Converting to Disc using a Combination valve. Flare nut size illustration.
cdnpont said
Feb 4, 2009
CP'ers For reference, perhaps someone can use this someday.
For anyone who has converted their 65-70 B Body from front Drum to Disc, or even to Disc Disc, you know that unless buying a complete system or kit, finding the correct tube nut sizes takes a little research. Even on the same line size, apparently GM chose to have different front and rear system fittings to eliminate incorrect hook up on the assembly line.
To the best of my research, I've put together these 2 simple diagrams describing the tube nut sizes with standard colours you'll need if you plan on piecing together a system using the 71' and up style combination valve. The use of this style valve and master in "package" kits seems to be the standard today. It however can be daunting to find the valve that best suits your cars weight and balance, since hundreds of different combinations were probably manufactured. Anyone know the secret?
My combination is a 77-82 Corvette master. Delco #18M91. The combination valve is a CPP unit bought through Inline tube (PN PR-101). Described by them to be the correct choice for a Disc/Disc conversion on a larger car. Provides a 50/50 pressure balance...we'll see.
The master pictured is a Corvette style Delco Moraine unit typically used in conversions or kits. Used for illustration purposes only.
Napa part #'s; 1/2-20 x 1/4" line = 641-3324 9/16-18 x 1/4" line = 641-3323 7/16-24 x 1/4" line = 641-3298
The colours may vary. Follow the sizes carefully.
Cheers, Mark
-- Edited by cdnpont at 11:19, 2009-02-05
2drpost said
Feb 4, 2009
great info again mark. thanks.
427carl said
Feb 4, 2009
love the pictures
gparis7 said
Feb 4, 2009
Once again you are making it easy for the rest of us. Thanks for sharing the information.
Canadian Poncho said
Feb 4, 2009
Great stuff. Thanks Mark!
Icon said
Jun 4, 2009
wow this is great stuff, Glad to see its still around cause this is a must do.
eeluddy said
Jun 4, 2009
That definitly looks like the basic '70's Corvette master. They are cheap and plentiful everywhere. Thanks for the illustration. This is one for the archives.
-- Edited by eeluddy on Thursday 4th of June 2009 07:39:17 PM
davelacourse said
Jun 5, 2009
Now I know why I had to use every line wrench in my toolbox when I hooked my MC & prop.valve up - I thought it was just that the lines were put together by one of the Trailer Park Boys
Dave
427carl said
Jun 5, 2009
Trailer Park boys? turn off the tv
tin indian said
Nov 20, 2010
will that master still work with a big block, with tall valve covers, in a 66 parisienne? is there enough clearence? i,m asking because i havent installed the big bolock into my small block car yet. thnx in advance, colin
davelacourse said
Nov 20, 2010
Colin, why the tall valve covers? Are you running roller rockers?
Dave
tin indian said
Nov 20, 2010
yup, all fully rollerized, roughly a 530hp build. my avatar is the new 427 for the car, thats why i,m a little leary on space.
davelacourse said
Nov 20, 2010
I am no expert on B-bodies of your vintage but I am sure at least one other guy hereabouts is, and will give you the scoop.
Dave
CP'ers
For reference,
perhaps someone can use this someday.
For anyone who has converted their 65-70 B Body from front Drum to Disc, or even to Disc Disc, you know that unless buying a complete system or kit, finding the correct tube nut sizes takes a little research. Even on the same line size, apparently GM chose to have different front and rear system fittings to eliminate incorrect hook up on the assembly line.
To the best of my research, I've put together these 2 simple diagrams describing the tube nut sizes with standard colours you'll need if you plan on piecing together a system using the 71' and up style combination valve. The use of this style valve and master in "package" kits seems to be the standard today. It however can be daunting to find the valve that best suits your cars weight and balance, since hundreds of different combinations were probably manufactured. Anyone know the secret?
My combination is a 77-82 Corvette master. Delco #18M91. The combination valve is a CPP unit bought through Inline tube (PN PR-101). Described by them to be the correct choice for a Disc/Disc conversion on a larger car. Provides a 50/50 pressure balance...we'll see.
The master pictured is a Corvette style Delco Moraine unit typically used in conversions or kits. Used for illustration purposes only.
Napa part #'s;
1/2-20 x 1/4" line = 641-3324
9/16-18 x 1/4" line = 641-3323
7/16-24 x 1/4" line = 641-3298
The colours may vary. Follow the sizes carefully.
Cheers, Mark
-- Edited by cdnpont at 11:19, 2009-02-05
Once again you are making it easy for the rest of us. Thanks for sharing the information.
-- Edited by eeluddy on Thursday 4th of June 2009 07:39:17 PM
Dave
Trailer Park boys? turn off the tv