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How to adapt the VT Master Cylinder to early model Commodores

Started by RB30-POWER · 13 Apr 2008 · 339 replies

Preserved from CalaisTurbo (partial recovery). Original authors and dates are shown; archived members are not current Holdcom accounts. View original archive ↗

jbonezArchived member
Part number for hoppers ones. Part number is BQ40A. Just double check there the right ones havent recieved mine yet. Got all my booster/ master bolted up, had to use an Na bracket drilled out about 2cm closer the the bracket but fited up okay. Waiting for line adapters & will be all done. Cant wait to see what shes got now.
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NZ VL comArchived member
pinch a set of front brake lines fron a VN up car instead of the adapters as then all 4 flares are matching the VT gear, just 1 adapter for the rear
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-Kenny-Archived member
Quote: Originally Posted by stuff I got the VT master with the original Reservoir tank/ VS booster, the vs reservoir tank won't fit on a vt master, and the 3 brass adapters got it for $66. mod the adjustment screw job on a vs booster to stop sticking the master out. Installed/bleed on a VK from last weekend, went for a run, it does improves and better response on brake pedal. $66 is a bit dear! hoppers quoted me $8 each plus $5 postage. replacing the lines with a later model is a bit difficult when u have an engine to weave around and with them being steel they can be easily stressed. I think getting them re-flared would hav to be the best option
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jbonezArchived member
Yea I wasnt going to pay $66 for them unless I had to. But hoppers seems to be the go. I mean you mass produce a threaded adapter & want to charge $20 each piece its a bit rich. When pirtek etc would sell a similar style hydraulic fitting for bugger all.
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5spdvlArchived member
Quote: Originally Posted by NZ VL com pinch a set of front brake lines fron a VN up car instead of the adapters as then all 4 flares are matching the VT gear, just 1 adapter for the rear Can be done, but I think you'd have a hard time "pinching" them. Rear brake line can also be used, but it'd probably be all wrong for the chassis. Some original photos have not been recovered yet.
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jbonezArchived member
Yea I think if you were going to goto the effort to pull your brake lines out, you may as well just take them to a shop to get the flares changed. But with the sensitivity of removing old brake lines from chassis mounts. Stuff that when adapters can be had for under $40.
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madrx3boyArchived member
does anyone know what size the adaptors are to use the standard vl fittings on the vt master? cheers
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-Kenny-Archived member
i hav some info and pics on how to adapt the vt booster. I can email but cant upload pic atm cos internet is slow. mite upload another day. Pm or email [email removed]
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GregaArchived member
kenny - i sent you a PM - i can help with the posting of pics dude.
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-Kenny-Archived member
internets a bit faster today so i'll post these up. cut out some 12mm plate. drill 10mm holes 60 x 80. blow out a 2inch hole in the centre (http://imageshack.us) (http://g.imageshack.us/img206/dscf0336ub4.jpg/1/) cut down the studs leave about 10mm potruding (http://imageshack.us) (http://g.imageshack.us/img206/dscf0338um7.jpg/1/) weld the plate to wots left of the studs. u dont wanna penetrate to much heat just a moderate tack is good enough (http://imageshack.us) (http://g.imageshack.us/img241/dscf0340iu3.jpg/1/) drill a few extra holes in the vl bracket to allow for spot weld. tack it to the plate. dummy fit the booster before u fully weld it, make sure the brake fluid resovoir is gonna be perpendicular. I had a spare booster that i refered to to put the bracket in the correct location. the bracket is pretty much parrellel to the plate (http://imageshack.us) (http://g.imageshack.us/img359/dscf0342si8.jpg/1/) when you've got it right complete your spot welds (http://imageshack.us) (http://g.imageshack.us/img359/dscf0343bw8.jpg/1/) by using the plate theres no need to drill holes in the pushrod. I wouldn't use plate any thicker than 12mm as it would make it harder to fit. the pedal should sit at the correct height however if it is still too high you can put a couple of washers on the 2 studs going into the firewall if you have to. the booster is a tight fit but it WILL go in WITHOUT any panelbeating. Some original photos have not been recovered yet.
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GregaArchived member
kenny, thank you.
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jbonezArchived member
Wow I wish I had those pictures a few weeks ago when I put the vs booster in.
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madrx3boyArchived member
Quote: Originally Posted by NZ VL com upgrade complete highly reccommended and thats with rear drums so the vt master/vs booster upgrade is fine to use with drums? i've read that the standard 15/16 master puts more pressure on rear drums to hold the shoes against the drum) which means when using a vt master (which is made for 4-wheel discs) won't put as much pressure on drums, and to me that means the rears will have an even smaller effect when braking (not that they do an awful lot for the ol' VL anyway lol. just wandering coz i want to put the vt master and vs booster in soonish but i still gotta get my new disc brake rear end converted to lsd
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NZ VL comArchived member
well it still stops good but i have a disc rear lined up soon to go in, that if i finish building it
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rb_insideArchived member
So what happens if the welds break
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jbonezArchived member
Well the welds are just to hold the booster into place.. If you get it welded properly I wouldn't expect it to happen.
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-Kenny-Archived member
welds wont break if u know how to weld. one thing i have noticed is that the firewall flexes when you apply the brake. so im gonna drill new holes in the vl master cyl/strut tower bracket to help support it. i'll throw a pic up when its done
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Com_VCArchived member
What’s the deal with the VS Master Cylinder Reservoir, the hole doesn’t line up as a lot of others have mentioned in this thread but in the first post it says to use VS Reservoir?
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markovrArchived member
You have to be joking...never trust a single weld to keep it all secure....use jimbos page as a guide and you bend your old bracket and weld it to another flat fabricated bracket ...you could even use the 10mm bracket but this setup doesnt depend on one single weld for strength and uses the original studs and nuts for strength like it was designed.... any weld just keeps everything together so it bolts up......use this site http://users.bigpond.net.au/jimbo123/VN/ under mods as a guide. its for a vn but the setup is the same for previous models like a vl
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madrx3boyArchived member
Quote: Originally Posted by NZ VL com pinch a set of front brake lines fron a VN up car instead of the adapters as then all 4 flares are matching the VT gear, just 1 adapter for the rear I've just Bought the VT upgrade for my VL (VT discs, VT calipers, VL to VT braided hoses). If i get the VN up front brake lines, can I still use the braided hoses that I got? If not then I'll just get the VL ones re-flared
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