Which hydraulic throwout brearing?
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Joined: Apr 2006
Posts: 53
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From: Conroe Texas
Which hydraulic throwout brearing?
Hi all,
I am swapping to a ls3/t56 magnum combination. I am using the 85 truck clutch master and wondering what throwout bearing others have used successfully? Did the smaller size (11/16" vs 3/4") cause any problems? Gathering my parts so I can get started.
I am swapping to a ls3/t56 magnum combination. I am using the 85 truck clutch master and wondering what throwout bearing others have used successfully? Did the smaller size (11/16" vs 3/4") cause any problems? Gathering my parts so I can get started.
Safety Car
Joined: Nov 2008
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From: Seattle Washington
I have never used OEM parts so I don't know what combinations work well togeather. I have used the Aftermarket ones though and can say that I would only use one that has two lines one for pressure and one for bleeding. I realise that there are millions of cars on the road today that use a one line Hyd Bearing but I have never figured out how one is to bleed one with out rolling the car over up side down. Another advantage is that it makes it very easy to do a Fluid change when there is a bleed line. As the Hyd Bearing is generaly the given size, one changes the Master size to control the amount of move ment. If You use the Search feture You can find quite a bit of info on this from me and many more.
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Joined: Apr 2006
Posts: 53
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From: Conroe Texas
Thanks for the reply, I have done a lot of searching but have not found exactly what I wanted to know. I was hoping someone has installed the 85 truck master cylinder on their car with a hydraulic tob, and got sufficient disengagement. 
Burning Brakes
Joined: Oct 2008
Posts: 1,037
Likes: 14
From: Mobile Alabama
Cant answer your exact question as I am using different trans. It will work if you match up the volume needed - smaller bore needs longer stroke, larger bore, shorter stroke. Matching your master to the volume of your slave and the distance needed for clutch disengagement. The clutch/slave manufacturer can give you numbers. You would not want to over work your slave and blow it out. I have over capacity, and just use an adjustable clutch stop.
Burning Brakes
Joined: Oct 2008
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From: Jersey Shore
I used the GMPP hydro throwout bearing with the Chevy truck master. Works fine. Although, I should mention that I have an LS T56 hooked up to a SBC with the quicktime bellhousing. I would assume its no different though.
The bearing comes with the factory quick disconnect fittings that need to be changed.
I used this:
http://www.speedwaymotors.com/LS1-an...ing,25017.html
and this (not necessary, but highly recommended):
http://www.speedwaymotors.com/T56-Re...der,41385.html
The bearing comes with the factory quick disconnect fittings that need to be changed.
I used this:
http://www.speedwaymotors.com/LS1-an...ing,25017.html
and this (not necessary, but highly recommended):
http://www.speedwaymotors.com/T56-Re...der,41385.html
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Joined: Apr 2006
Posts: 53
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From: Conroe Texas
Thanks vette427-sbc, I was hoping the gmpp bearing would work. Did you have a clutch stop or are you using the full stroke? Also, do you rember what fitting you used to adapt the master cylinder line? I beleive it is a bubble flare, but I have no idea how to determine what size.
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Burning Brakes
Joined: Oct 2008
Posts: 955
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From: Jersey Shore
Yeah I used a pedal stop to prevent the master from bottoming out. Pedal throw is about 2/3 of stock.
I *think* the master cylinder fitting is a 12mm bubble flare? Napa sells the conversion fitting to go from the 12mm bubble to 3/16" hardline. I just had a local hydraulic line shop make me a braided flex line so I could bleed everything out of the car, and leave it all connected while I put the motor/trans in.
Also, make sure that the bearing you get is for a magnum... they might use a different one from the regular LSx style.
I *think* the master cylinder fitting is a 12mm bubble flare? Napa sells the conversion fitting to go from the 12mm bubble to 3/16" hardline. I just had a local hydraulic line shop make me a braided flex line so I could bleed everything out of the car, and leave it all connected while I put the motor/trans in.
Also, make sure that the bearing you get is for a magnum... they might use a different one from the regular LSx style.
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From: Forked River NJ
I used the GMPP hydro throwout bearing with the Chevy truck master. Works fine. Although, I should mention that I have an LS T56 hooked up to a SBC with the quicktime bellhousing. I would assume its no different though.
The bearing comes with the factory quick disconnect fittings that need to be changed.
I used this:
http://www.speedwaymotors.com/LS1-an...ing,25017.html
and this (not necessary, but highly recommended):
http://www.speedwaymotors.com/T56-Re...der,41385.html
The bearing comes with the factory quick disconnect fittings that need to be changed.
I used this:
http://www.speedwaymotors.com/LS1-an...ing,25017.html
and this (not necessary, but highly recommended):
http://www.speedwaymotors.com/T56-Re...der,41385.html
Thread Starter
Advanced
Joined: Apr 2006
Posts: 53
Likes: 3
From: Conroe Texas
Working on finding out which bearing fits the magnum. Transmission vendor does not know what oem will fit, it would cut into their sales of the expensive part they recommend so no incentive to find out. Contacting Tremec tomorrow, hopefully get an answer. Thanks everybody for the information and reassurance that all of this can come together.
Burning Brakes
Joined: Oct 2008
Posts: 1,037
Likes: 14
From: Mobile Alabama