Line Lock Woes

[RBruton]

Recently had a B & M Launch Control installed(line lock) and its not holding weren't a dern. I tried new shoes on the front but they didn't improve the situation. Basically it will not hold the car even if I overpower the rear brakes and get them to spinning. I contacted Summit and got the answer that because the front brakes are disc it will not hold which I said was a bunch of BS cause they are being used all over the place. I also asked if this item is not gonna work with front disc brakes don't you think the manufacturer ought say something, ya think? I'm just trying to do a burnout without heating up my back shoes. I'm looking for suggestions. I didn't want to start throwing money I don't have at it. I have no idea what to do other then make sure its bled properly and possibly change out the hoses and calipers. The brakes seem to work fine with no pulling to one side or the other even with hard stops. The car has a rebuilt powermaster unit on it with no apparant braking issues other then there does not appear to be sufficient pressure before applied when the line lock is set.

 

[stockv6]

I've got the B&M line lock installed on my GN down on the frame rail, works well. Maybe you got a bad one? can you here it click? Is the direction correct?

 

[XLR8]

Did you try re-bleeding the brakes? Does the solenoid work?

 

[RBruton]

I have checked the direction and its correct. I can hear it click as well. I first thought it might be where it was installed because it was installed just off the master cylinder but after talking to several folks who had theirs there as well without problem so I'm not sure now. The unit will hold idle with a hard stomp and then set the switch but that's it, even with wet tires it won't hold. I'm gonna have my installer do some more checks to determine it the unit is bad possibly.

Is yours mounted on the frame rail before or after the proportioning valve and do you still use the powermaster braking system?

 

[Fuelie600]

Will the brakes hold the car when just foot braking to build boost?( no line lock ) Brian

 

[RBruton]

Yes with slicks they will hold while building boost if I have got the slicks hot enough. I'm still working on trying to improve the launch and determining just how far I can go that. I'm running a TE44 where the threshold is right at 5 psi where it slams to 25 psi. I can't hold any boost on the big 295/50R15 radials I sometimes run but the slicks are a different story.

 

[RBruton]

I gonna try re-bleeding the brakes and as far as I know the solenoid is working. The installer is gonna check the solenoid and determine if there is any leakage back through it.

 

[Nick Micale]

Originally posted by RBruton
I have checked the direction and its correct. I can hear it click as well. I first thought it might be where it was installed because it was installed just off the master cylinder but after talking to several folks who had theirs there as well without problem so I'm not sure now.........

Others may have it mounted just off the master cyl. but this is not proper or legal for NHRA safety. It MUST be mounted after the prop valve.

 

[RBruton]

Thanks Nick, that probably answers the location question. Arkansas doesn't have any NHRA dragstrips that I'm aware of yet but I'll keep that in mind for relocation in the future.