PPM sent me my stealth brake bolt and revised metering rod yesterday.
As you all may or may not know the factory Proportioning Brake Valve in 9C1s and Impalas was designed for drum bakes in the rear. It was not changed or altered from the factory for rear discs.
The stealth bolt and metering rod from PPM corrects the two problems associated with this factory setup. The stealth bolt itself changes the brake pressure from est. 95% front/5% rear to 65% front/35% rear. The metering rod alters the time delay, as the drum brakes need more time to activate, the front discs are delayed. This corrects that by having both fron and rear systems work at the same time.
A great many people say you just install, and forget it. WRONG! You have to bleed the system after the install to not only get the full potential of this mod, but also to get the air out. Infact, as sooon as my wife gets home, I am going to spend some quality time I promised her yesterday... You know. Hey Honey, pump, pump, pump, hold. Now repeat.
Bill Crovo's write up on the matter.
http://www.impalassforum.com/vBulletin/showthread.php?t=151985&highlight=stealth+bolt+brake+mod
PPMs link. http://powerperformancemotorsports.com/product.sc?categoryId=19&productId=1762
Remove factory bolt using a 3/4 wrench and a backer on the combi valve.
Remove plunger and spring from behind old bolt
Install new bolt and you are half way done.
Should look like this when done.
The metering rod is located at the back, and is tricky to get out. Just make sure wrench is on correctly or you could strip the bolt, making it harder to remove
You can see the difference in how they are shaped.
Two parts replace four