I was looking on Mid-America's web site and a product called Performance Brake Bias Spring caught my attention. Anyone have any thoughts for experience with this product?
http://www.madvet.com/-/shop?frame=3.115.1125

 

I got mine from http://www.dougrippie.com/

I did a few other changes at the same time, lowered, poly bushings, revalved shocks, aggresive alignment, new ATE super blue brake fluid and Kumho MX tires. The car was great out at Watkins Glen and out on the street. I'm very happy with the changes i've made so far.

I've not heard anything bad about the brake bias spring and lots of good from fellow forum members.

 

I have the bias spring, too. It does interesting things for brake balance, kills some of the front dive. It's good!

 

Ditto!

 

Definitely a worthwhile addition..one of the few mods you can do that definitely enhance driveability for only a few bucks

 

I agree its great. Havent driven mine enough to tell since I just did the Z06 conversion but its in there. I put mine in a new master cylinder before putting it on the car. Helps if you have a sharpy permanent marker (the black cap and gray body) and a snap ring plier. I just put the spring in the piston, snap ring on top with the pliers engaged in the ring & compressed and with the gray end of the marker mashed it down while some one was holding the piston, went right in.

 

get the one from DRM. Listed above.

 

It's on my list.....

 

I got the one from DRM, great thing to do!!

 

Thanks very much for everyones input. I'll add this to my list.

 

Have one, works great.

 

Not to mention they are great people to deal with. They were late getting my spring to me, but it didn’t really matter since I was waiting on other parts as well.
When I received the invoice I noticed they had sent it 2nd UPS, and didn’t charge me any thing for shipping.
I thought that was rather nice of them.

 

Although I've seen this spring advertised quite a lot, I've never seen any technical information about it. Is it just a stiffer spring that allows a higher rear line pressure before it clamps/bleeds additional pressure, or what? And, why do I usually only see it advertised only for '85 and newer? Was this stiffness spring already used in '84? I'd appreciate any info on this.

Thanks,
Mike

 

Still waiting on hard facts I hear alot of "seat of the pants G pads" but nobody with facts.

I still maintain the the DRM spring "as shown with a C5" in their catalog works best with a C5. That car has near 50/50 weight, C4's don't.

If somebody wants to do a test, I'll give you the DRM spring out of my old master cylinder.

The test: Do 60mph and stand on your brakes untill the ABS kicks in, measure the distance within 1 foot. Put in the spring and repeat. Unless your maxing out your brakes at the point of ABS, you'll never know if you've gained that extra 12 feet.

LET THE FIREWORKS BEGIN

 

What is the spring force, when installed?

 

C4s dont have 50\50 weight dist. Its more like 51/49.

 

Yeah, what he said,...

 

That isn't necessarily true. By default the car puts a larger percentage of it's braking effort towards the front, which makes sense due to the weight transfer to the front of the car during braking. As such your front brakes almost always lock up first.

What can happen is that so much pressure is applied to the front brakes that they lock up, meanwhile the rear is not on the virge of locking yet. Most people will not continue to press harder after the pedal starts to pulsate, and so you are stuck in this pseudo locked state where the front is borderline but the rear can still use more pressure before they lock up, afterall they are smaller pads and calipers.

By increasing the brake bias towards the rear you are removing some of the weight transfer from the front and applying more braking pressure to the rear. This means that before the front ever locks up you will have applied much more pressure to the rear, making them do more work to slow you down.

So you're right, you probably won't notice any real decrease in braking distance unless you're in an all out panic stop, but in that event it will help dramatically. If the front wheels are still locking up, the rears will have significantly more force applied to them. The difference in braking balance also keeps the car more stable by not upsetting the weight balance as much if you were to brake late going into a turn, etc.

 

The spring was originally developed during the Corvette Challenge days. In a "spec" series with very little legal lattitude to modify anything, ANY minor advantage that the teams could find would yield major dividends on the track. So in a perfect world you could stay on the gas a few feet longer entering every corner on a roadcourse, it added up to either a bigger lead, or an opportunity to pass. This spring has been the subject of SOOO much misinformation over the years, largely due to a misunderstanding of what the REAL POTENTIAL gains are. In NO WAY does the spring change the bias to 50%-50%. I don't know what the exact factory bias is but for the sake of arguement let's just say about 75%-25% front/rear. I was told by a Corvette Challenge series winning crew chief that the spring only changes it approx. 5%. So in this example it would be 70%-30%. It is a meaningful change if you are expecting to push your brake system to the max on a regular basis, but other than that all you are going to accomplish is spilling brake fluid all over your engine compartment.

 

I've got a brake bias spring that I intend to install, the price was right. The problem with any part is that there is so much misinformation out there that it's hard to get any real info. I'm not expecting a night and day difference. It's time to flush my brake fluid again anyway, so why not?