Matt Lane

Had a chance to drive a nice 86 Carrera with the non-assisted brakes this summer. The brakes themselves may not be track ready, but pedal feel is FANTASTIC! ****-hard and confidence inspiring...

So, what's the consensus on a 993? Assuming good fluid and a regular bleed, is there anything to be gained in replacing the stock brake lines with steel? My car does DE and street double duty, FWIW.

How much improved brake feel / pedal firmness would you say is on the table with this change?

If you were to go ahead, who makes the best kits?

Looking forward to comments from those that have experienced a "before and after".

Best,

Matt

Mark in Baltimore

Steel lines don't make a bit of difference, in my experience. If your pedal is soft, the adjustment for the MC throw might be off. Try that first before you have your ABS pump rebuilt since the '95's (probably doesn't apply to your '97) had a bad batch of brake fluid that congealed over time. FYI, I had my ABS pump flushed and rebuilt and doing so didn't do a damn thing for pedal hardness.

Matt Lane

Thanks Mark - very sensible.

If anything, I'd expect my original lines to be swollen internally and hard, arguably with more pressure not less.

If you were to replace lines, would you just intall a new factory set? Would be interesting to hear how much degradation there is on brake lines approaching 15 year of use...

Best,

Matt

CHRIS WU

Replace with the steel lines,do the flush,drive it for a few days then do the flush again just to make sure all the air is out of system then go from there......

CHRIS WU

1997 c2s with 15000 miles when i bought her 2 yrs ago,GOOD pedal,but the brake lines were from 1997,the first thing I did is to replace the lines then did a flush,then flush again in a few days just to make sure all the air is out of the system,and now the brake pedal is nice and FIRM

Mark in Baltimore

Hey, Matt,

I'd be inclined to go with steel lines. I think Andreas did some heavy research on some good lines, so PM him for the brand.

race911

'86 with non-assisted brakes? How? A dual master setup?

As a comparison, when using the "Mercedes" master on the pre-assist ('76-and-earlier) cars converted to 930 brakes, or larger, the ability to modulate on the track sucks. Doubly sucks if you're not running the correct tire for track use. And triply sucks if you've got too much negative camber up front.

ABCar

I got nice steel lines from Darin at FD. Mine were old and crumby...I thought the lines made a nice, although not dramatic difference. It seems like these small upgrades/changes all add up to a an overall better driving experience. btw, they were only about $100 and the quality seemed very good.

Bill Verburg

Matt, brake feel is primarily a function of slave/master ratios and the stiffness of the components, way down the list is the flex from the brake lines, I'd replace 15yr old rubber lines as a matter of course, they do fail internally.

The only way to get a really nice pedal is to t/p in a C4 electro-hyd setup w/ 25.4mm m/c as used on the RS, this isn't cheap.

BradB

If the pedal is soft I have to think you have other issues. The 993 brakes (I have a 4S) are among the best anywhere. Mine have incredible feel. Very solid, no mush.

Use good fluid like ATE or Motul. Good brake lines are key, but the difference between steel and rubber is very negligable. (Most of the difference is psychological.)

Bill Verburg

By far the vast majority of racecar engineers will disagree w/ you on that. You are confusing effort w/ modulation.

ergonomically the human leg is far better able to modulate force at a fixed position vs over a moving range of positions, particularly so if you are operating the gas and brake w/ the same foot


w/ the 23.8mm m/c mention combioned w/ 930 brakes the effort goes way up but the pedal is rock hard and doesn't move a lot especially compared to a stock setup. This is mostly due to the slave/master ratios, the lower the harder the pedal
thru '76 911 41.3
boosted 911 thru '83 35.2
930 '78-89 33.1 early car w/ 930 brakes and 23.8mm m/c is the same just not boosted
964RS/Cup 32.8
993 37.3
993 tt 29.8
993RS 33.7
993 Gt2 evo 27.8
996Cup 30.1
997RSR 29.5

1pcarnut

Mine has steel lines and the brakes have a good firm feel. That being said I recall this question being asked to Joel Reiser on the PCA forum a couple years back and he said the factory rubber lines were very good and a better choice and even went so far as to not recommending the steel lines.

Stealth 993

I feel SS lines do firm up the pedal a little, but it may also be due to flushing the brakes at the same time.

Pedal softness has so many causes, like brake pad choice, brake fluid choice, overall brake system condition, & of course the brake pedal adjustment.

trophy

Pick a top quality fluid, Motul, Endless etc. This is cheap and easy, I went from Motul 650 to Endless and the improvement in pedal feel was amazing, and it was great before.

Mark in Baltimore

Did you feel a difference with SRF (as in better, worse or the same)?