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Commodore Booster to LH/X Rear Discs

Started by _rorym_ , Apr 19 2009 05:04 PM

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108 replies to this topic

#1 _rorym_

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Posted 19 April 2009 - 05:04 PM

Remove your old booster and master cylinder. Don't take the lines off the master just yet..pull it aside out of the way.

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Items needed.
1 x VB - VR Dual brake booster. Booster arm needs to be shortened 50mm back to 140mm fron the body face to the centre of the arm pin hole.
1 x PBR P10050 master cylinder.
1 x brake line made for front passenger side with Torana end with double flare and long Ford end with ball tip.
1 x brake line for drivers side same set up as above.

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Now on the rear inlet pipe you need to cut off the tip...remove the large screw head and fit a Ford long type end and ball flare the end.

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I bought one of these to do the ball tip or you can truck the car to a brake specialist.

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Obviously the 2 front lines go to the front and the rear line goes up the back on the new master cylinder.
Don't forget to drill the new booster arm hole the same size as the Torana one as the Commodore pin is smaller.

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I am plumbing in a Wilwood Bias brake adjuster into the rear line as well but the principle is the same.

More pics as I finish off the job.
R

Edited by rorym, 19 April 2009 - 05:06 PM.

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#2 Evan

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Posted 19 April 2009 - 05:59 PM

Nice one Rory.
You always do good tech articals which are always helpful. I had my laptop out in the garage when doing my LOKKA install

What are there advantages of upgrading my smaller DD UC booster?
Also where do you get an "PBR P10050 master cylinder"?
Why did you have to run new lines? Can you just modify the current line tips to the ford end with ball tip and not have to run new lines?

Evan.

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#3 76lxhatch

That was easy!

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Posted 19 April 2009 - 07:04 PM

Cool, any chance of a performance review in comparison to the old booster and master once you've driven it in anger?

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#4 _rorym_

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Posted 19 April 2009 - 07:41 PM

Nice one Rory.
You always do good tech articals which are always helpful. I had my laptop out in the garage when doing my LOKKA install

What are there advantages of upgrading my smaller DD UC booster?
Also where do you get an "PBR P10050 master cylinder"?
Why did you have to run new lines? Can you just modify the current line tips to the ford end with ball tip and not have to run new lines?

Evan.

Datto will confirm but I thought the UC was a single booster not a Dual.
Yes you can cut and mod the lines if you like..I chose to do new ones as they were $25 for the lot so seemed cheap to me.
P10050 from Repco or any brake/parts place.

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#5 _rorym_

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Posted 19 April 2009 - 07:42 PM

Cool, any chance of a performance review in comparison to the old booster and master once you've driven it in anger?

I reckon if it stops shit loads better that will be the guide..Lol!
R

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#6 _Torrie_Man_

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Posted 22 April 2009 - 06:26 PM

are there any alternate master cylinders you can use? say for a 6 banger?

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#7 _rorym_

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Posted 25 April 2009 - 12:21 PM

Fit the Commodore booster witout the master...I had to take it off again.
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Next you need to cut the end of the rear line off and remove the big flared end and fit a small Torana one, same ason the front guard lines.
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Now remove the passenger side line and feed in the new line. When bending it just make wide bends with your fingers. Don't kink the line anywhere. Remove the old booster and prop valve as a complete unit. When you have the passenger side line basically in place fit it to the new master. Now bolt the master onto the booster.

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Now fit the other lines, I have plumbed in a brake bias adjusting valve but the principle is the same.
Bleed the system.
Drive.
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R

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#8 _rorym_

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Posted 25 April 2009 - 04:32 PM

Next you need to cut the end of the rear line off and remove the big flared end and fit a small Torana one, same ason the front guard lines.

Only do this if you are fitting a bias adjuster into the rear..otherwise you will do a Ford ball flare type end and long Ford screw flare to suit onto the rear line straight into the rear hole of the new master.
R

Edited by rorym, 25 April 2009 - 04:33 PM.

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#9 _rorym_

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Posted 25 April 2009 - 04:34 PM

Now if Datto would come over and bleed it...I hate doing that bit!
R

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#10 dattoman

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Posted 25 April 2009 - 04:37 PM

You pay the airfare and I'll bring my bleeding leg

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#11 _rorym_

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Posted 25 April 2009 - 04:40 PM

Dont tempt me..we have a big one here 30/31 May..on TV.
Also must thank Neil for the advice and info...thats Datto by the way...and Rocket..the Jane hatch man.
Hope this makes it easier for you guys in the future. It was piss easy actually.Don't be afraid to tackle it.
R

Edited by rorym, 25 April 2009 - 04:41 PM.

