My car was originally disc/drum with 15/16 master and single diaphragm booster. I now run twin piston VT calipers/rotors up front, vl turbo rear, 1 inch bore master and the original booster. Car brakes awesome and have never had a problem. The PBR part number for the 1 inch bore master is P10031, VL turbo, VL V8 and VN V8 all run this master as factory with a twin diaphragm booster, i am running a single diaphragm booster with no probs. These master cylinders have an aluminium body with a teflon coated bore, one scratch or pit in the teflon and they r ****ed, it will leak and cause problems, best off buying a brand new one. Dale.

Thanks Dale that was VERY helpful! Looks like thats the way I'll be going then. How much for a NEW 1" master?

Quote: Originally Posted by VLHERO Thanks Dale that was VERY helpful! Looks like thats the way I'll be going then. How much for a NEW 1" master? No probs mate, i worked for a brake and clutch mob for 4 years and its amazing the things your brain remembers. I got mine pretty cheap as i was still working there at the time, but i would expect u to pay around $200, but i could be wrong. If u have a mate in the automotive industry, he should be able to get u one at a decent price from one of his suppliers. I dont reccommend getting a second hand one as its really taking a gamble as u dont know how long it has been sitting there or the condition of the master itself inside. Alot of ppl now are selling the VT upgrade kit for the VL, its a great conversion and well worth doing. The VL brake setup runs a hub type disc, whereas the VT setup runs a floating disc, the kit will include a conversion hub for this reason.

i have done the upgrade to discs on the rear and did a full cert without needing to change the master, theres no difference between the disc and drum masters besides the 1" onwards, you wont really find a hell of a lot more difference apart from the looks, upgrade the fronts at the same time and when you hit the picks youll be hitting your head on the windscreen man Some original photos have not been recovered yet.

Quote: Originally Posted by Dale No probs mate, i worked for a brake and clutch mob for 4 years and its amazing the things your brain remembers. I got mine pretty cheap as i was still working there at the time, but i would expect u to pay around $200, but i could be wrong. If u have a mate in the automotive industry, he should be able to get u one at a decent price from one of his suppliers. I dont reccommend getting a second hand one as its really taking a gamble as u dont know how long it has been sitting there or the condition of the master itself inside. Alot of ppl now are selling the VT upgrade kit for the VL, its a great conversion and well worth doing. The VL brake setup runs a hub type disc, whereas the VT setup runs a floating disc, the kit will include a conversion hub for this reason. Yeah Im aware of the needs for the VT conversion. Was considering going R32 but even if I get the calipers cheap (say $250) Im still gonna need adaptors, lines, pads, rotors, etc etc. From what I can tell it would end up somewhere round the $700-$800 mark. VT conversions can be done for $600 from start to finish and they'll be perfectly capable of pulling the car up with the RB20 I plan on dropping in. How much did you VT setup cost you mate? Do your old mob give discounts to ex-workers? Some original photos have not been recovered yet.

Just commodore spares have a vt brake upgrage with slotted discs for $595.00 i am unsure if this is with adapters, but i plan on doin this soon so let us know how it goes. If you do this you almost have to put a 1" MC unless you wil have a uselesspedal until it is at least halfway depresed, which means ur brakes wont be working 100%

Quote: Originally Posted by 427vlc Just commodore spares have a vt brake upgrage with slotted discs for $595.00 i am unsure if this is with adapters, but i plan on doin this soon so let us know how it goes. Will do mate, have now found the full conversion for $480 so it will be on by mid June.

I think Steve just missunderstood your first post...... You are correct by saying there are: 15/16 disc/drum 15/16 disc/disc 1" disc/disc A VL or VS master cyl will do exactly the same job if its 1" I would personally buy a new 1" master cyl from a VLT/VN V8. I think VS's have slightly different outlets? Mine cost me about $170 a few years ago. If you go the VT brake conversion you will need this m/cyl as a minimum. For some people the pedal feel is good, for others its spongy- depends on brake lines, pads etc. The best conversion would be 290mm VLT discs (DBA017) with series 4/5 RX7 calipers. These will give a great pedal feel and clamping force. I will have the fitting kits available shortly for these.

