'm almost certain that the autozone pads are not as agressive as the Hawks HPS pads. My C5 conversion doesn't seem to have the problem you mention. I have Hawk HPS on all 4 corners, blank rotors front and rear.

The only problem with just putting on the HPS pads in the rear is if the old pad material is bedded into your rear rotors, then you might want to replace the rotors too. I have cheap durastop? rotors from autozone in the rear with the Hawk HPS pads and they work great. I sprayed the center of the rotors with high temp ceramic black spray paint to keep them from rusting, and to keep them looking nice.

Dan

 

I may give the rear hawk pads a shot to see if it helps, makes sense.

 

i'm suprised that you're no longer interested in the diameter of the bore of the master cylinder of an ls1 f-body