19mm Master Cylinder Options

[marks914]

OK
I have read many articles about the 19mm master cyl. upgrade. Just wanted some feedback. I know that the 19mm will have a pedal that is harder to push. I am installing a five lug conversion right now. Up front: 82 SC rotors and calipers (non turbo). In the rear: stock 914-4 rear calipers and rotors. Could I get away with a 17mm? I would like a easier pedal. Has anyone used the 17mm with a similar setup?
I am also getting cold lying on the floor of my garage. Here in Detroit its getting cold!
Thanks
Mark
Oh yeah, found out that my15x7 polished fuchs( 23.3mm offset) stick ouy as far as my rear fender lip. Guess I will use my phone dials.

[SpecialK]

I've got the BMW 320i calipers up front, 19mm MC, with stock rears and a "T" in place of the proportioning valve. Can't give an opinion on how well this set up works because everything is still boxed up and sitting on a shelf in the garage.

A PP article might be helpful in answering your question:

http://www.pelicanparts.com/techarticles/9...MW_calipers.htm

If not, at least you're bumped up the page (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/icon_bump.gif)

Kevin

[John]

I'll add my $0.02

We had a 19 mm master cylinder on our track car (1983 SC front calipers on front, 914 front calipers on the rear).

The pedal travel was ok. The pedal pressure was not overly firm. With a 17mm master cylinder, the pedal travel will be greater than a 19mm due to volume of fluid required to move the caliper pistons.

When our 19mm master cylinder wore out, we went to the 23mm master cylinder which worked out much better (even less pedal travel). You can really press hard on the pedal.

I feel that there is more control with the larger bore master cylinder as the pedal pressure that you are able to apply has a greater range than that of a smaller diameter master cylinder.

With the reduced pedal travel, it is easier to heel-toe (in my opinion).

Now with our current setup (930 front calipers up front and 914 front calipers in the rear), the 23mm master cylinder seems to feel almost ideal (pedal firmness and travel).

In short, if you are going to replace your master cylinder (with 911 calipers) I would not use a 17mm master cylinder, but go with either the 19mm or the 23mm.