Brake Proportioning

[mweeks]

After these cars are lowered is it necessary to install a manual proportioning valve to adjust brake bias?

 

If so, how do you remove/disable the factory one?, assuming its in the master cylinder.

[944-Spec#94]

brakes must stay stock, per rules. Rotors, Pads and rubber lines, fluid are the only non stock allowances. So we all use the stock brake bias.

[PeanutinCA]

don't you mean SS lines are allowed?

[Packfill]

OK, Weeks is scaring me......

[944-Spec#94]

don't you mean SS lines are allowed?

 

No,

I mean you can replace that stuff listed. Those include the rubber lines with braided lines. I don't think you can start replacing any of the hard metal tubing however.

 

Hope this makes sense.

[Tim Comeau]

Here's our rules regarding brakes. Installing a brake bias system would be trying to gain an advantage so no, it's not allowed. Our cars perform well under braking when we lighten them up to near the 2600 lb minimum.

             

Brake System

 

The brake system must remain stock including calipers, rotors and cylinders except as noted. ABS is NOT allowed on any model year, even if installed by the factory.

 

15.1 Brake Pads

Any brake pads are allowed.

 

15.2 Brake Lines

Steel braided brake lines are allowed.

 

15.3 Backing Plates

Disc brake backing plates may be removed.

 

15.4 Parking Brake

The parking brake lever and/or cables and associated parts may be removed.

 

15.5 Brake Fluid

Any brake fluid is allowed.

 

15.6 Brake Cooling

Brake cooling systems are allowed provided they use only air for cooling. Air may be vented through the fog light area in the front air dam for brake cooling.

 

15.7 Brake Rotors

Only stock sized brake rotors are permitted. Cross drilling or gas slotting of the rotors is allowed.

[mweeks]

Thanks guys, just checking.

 

Whats this "Weeks is scaring me stuff? Whats that about?

 

When you lower a car you change the C/G and when it is corner balanced to as close to perfect as you can get it, the brakes "MIGHT" need to be adjusted accordingly since each wheel is carrying an equal load, minus weight transfer during braking.

 

If Tim, who I can see by his results, is "the man" then if he says these car are just fine, then thats all I need to here.

[Packfill]

Michael...

 

No offense. You are just asking questions that I have never even thought of......It sounds like you REALLY know what you are doing. Good Job!!

 

I will be out at Willow this weekend, (maybe by myself....) if you can make it that way.

[mweeks]

Thanks for the support, actually I have no idea what I'm talking about, I am a mortgage broker

 

But it sounded good.

 

Anyway, I will not be at Willow this weekend because my 30mm torsion bars were back ordered, I got them yesterday , so I have not had a chance to put them in etc... But if I get bored on sunday, I might drive out to meet some guys. I live about an hour from Willow.

[Tim Comeau]

Michael,

You can always run with stock torsion bars. You could even enter the NASA HPDE group just to get track time. That's what the guys without licenses do.

[mweeks]

Tim you could'nt be more right, only I was expecting these a couple of weeks ago and dropped the rear suspension already. I have the front completed, 400lb springs etc. , I think the result would be a hairy oversteer , plus putting together once is my goal.

 

I "MIGHT" be able to borrow a car though. I just got off the phone with my step father, he just had a car built, and his car is supposed to be complete tomorrow! And he has a current medical issue that prevents him from putting on a helmet, so who knows, maybe I can make it.

[Tim Comeau]

That's great! Bill Addy will be there in the racing school and Jim Marks will be racing.

Edited February 10, 2005 by Guest

[Packfill]

OK, I am going stick my neck out and take the risk of sounding more ignorant then I am..... I am realizing that Kart set up is 180 degrees opposite of Cars, but

 

400 lb springs and stock rear torsion bar...

 

Isn't that Understeer?

[Tim Comeau]

Eric Sorensen ran this set up for a while and complained of understeer. Now he's at 30mm's in the rear too.

[mweeks]

Understeer........oversteer, either way not much fun.

[uberklasse]

I ran the same thing all last season! It seemed like a decent set-up actually for Willow. In my limited time behind the wheel this weekend my new 30mm set up (and over 3 inch lower car) handled great....the driving just sucked.

 

The stock with 400lb fronts is not terrible, just requires a lot of guts when flying through turn 9 at willow.

 

My hope is to actually have both set-ups since I plan on having my other car finished shortly

[Steven Rea]

Back to brakes...when running my spec car, it seemed like the rear brakes would lock up before the fronts, so on my next pad replacement, I was going to try running a slightly softer compound in the rear. I did this on my miata, and it worked great.

 

If you find either front or rears locking up first, this is an option that is legal within the class, in order to balance the front and rear brakes.

 

Good luck,

 

Steve

[944-Spec#94]

pad material is free. No where does it state that you must use any compound of pad in front or rear or that the compound must match.

 

 

I however run hawk blues front and rear. The rears seem to last forever.