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#12 dattoman

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Posted 25 April 2009 - 05:33 PM

Can't make end May... will still be in yankeeland
Try again

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#13 _rorym_

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Posted 29 April 2009 - 04:22 PM

One last thing....on the later Dual booster the rod is not adjustable..and with the P10050 the rod end needs to be dead inline flush with the bolt up face of the booster so it doesnt pre load the master.
Also,I couldn't get fluid out of the rear hole of the new master until I reverse bled it with that bloody big syringe and a bit of tube I have. Just push some fluid back up the rear hole...the bubbles will appear in the master...bolt on the rear line and bleed.
I also had to shorten the rod back 3/16" to be flush with the face with a grinder...as Datto said...slowly, slowly.
All is spot on now with a SOLID pedal.
R

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#14 _CHOPPER_

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Posted 30 April 2009 - 08:15 AM

So what is the advantage? Torana dual diaphragm boosters are still available. Is the Commodore one a bit smaller in diameter giving more clearance?

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#15 antelopeslr5000

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Posted 30 April 2009 - 04:19 PM

Same diameter.

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#16 _rorym_

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Posted 01 May 2009 - 07:50 PM

Cool, any chance of a performance review in comparison to the old booster and master once you've driven it in anger?

Testing over the weekend...I will post then.
R

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#17 76lxhatch

That was easy!

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Posted 01 May 2009 - 09:02 PM

Looking forward to it

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#18 _rorym_

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Posted 09 May 2009 - 05:26 PM

OK...first impressions are more feel through the pedal, rock solid pedal as well..moves about 25mm to biting....pedal pressure feels higher...might be from the big cam....squats really well now and you can feel the rears biting...fronts lock before the rears ...didnt hit them that hard to do 4 wheel lock up....when it starts to lock you can come off a bit to roll the wheels again..great feel as I said.
R

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#19 _robrenjus_

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Posted 05 January 2010 - 06:02 AM

thanks a bunch for posting this!!i just did this conversion over the weekend and it was very easy ,and as i already had the booster and master cyl from the vp donor car it saved me some dollars cant wait to test it out!!

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#20 _76lxJAS_

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Posted 07 January 2010 - 07:41 PM

hay mate just a question or 2.
was the bolt spaceing the same in the commodore booster as torana???
did you just cut and weld the rod to shorten it??
y not just use the commodore master cylinder aswell insted of the ford1??
cheers jason

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#21 dattoman

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Posted 08 January 2010 - 03:41 AM

Spacing is the same but bolt sizes are smaller
Washers will fix that

Yes he just cut and redrilled the rod I think

Commodore master is 15/16" Ford is 1" so went with the bigger one
There is a 1" Commodore that could have been used in place but costs more

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#22 _rocket_

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Posted 08 January 2010 - 06:16 AM

Or a WB statesman 1 inch.I used a VK commodore 1 inch unit on mine. I just cut 50mm off the commodore booster and weld the Torana end back on. Falveys have retained the Torana booster, used all of gear that I set up , like Rorys, but removed everything out of the proportioning valve, so it is now only a block.They dont have any problems with rear wheel lock ups, it all works fine, and has been tested at Bathurst numerous times.

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#23 yel327

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Posted 08 January 2010 - 06:52 AM

I remember years ago we used to do a similar thing but using a rebuilt HT/HG disc brake booster, but it was rebuilt with whatever pedal rod you needed and we used to put the front bit of a late UC booster on it. Used to work really well with HZ style 4 wheel discs with a 1" Commodore master cylinder.

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#24 _robrenjus_

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Posted 09 January 2010 - 06:41 AM

i used a vp v8 booster and 1" master cyl , took 50mm of the pushrod, washers on mounting studs and took the fittings also off the commodore took only hours to do.

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#25 _brett_32i_

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Posted 09 January 2010 - 01:36 PM

i used a vp v8 booster and 1" master cyl , took 50mm of the pushrod, washers on mounting studs and took the fittings also off the commodore took only hours to do.

are the 6 and 8's different on the p?