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Brake Booster upgrade - GTR to XU1


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#1 lxsstorana

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Posted 08 February 2007 - 03:14 PM

I have done a few kilometres in my GTR now and thoroughly enjoyed it. The only problem which has recently occurred was a stiffening brake pedal (you needed to apply more pressure to the pedal to make the car stop).

As I have new pads, discs, shoes and wheel cylinders I believed it had to be the brake booster (which it was). Decided to upgrade the standard single diaphragm booster to the XU1 double diaphragm booster and I can't believe the difference it has make to the braking system. Would thoroughly recommend it if your LC or LJ has disc brakes.

Very simple procedure. You only have to remove the split pin and pin from behind the booster, remove the vacuum hose, undo the 2 nuts securing the master cylinder to the brake booster (and push the master cylinder to the side), undo the 4 nuts holding the rear of the brake booster to the bracket. Remove the old booster and refit the new larger booster and refit the nuts and vacuum hose, pin and split pin.

The only other job to do was to re-shape the support bar from the booster to the inner guard, which is quite easy. Didn't need to disconnect the master cylinder or bleed the brakes. Less than 1 hour to remove and refit boosters.

I was quite lucky, as I picked up an XU1 brake booster for the right price (free) and just got it reconditioned. Cost $200.00 for reconditioning and 12 months guarantee (in Sydney). Can recommend a business in Sydney, they do about 300 to 400 large brake boosters each year and I watched him recondition a HK monaro booster whilst I was there. Anyways here's some photo's.

Mick.

Before (original GTR brake booster)
Posted Image

New larger XU1 brake booster
Posted Image

After
Posted Image

Edited by dattoman, 08 February 2007 - 04:06 PM.


#2 _LoneOranger_

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Posted 11 February 2007 - 09:37 PM

Did the same job to my car on Friday.
Not much pedal effort to gat it to stop now, Although there was nothing wrong with my old booster.
John.

#3 LOWS2

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Posted 21 February 2007 - 06:01 PM

Thanks for postng this up Mick, Ive actually picked up an XU1 booster to throw on my LJ and this will certainly come in handy. Just wondering if you could shoot me the name of the place that did your booster - ive been quoted $264 by a bloke near me & would be keen on paying a little less.

Cheers,
Mick

#4 lxsstorana

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Posted 25 February 2007 - 03:24 PM

Hi Mick,

I got my booster reconditioned at

"Automotive Brake Reconditioning"
Address 46 Adderley Street East, Silverwater. (Sydney) NSW 2141
Phone. 9748-4944 (Peter and his brother own the business)

Cost me $198.00 ($180 + gst) to get the booster reconditioned. Comes with 12 months warranty, new diaphrams, nuts + washers and painted.

Regards,

Mick.

#5 _gtr161s_

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Posted 01 March 2007 - 05:26 PM

just to add alittle more to the conversion of boosters.

I worked for better brakes in the early nineties doing upgrades from std to xu1 boosters was still fairly common.

Since there aren't so many xu1 boosters to be found it is a straight forward job to convert a std lc/lj booster to xu1 specs by using the large shell body off a hg.

The 2 shells are split, the internals sorted out to the same as xu1 rekitted, re-assembled and you have an xu1 booster for alot less than buying a second hand one which probably needs kitting.

Quoted $180-220 for the conversion late tast year (supply hg and std lc/lj booster)

#6 gooley

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Posted 28 June 2007 - 08:07 PM

The images dont pop up for me so could someone just send it to me

#7 _@milco@_

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Posted 26 September 2007 - 10:40 AM

yeah images not working anymore.....

#8 _Machine_

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Posted 15 December 2008 - 05:44 PM

hey here in perth they want $200 ish but thats for an exchange booster; already paid $150 for my xu-1 booster, starts to add up!

#9 red6

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Posted 16 December 2008 - 03:15 PM

i paid $100 of ebay, looked pretty rough but cleaned it up and it works fine

#10 glenn stanley

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Posted 19 March 2009 - 07:15 PM

Was the big booster an option on S SL and GTR from the factory or were all these models fitted with the single diaphram one?

#11 Dr Terry

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Posted 20 March 2009 - 12:28 PM

Was the big booster an option on S SL and GTR from the factory or were all these models fitted with the single diaphram one?

No, the larger booster was XU-1 only.

