PM3 Feel?

[Prospeeder]

How should a PM3 feel? should they feel just like vacuum brakes? or no? mine just feel, well, completely different from conventional vacuum brakes, and do first gens just have really shitty stopping power or what, i just got new brakes 1000 miles ago and they suck ass still

[GutlessSupreme]

The PM3 in my TGP felt at least 2x as strong as the non-ABS vacuum brakes in the Cutlass, and that was with bad condition rotors and pads in the TGP. They're not all as good though.. I took no1kicker's TSTE for a test drive and noticed they felt about as bad as my Cutlass's, thought he had the ABS fuse pulled because it was giving him problems so I guess that doesn't really apply...

[Prospeeder]

mine do feel solid. like with vacuum, theres some travel, then it catches, and then its solid and u press and it slows down, it seems with the PM3 u press, it just goes a bit, u can feel it catch, but its sorta firm, nothing close to vacuum brakes, but u have to give it alot of pressure to stop

[futuretgper]

yeah thats exactly how mine feel...and i get alittle feedback from the pedal too.....pushes back against your foot some. i really hate the brakes! even if you nail the brakes and the abs comes on its still slow to get to a stop! im gonna be lookin into a wilwood custom kit next summer i think...my dads friend is a dealer for wilwood and he aslo has made a few custom kits that he sells...he said he would help me get something running...he suggested to go with manual brakes (no power vacum assist) so it would be super easy to do...and although the pedal feel would still be "stiff" you would have a ton more stopping power....

[Prospeeder]

i notice too, if u start to push it slow, sometimes, not very often, it will just be slowing, then suddenly let off, even tho ur still pushing the brake, then go back, scares the shit outa me

[mfewtrail]

I get the pedal feedback too. It was pretty odd the first time I drove my TGP vs. my other cars. My TGP will stop HARD if you want it to, I don't have to apply the brakes very much at all to stop normally with good condition rotors/pads on the car. I like it a lot better than my 93 GP's brakes....they'll be upgraded soon enough though.

[RareGMFan]

Prospeeder - You probably need an accumulator, too. That certainly will help consistency in brake feel and power quite a bit. Even though the PM III is a very similar system to the Teves II found on the '86 & up 6000 STEs, the 6000s feel a lot better over all as far as stopping power, and responsiveness. Maybe this is related, and maybe it's not, but the accumulators going out on the Teves isn't that common. They have more of a problem with.....the entire system going out.

[Prospeeder]

well, 3-5 pedal presses the acuumulator runs, and no abs lights, nothing of that kinda thing strange

[m0sh_man]

i just converted my 91GTP to vaccum brakes from a 1990 lumina and the car feels 100% better to me, brakes are alittle spongy, but atleast i have properly functioning brakes now, i think my problem is the rod that connects the vaccum booster to the pedal is alittle short (had to make a custom length one)

 

if anyone is interested i have two PM3 master cylinder units, including all the wiring and computer for one of the units, im not sure that they are bad, i think i had a wiring issue with my car.

 

my GTP's brakes with the PM3 seemed like it had a 2-3 second delay in braking, you press the pedal, and the brake light would come on, then the car would start to put alot of feedback on the pedal and the car would stop

but it would be 1-3 seconds before the car seemed to have much of a response on the brakes.

 

now, instead of removing the metal plate from the firewall of the lumina, i cut the plate off, and used 2 washers behind each bolt boss then bolted the plate in and turned and locked the lumina booster in place where the old PM3 system was.

 

i also had to replace EVERY hard brake line on the car except the drivers side front line, used all the lines from the 2 door lumina.

 

this was a total bitch of a job, and if i had known it would be this difficult i would have sold the damn car.

 

but atleast i have a 91GTP with brakes and getrag 284.

 

matthew

[john99gtp]

The PM3 in my TGP scared the shit out of me the first time i drove it. it has a weird feeling to it, and i feel some feedback when the pump kicks on (or cycles or whatever)

 

 

totally different then my 92 lumina with non abs and my 99 gtp

[Prospeeder]

i dont see what GM was thinking with the PM3, instead of making a Vaccum system with an extra computer and silenoids, they have to make some rediculously complicated expensive strange peice of crap ABS system

[THe_DeTAiL3R]

The brakes on my 88 weren't that bad- I mean they sucked but I liked how they "felt". Same goes for my 95 except the stopping power is 100x better. I dunno why, but I like the way the brakes are on my car. With new cars when you tap the brakes it stops too hard. If I wanna stop hard with my 95 I can do it I just gotta push down harder. I never need to mash it down or anything cause I don't have the need to stop that hard.

[digitaloutsider]

i dont see what GM was thinking with the PM3, instead of making a Vaccum system with an extra computer and silenoids, they have to make some rediculously complicated expensive strange peice of crap ABS system

That's just how things evolve. Yes, PM3 might be expensive to fix, but after driving a 92+ ABS-equipped W-body, I can attest to the fact that for first-gen W-body braking, PM3 is as good as it gets. The pedal feedback sucks, and it's quite different driving it, but overall the system isn't too bad. It's already saved my ass once.