Quote: Originally Posted by vhr32 I think Steve just missunderstood your first post...... You are correct by saying there are: 15/16 disc/drum 15/16 disc/disc 1" disc/disc A VL or VS master cyl will do exactly the same job if its 1" I would personally buy a new 1" master cyl from a VLT/VN V8. I think VS's have slightly different outlets? Mine cost me about $170 a few years ago. If you go the VT brake conversion you will need this m/cyl as a minimum. For some people the pedal feel is good, for others its spongy- depends on brake lines, pads etc. The best conversion would be 290mm VLT discs (DBA017) with series 4/5 RX7 calipers. These will give a great pedal feel and clamping force. I will have the fitting kits available shortly for these. Fitting kits being just the lines and adaptors I take it? Not a complete conversion?

The VT upgrade kit should come with everything u need to bolt straight up. The kit will come with a conversion hub(the most important thing), that will bolt on to your standard stub axle using vl wheel bearings, the VT disc will then sit over the top (a floating setup unlike the VL's standard hub type) and the VT twin piston calipers will bolt straight up to your standard calipers mounting place with the original bolts without having to use an adaptor plate like when fitting RX7 calipers/nissan four spots etc, the kit will also come with the flexible hoses to suit. The upgrade is an easy and cheap conversion and the braking performance is unbelievable, must be used with a 1 inch master. My pedal is hard as a rock even with the single diaphragm booster(standard 6 cylinder booster). 15 inch chasers will just fit over the top if ur after the sleeper look, but if u have alloys at least 17 inch minimum for clearance issues. Not only does the car brake better because of the fact the calipers have twin pistons and a larger pad, but the discs are actually 5mm thicker than standard or VLT discs, which help greatly in regards to heat and shudder problems. This setup should be more than adequate in pulling ur RB20 VL up and outbreaking many later model cars. I have this setup on both my VL Turbo's and fully recommend them with no dramas. Dale.

Quote: Originally Posted by VLHERO Fitting kits being just the lines and adaptors I take it? Not a complete conversion? Yes, just the laser cut steel brackets, bolts/nuts/washers and new banjo bolts. You use your origional brake lines. Should have the first one done this weekend, taking forever to get right!

i did a drum to disk conversion on my mates vl, we took it for a spin and he said it braked 10 times better then with the drums, you will be fine dude. tim

Quote: Originally Posted by PHATGM why wouldn't you buy one from a wreckers? You should not FIT a hydraulic component to your car from a wreckers.If you buy a master cylinder for example get it cleaned and rekited first.Do you know how many times people come into our shop that have fitted secondhand master cylinders from wreckers and have then had to change them because they where faulty or had some foreign fluid put in the reservoir.That is why you should not fit a master cylinder from a wreckers. Quote: Originally Posted by VLHERO What are you on about? N/A Calais got discs all round with the 15/16 master cylinder. Only turbo's and V8's got the 1". VT brakes are twin piston, and can be used with 330mm rotors. You've obviously got no idea what your on about mate!! You are right about the fitment of the master cylinders but you missed the point i was making.My point was the fact that a disc/drum master cylinder and a disc/disc master cylinder is different ,therefore you should change the master cylinder if going from drum to disc in the rear of a VL or any other car.You should take a deep breath. VT brakes are twin piston you are good but there was a problem fitting them on 330mm rotors as the pads hung over the disc because of the radius.If this has now been fixed and someone has made the bracket i would love to know.We found at my brake shop that i own another model cars twin piston caliper actually fit the 330mm rotor better and was more rigid than the VT caliper therefore having less flex.

i too am looking at doing the VT brake upgrade, but currently have the 15/16 m/c and drum rear. will be doing rear disk conversion too. when upgrading the master cylinder do you need to replace the brake booster as well? is it just best to buy a complete 1inch master and booster.

I have now a double diaphragm booster which is 40% better that has also been modified to take the VT master cylinder this will replace all single and double diaphragm boosters .I am working out a cost as not everyone will have a booster to exchange.

How much brake fluid is in the lines and m/cylinder resovior? I'm going to change the m/c but im not sure how much fluid i'm going to need after i bleed the brakes. I have a 500ml bottle is that enough? It's got 4 disc brakes.

It's more than 500, by the time you waste some fluid bleeding the brakes. 1 litre will cover it.

Thanks mate thought i better check first before i do it and realise i dont have enough Some original photos have not been recovered yet.

vt 330mm front floating disc and 315mm rear discs with vz rear calipers, braided lines all bolts, hubs and spacers included just need vlt master 1''. $1600 the lot very good quality i have them and did a track day at sandown braking from 200kmh at the end of front and rear straight for up to 15 hot laps in a row and no fade, warp or squell...