The smaller booster was standard on the GTR, because it had factory-fitted front disc brakes as standard. S & SL models only had un-boosted 4-wheel drum brakes, with the front disc brakes as an option, so the S & SL only had small booster if they discs at the front.

Dr Terry.

#12 _Genuine S_

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Posted 03 April 2010 - 11:22 AM

After the mention of the big booster , I thought I'd refresh the thread .

#13 _daf67_

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Posted 16 April 2010 - 09:40 PM

Was the big booster an option on S SL and GTR from the factory or were all these models fitted with the single diaphram one?

No, the larger booster was XU-1 only.

The smaller booster was standard on the GTR, because it had factory-fitted front disc brakes as standard. S & SL models only had un-boosted 4-wheel drum brakes, with the front disc brakes as an option, so the S & SL only had small booster if they discs at the front.

Dr Terry.


hi doc terry, could you please help me understand? im buy a xu1 brake booster.... question! is there a part number i should be looking for and if so where should it be.
question 2.... you say that the gtr brake booster was a standard single diafram unit as used on the standard s & sl mods, was there a special part number for the gtr from the standard mod. cheers dave

#14 dattoman

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Posted 16 April 2010 - 10:40 PM

GTR doesn't have a special part number
Its just a standard disc front booster

XU1 booster on an LC had a few numbers or equivelents
The one I refer it to is a VH316
But alot have a VH300 or VH305 tag on the front as many are modified HK/T/G units

http://www.gmh-toran...showtopic=15747

#15 S pack

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Posted 16 April 2010 - 11:01 PM

Was the big booster an option on S SL and GTR from the factory or were all these models fitted with the single diaphram one?

No, the larger booster was XU-1 only.

S & SL models only had un-boosted 4-wheel drum brakes, with the front disc brakes as an option, so the S & SL only had small booster if they discs at the front.

Dr Terry.


GMH did offer as an option a single diaphram booster for Drum front brakes on LC & LJ models.

#16 _daf67_

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Posted 20 April 2010 - 07:27 PM

Hi Mick,

I got my booster reconditioned at

"Automotive Brake Reconditioning"
Address 46 Adderley Street East, Silverwater. (Sydney) NSW 2141
Phone. 9748-4944 (Peter and his brother own the business)

Cost me $198.00 ($180 + gst) to get the booster reconditioned. Comes with 12 months warranty, new diaphrams, nuts + washers and painted.

Regards,

Mick.

hi , i looked at your add a few weeks ago and took your advise , i took my xu1 booster over to them , they rehauled it , top job , petes a ledgend. there good at what they do , thanks for posting that info ......... cheers dave

Edited by daf67, 20 April 2010 - 07:31 PM.


#17 _Mike73_

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Posted 25 September 2010 - 03:00 PM

Hi Guys,
There is one thing that everone seems to have missed, if you use a HT,G booster shell some had a different size Vaccum valve grommet hole, though not entirely sure why this was.

Mike

#18 _darkerheart_

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Posted 09 May 2013 - 06:55 PM

hey thanks guys,that was a great response for a first time member,now can anyone tell me where is the best place to buy a xu1 booster and is there a different push-rod length involved,regards ian



#19 dattoman

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Posted 09 May 2013 - 08:09 PM

There is one pushrod length to the rear of the booster where it bolts to the cantilever rod

95mm ... same as the standard booster

 

Theres 2 different lengths at the front to the master

25mm for LJ

8mm for LC

The master cylinders had different depths to the primary piston 

 

These figures are from memory and meausred from the front of the cannister

 

So since your car is an LJ... you want the deep one

Boosters can't be bought new anymore... so you'll have to hunt one up or modify a HK-T-G style one http://www.ebay.com....81f80c47&_uhb=1

Or try this guy and see if he has any to sell outright

http://www.hydroboost.com.au/index.htm



#20 _darkerheart_

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Posted 09 May 2013 - 08:21 PM

thanks neil,will do,should of joined this forum 5 years ago when i got the car,cheers.



#21 _eric73LJ_

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Posted 16 May 2014 - 06:29 PM

hey guys,

 

I've heard that you can put a vacuum can in to help braking aswell... Has anyone tried this and does it give much benefit? I'm told its supposed to be because you don't have a strong vacuum when you have a lumpy cam and this is helps it. does that run on a similar concept to having the double diaphragm booster from the xu1?

 

Regards, Eric






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