LS guys what are you doing for your power brakes?

[cheesepocket]

I never drove my car with the six for comparison, but if I hook the vacuum line from the booster to the factory tube on the LS1 manifold, I get way too much assist, like stepping on a marshmallow and then way too much braking for the effort.  Really tough especially to heel-and-toe that way.

 

I tried leaving the vacuum source capped, but then it's alarming in how much effort it takes, and I feel like I'm gonna put my foot through the thin firewall.

 

I tried getting an industrial valve designed to regulate pressure/vacuum, but all that did is allow full boost for maybe 1.5 pumps and then the booster was depleted.  In other words it regulated the volume but not the pressure.

 

I have the stock front disc and rear drum setup stock for my 72 240, and don't want to go down the road right now of the full front/rear and master cylinder upgrade, just want to drive the car for awhile.  I doubt I can just mount the master right to the firewall and simply delete the booster, but I don't mind manual brakes if it's easy and relatively cheap.

 

I didn't post this in the brakes section as I am hoping for an LS-specific solution that might still allow me to use the booster.

[alrighty]

Running a sentra booster with strange master cylinder(120$).I'll let you know here in the next few days how it brakes.LS1 with T56 and AZC (4 piston)brakes front and rear is what we are running.

[randy 77zt]

Any engine makes about 20" of vacuem under closing throttle-it doesnt matter what motor made the vacuem.If you increase the bore size of the master cylinder it will take more effort on the pedal.

[milesz]

I never drove my car with the six for comparison, but if I hook the vacuum line from the booster to the factory tube on the LS1 manifold, I get way too much assist, like stepping on a marshmallow and then way too much braking for the effort.  Really tough especially to heel-and-toe that way.

 

I tried leaving the vacuum source capped, but then it's alarming in how much effort it takes, and I feel like I'm gonna put my foot through the thin firewall.

 

I tried getting an industrial valve designed to regulate pressure/vacuum, but all that did is allow full boost for maybe 1.5 pumps and then the booster was depleted.  In other words it regulated the volume but not the pressure.

 

I have the stock front disc and rear drum setup stock for my 72 240, and don't want to go down the road right now of the full front/rear and master cylinder upgrade, just want to drive the car for awhile.  I doubt I can just mount the master right to the firewall and simply delete the booster, but I don't mind manual brakes if it's easy and relatively cheap.

 

I didn't post this in the brakes section as I am hoping for an LS-specific solution that might still allow me to use the booster.

I am having the same problem.  Please let me know how you fixed the problem.

[zdlite]

classic symptoms of a mis aligned reaction disc.  Do a search on that topic and read the write up on how to fix it.

 

I run a stock booster and ZX MC.  No issues with the 23" vac at idle.

[1 tuff z]

I'm running the later zx 15/16" booster and the pedal pressure/feel suits my needs fine. Able to heel/toe and effectively modulate the brakes both on the track & street and the larger booster masks my lack of race car driver smoothness and makes my heel-toe feel like I actually know what I'm doing, thus making [passenger] perception = reality!