C4 Front Disc Rotors - What type ?

Vettech · November 26, 2018, 06:28:04 PM

Was wondering about smallish upgrades when things wear out, for instance, disc rotors.
I see adds for Plain OEM types, T2 and T3, drilled, slotted etc etc. I cant see a definative explanation of the difference of T2 to T3 etc.

Has anyone ventured down this path, what type did you use, and was there a Results to $'s spent ratio of satisfaction.

I know one member has Willwoods or other on a C3, but has he gone over the top with mods to achieve what outcome.
I know my 78 went from catastrophic to great after the Calipers were machined, S/S sleeved, "O ringed" etc etc (it actually stopped then)

I only wonder because the wifes car stops on a dime, I wont mention the car. I'd like the C4 to stop like this.
C4's have vastly better std brakes than previous Vettes.

Regards.

sabre · November 26, 2018, 09:02:27 PM

Fitted 96 GS HD option to mine. Changes from 12" to 13" dia and 20mm to 28mm thick. Bolts on. Uses same pads. Bought DBA straight slotted (not drilled) rotors. Went from mediocre to excellent. Reduced pedal pressure and no fade. Good luck getting the calipers. They all want HD exchange.
Calipers cost me $500 and discs were about $220 from memory (which is failing). Suggest new braided hoses are a good idea too.

MY081 · November 26, 2018, 09:41:04 PM

I disagree Uncle Doug . C3s have 4 spot calipers and C$ have 2 spot ( I think ) Also slotted are best drilled tend to crack ( with hard work ) Also I am pretty shore the calipers on the C4 were designed and built in australia and there should be a holden equivalent . Also C3 s have 12 inch rotors ( just a tad under 12 ) In my opinion you can't go over the top with brakes Uncle Doug . Ray

sabre · November 27, 2018, 07:15:33 AM

Not getting into which is better but it depends what you define as "spot". C3 has 4 piston fixed calipers while C4 has 2 piston (on inside) floating calipers. True 4 spot have will have either 4 either side (fixed) or 4 on one side (floating).
You are correct about manufacture. The C4 and C5 (I believe) were made by Bendix Australia. Unfortunately GM have the company locked out with copyright so you can't purchase direct.
Re using Commodore parts, HSV use the same pads so there's a good range. The discs have a metric PCD and the centering hole is smaller on the Holden so they'd have to be machined. No point going down that road as the new discs are available locally (DBA) at the same price. I'm assuming no one is tight enough to use second hand discs.
As for the calipers, I'd be interested if any were interchangeable.

Vettech · November 27, 2018, 11:46:14 AM

Yes I thought they were out of Bendix Aust.

And Ray you are correct, no good having all the power in the world, if you cant stop.

A long ago friend was in the Brakes game, he had a Bendix book with life size pictures, you put your pad over the pics and if they matched, he ordered that Bendix number, I'm sorry now that we lost touch.

No one has commented on the meaning of T2 or T3. !?!?!?

bfit · November 27, 2018, 01:56:39 PM

T2/T3
I think the differences are
The T3 are a better design and a better quality casting for heat distribution.
T3 have heat indicators painted on as well.
T2 are normally referred to as street rotors.
T3 supposedly are for aggressive braking. track days etc.
Bfit

MY081 · November 27, 2018, 05:57:57 PM

The Brake guy who advertises in our mag is very good with price and very very helpful .Ray

gtc · November 27, 2018, 06:53:11 PM

Quote from: MY081 on November 27, 2018, 05:57:57 PM
The Brake guy who advertises in our mag is very good with price and very very helpful .Ray

https://www.racebrakessydney.com.au/

Ask for Matthew (and mention the Club).

Vettech · November 27, 2018, 09:09:21 PM

Yes I know Race Brakes, just over at Wetherill Pk, close to where I used to work.

Was going to take the 90 over and have the gear removed, cleaned, freed up on the pins, pads & discs checked.

I wonder if they do wheel alignment.

I can now as of twenty minutes ago drive the 90, tomorrow - first down to RTA, transfer + new plates, then maybe around the block to Race.

Might ask a few questions, let you know tomorrow.

Vettech · November 29, 2018, 03:50:57 PM

Nah - too much rain, decided to finish my new car.......

Vettech · November 29, 2018, 03:52:39 PM

My coffee table is now getting crowded..

I honestly did not expect that pic to load up - OMG.

Lefty · November 29, 2018, 05:46:45 PM

What car are you making?

bfit · November 29, 2018, 06:56:50 PM

Quote from: Vettech on November 29, 2018, 03:50:57 PM
Nah - too much rain, decided to finish my new car.......
[/quote
Quote from: Vettech on November 29, 2018, 03:50:57 PM
Nah - too much rain, decided to finish my new car.......
[/quote

Vette you seriously need a hobby
Bfit

MY081 · November 29, 2018, 08:27:56 PM

That looks like an Aston Martin (and that Dizy won't fit )

Vettech · November 30, 2018, 07:00:13 PM

Yes Ray Lego Aston Martin. Box says "Expert" - made for me.

Easy peasy, but you need bright light, good STRONG glasses, and patience to find the intsy pintsy bits.

The Dissy is out of my 78. This dissy would get me to the bus stop on Cowpasture Rd at Prairy Vale Rd, swapout with old style and continue to work.
That nite it tests OK, next day repeat it all over again.

Changed, Cap, Centre Contact, Leads, Dissy wiring, Senser, electronic module, every bloody thing, always tests OK, then fails at Abbotsbury.

I keep it here to remind me that I cant fix every bL$/% thing, also to remind me to get off my rear and make a machine to drive and check the little sucker.
Regards.