I have just installed impala ss ft. and rear disk brakes on my 74 with 77-79 cadilac fleetwood prop.valve. the impala master cyl is a quick take up cylinder but my hood wont close with it installed :( do I need a quick take up cylinder or can I use a corvette or trans am cylinder? the bore size on the impala is 1 1/4 with short rod

What type of reservoir are you using? The angled ones will swap on easily and can give you the clearance you're looking for.

Joe

its the stock no angled one. I'm headed for uwrench it in the morning to see what I can find. thanks

no luck today, only angled ones were 78 or so malibu and the front was very small. I didn't think it would hold enough fluid for rear disks. do I need the quick takeup master or can I get a smaller bore master?

Yes, there are other ones out there. I'll have to look at my notes though.

You do realize that the res. are hooked up "backwards" compared to what us old car guys are used to, right?

Joe

The 4wl disc SS master just looks like a quick take up. It isn't really. If you look at it, it is 1.25" front to back, with no step bore like the QTUs have.

There is a 1.25" Corvette style iron master, taking a short pushrod. The front port is for the front brakes, and the rear port might have a residual valve in it that you would need to remove if it causes rear drag. It is for a pre 1980 G30 Van with JB7 brakes. Cardone 101534.
I cant say it will work, but there it is.

If you used a 1.125" master you would have to be sure that the calipers don't have 'low drag' seals, and even then, it might make for a lower pedal.....
But using a 1.25" requires a lot of boost.....

Sorry I'm no help....

Originally posted by 72SSAbody:

You do realize that the res. are hooked up "backwards" compared to what us old car guys are used to, right?

Joe yea I noticed that and had allready made new lines before I tried to close my hood :( chevry, the valve is inbetween resivour and cylinder body

Go to Napa and purchase a NEW master cylinder part #39018 and make sure you have a "TRUE" 4 wheel disc prop valve. I purchased my valve through MP brakes. I have 79 firebird style front calipers and LS1 camaro aluminum rear calipers. My brakes work awesome. Make sure you move your clevis up to the top hole on your brake pedal if it was a manual brake setup.

The QTU valve between cylinder and resivoir is useless without a step-bore. The last time I looked, that master was not a step bore.

disc/drum Impala, 1.125"x 1.594"
http://img156.exs.cx:81/img156/4541/222024ov.jpgstep bore

disc/disc Impala, 1.25"x1.25"
http://img86.exs.cx:81/img86/1320/221954ty.jpg not a step bore.
++++++++++++++++++++++++++++++++

The Napa #39018 /1.125" bore should work fine... w/o 'low drags' ...but I think it takes a long booster rod. It's a 67-76 'Vette master.
For the same thing in a short rod style, use 78-81 'Vette #39052