M caliper, Banjo fittings Options

[DanT]

will they work on a 914-4 front caliper in place of the normal brake hard line fitting?

[eeyore]

It appears that M caliper bolt and banjo fit on a -4 front caliper. It fit up snugly, with no wiggles, nor did the bolt bottom out inside the bolt hole.

I don't know if the mounting face of the caliper where the banjo goes is flat enough to properly seal.

[Eric_Shea]

Out with it... what the hell are you trying to do? (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif)

[DanT]

I thought you would figure it out Eric.

I am doing the cardinal no...no. I put my 914-4 fronts on the rear.
I know, I know....piston sizes and all that. (IMG:http://www.914world.com/bbs2/html/emoticons/ohmy.gif)

I just did not like the adjusting and all with the 914-4 rears. PITB. My hang up. I like just compressing the pistons and sliding in some new pads....clean simple, quick. Espeically at the track. got spoiled with my 944 turbo and Boxster at the track.

I am running M calipers up front with vented rotors and Porterfield R-4Es and basically stock PBRs on the rear with a "T". I am going to give it a try and see how it works. I had a 914-6 with JFZ 4 piston calipers at all 4 corners that worked very well.
The Ms and the stockers will give me some front bias....we will see.
I still have the stock rears so if it doesn't work out I will go back to the stock rears with competition pads.

Nothing ventured nothing gained....sometimes you just have to try it yourself.
And maybe screw up or maybe not.

I was going to use a banjo fitting to hook up the front calipers to the rear hard lines...but just "readjusted the existing hard lines to work without the banjos. (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)

[race914]

Hey Dan,

I think Larry Sharp did the same thing with his 'Sunoco' 914-6

If I remember right, it worked good for him

[DanT]

Well then I guess I am on to absolutely nothing that hasn't been done before (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

Talked to Gabe a couple of weeks ago....said he and his partner sold the 914-6. I guess they are both into motorcycles now!

Like I said if the balance is off I can either go back to the stocker rears, or I can install an adjustable bias valve. (IMG:http://www.914world.com/bbs2/html/emoticons/dry.gif)

Got my oil lines today. Will run them sometime this week and then it is ready to go to Sportech for the alignment and a few other goodies. Should be ready for BW with time to spare.

[fiid]

Do you have a prop valve?

I'd spend some time in an empty parking lot if I were you making sure they lock up in the right order.... be safe man.

[Aaron Cox]

QUOTE (fiid @ Mar 27 2006, 03:49 PM)

Do you have a prop valve? I'd spend some time in an empty parking lot if I were you making sure they lock up in the right order.... be safe man.

(IMG:http://www.914world.com/bbs2/html/emoticons/agree.gif)

[Eric_Shea]

QUOTE

Like I said if the balance is off I can either go back to the stocker rears, or I can install an adjustable bias valve.

After a short phone discussion with one of the weirdos that hangs out on this board, (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) I think I found a way to do away with the rear adjusters... (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)

Also... you're putting a piston on there that Porsche didn't use until 1984 (but you know... piston size) (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif) I would keep the P-Valve or FOR SURE... get an adjustable one. CIP1 has one for $45 clams that could be mounted in the cockpit.

[race914]

QUOTE

Talked to Gabe a couple of weeks ago....said he and his partner sold the 914-6. I guess they are both into motorcycles now!

I know where it went! It will be at Buttonwillow with its new owner for the PCA DE so you can check out the brake setup if still needed by then...

[DanT]

QUOTE (Eric_Shea @ Mar 27 2006, 03:20 PM)

QUOTE Like I said if the balance is off I can either go back to the stocker rears, or I can install an adjustable bias valve. After a short phone discussion with one of the weirdos that hangs out on this board, (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) I think I found a way to do away with the rear adjusters... (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif) Also... you're putting a piston on there that Porsche didn't use until 1984 (but you know... piston size) (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif) I would keep the P-Valve or FOR SURE... get an adjustable one. CIP1 has one for $45 clams that could be mounted in the cockpit.

I'm listening (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

[DanT]

I will be very cautious and slowly build up speed, until I am familiar and comfortable with the new set up. If I need an adjustable prop valve then I will try one. Still have the stock prop valve....sitting on the floor after removal from car.

I just took it out....a few weeks ago, before I decided to try this. (IMG:http://www.914world.com/bbs2/html/emoticons/ohmy.gif)

[Eric_Shea]

Let me know if you want to explore the rears without the adjusters. I think we can make it work. You'd be the Guinea Pig but from the tone of that last post (the one you deleted) ... you can handle it. (IMG:http://www.914world.com/bbs2/html/emoticons/lol3.gif)

[DanT]

Thanks Eric...what would we need to do.

yah, I decided that post was a little over the top for me....

I take things very carefully when I make changes to my cars....and don't plan on going out and doing a bonzai run on my local expressway (IMG:http://www.914world.com/bbs2/html/emoticons/unsure.gif)
You don't get as far as I have gone with track and AX driving without developing a healthy dose of reality and care.

The deletion of the adjusters sounds very interesting....let me know how we would proceed.

[DanT]

Eric,
now that we are on the subject what are the piston sizes for the front and rear of a '84 Carrera vs. M front caliper and 914-4 front caliper.

I want to run the ratios.

[Eric_Shea]

M Front = 48mm
M Rear = 38mm
914 Front = 43mm
914 Rear = 33mm
914-6 Rear = 38mm
Later M Rear = 42mm (this was the first 911 with a P-Valve BTW... (IMG:http://www.914world.com/bbs2/html/emoticons/idea.gif))

Remove the adjuster mechanism from inside the piston. Leave the adjusters of course (because they have the seals), but, in theory, those should work like regular brakes.

[DanT]

Thanks Eric.
I had looked at some old posts and found the sizes. 48v42 and 42v33.
.875 and .79 respectively on percentage of piston sizes.
48v33 is .69

I am going to try to off set the ratio by using a very mild street pad on the rear to go with the Porterfields up front on the Ms.
Will try this for one day in mid April at BW. If I have issues with this then I will reinstall the stock pvalve. If I don't do that I may just put in an adjustable pvalve and be done with it. I like the 914 fronts on the rear....I guess I am just a glutton for punishment (IMG:http://www.914world.com/bbs2/html/emoticons/wacko.gif)

I will report here my observations after my first track day, then you all may be able to say you told me so (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)
If I dont like that I may try to find a set of rear M calipers and go with vented rear rotors...although I don't know if I can get 4 lug vented rears...may have to have some redrilled if possible. Have you seen this done Eric, for 4 bolt rears? (IMG:http://www.914world.com/bbs2/html/emoticons/huh.gif)

[DanT]

a couple pics of the offending items (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)

I hope I can get them to work properly for me. They bolt on so easily and will be much easier to change pads.

[DanT]

and here is the shot of the reason I started this thread. I thought about using a banjo fitting to make the top feed hard line stay top feed. After much thought and discussion with my personal 914 gurus, I decided to massage the existing hard line to become a side feed line. As you can see it works just fine, if you take your time and don't kink the line. (IMG:http://www.914world.com/bbs2/html/emoticons/dry.gif)

[Eric_Shea]

QUOTE

then you all may be able to say you told me so

I doubt it... sounds like you're on the right track with the pads.

Rear M's should work as well. I'll bet if you took the spacers out of a rear M they'd bolt right up... no need to redrill the vented rotors. That would be my choice given your current sit-chee-ation. (send me the spacers and bolts when and if you do...) (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)