Duel Master Conversion

**jrclem** · #1 (**permalink**) 11-22-2005, 01:49 PM

My main winter project is to put in a "Titon" type hanging pedal assembly, replacing my beloved floor-pivot clutch~brake assembly. I'm running VW Transporter front brakes and stock 2 liter at the rear. The question is: What size brake master cylinders (F/R) should I install in order to best utilize an in-car bias adjuster? Starting with a setup that is close will give me the maximum adjustment range. This is a pure race set up, and wimpiness is not a factor, I'm perfectly comfortable with the existing 7/8" Girling master... w/o booster. Anybody solved this quiz already?
Rick Clemente
#33 GTV B/S

**italcarguy** · #2 (**permalink**) 11-22-2005, 01:50 PM

You are going to put "tit on" your car?

**jrclem** · #3 (**permalink**) 11-22-2005, 05:15 PM

Tilton... grow up!

**catsboy** · #4 (**permalink**) 11-22-2005, 05:22 PM

The smallest Tilton M/S I see is 5/8", which is what? 15.8, 15.9 mm? So if you're running a 24mm at 63% front bias in a stock situation...
What about the Circle track guys? They're real good at setup on those dual masters. The dirt track guys are especially tricky...

**catsboy** · #5 (**permalink**) 11-22-2005, 05:37 PM

Sorry, I should have said 22mm with 63% bias...

genericwood · #6 (**permalink**) 11-22-2005, 07:01 PM

Rick, I recently did the calculations for total piston area for lots of brake combinations. The stock ATE set up has 61.5% of the total piston area in the front. If I'm not mistaken, the Transporter calipers have slightly larger pistons. So, if anything, you may need a slightly SMALLER front master cylinder to maintain balance. I would recommend either 3/4" cylinders for both ends, or possibly a 3/4" front and 7/8" rear. That should get you close. Due to some mathematical errors, I found myself this year running a larger front cylinder when I needed a smaller one. The result was rear lockup even when the balance bar was all the way adjusted to the front!

Erik

**italcarguy** · #7 (**permalink**) 11-22-2005, 08:49 PM

Rick,
Ok...I gotta reply to your post seriously.

Check with VARA to see if a modification like this puts you in "modified" before you do it unless you aren't concerned with points for next year. I know it's for safety so they might not care, but check anyways.

**jrclem** · #8 (**permalink**) 11-22-2005, 10:16 PM

I'm under the impression that this safety modification is likely to be mandated soon... and should not effect classification. But I will check it out.

**jrclem** · #9 (**permalink**) 11-23-2005, 08:54 AM

Anthony: VARA rules state the following:

General Safety:
B.6 BRAKE SYSTEM
Updated dual master cylinders and braided steel flexible lines are recommended.

B Sedan Supplemental Rules:
F. Brake and clutch pedals and hydraulic cylinders are free.

**italcarguy** · #10 (**permalink**) 11-23-2005, 09:03 AM

Cool, didn't want to see you get thrown in modified. I wish they just won't let cars in that fall under that class.

In that case, take a look at the #71 GTV race car next time you're in the shop. It has the Tilton set up you're looking for.

Biscione · #11 (**permalink**) 11-23-2005, 11:44 PM

Rick,

Have you considered the in line dual circuit MC from a '69 1750?

geneo · #12 (**permalink**) 11-25-2005, 08:21 AM

Rick,

Check out the Tilton (or in Anthonys case"tits) system on Gifford's 112 car . At one point I had the whole system out to change out the master and change the stroke of the clutch. Give me a call.

geneo

**Wil Painter** · #13 (**permalink**) 11-25-2005, 08:29 AM

"Have you considered the in line dual circuit MC from a '69 1750?"

Rick, this is what I've done; not as sophisticated as the Tilton setup, but I'm a softie for as many "Alfa" parts as possible. And it saved my floor mounted pedals.

Wil Painter