I'm with SVT Ky on this line loc.but not to lock the front tires for the start but for the burn out.If you are just power braking it you are super heating the rears AND how do you think they will help hold the truck back......if you just did a burn out with the brake on!!They WON'T.The rear brake HOLD the rear tires from spinning!!So now you did your burn out and OVERPOWERED them.And you expect them to hold.......stupid.IF they did hold it would be because you let them cool back down.DO a burnout with the lineloc them pull to the line and powerbrake the truck them!!Stan

 

RUSLOW,

Ever since I've had My lightning I've always hated one thing about it.

When going WOT then hitting the brakes, there seems to be a 1 second delay. They kinda work, then the power booster kicks in and halts the truck

It seems like the vacuum or pressure cuased by the supercharger making boost, doesn't deliver the vacuum to the brake booster.

Do you have a fix for this?

Example, Go to the 1/4 mile track, make a run at the end of the track hit the brakes, immediately after WOT, the brakes work (hard to push) then the power booster kicks in as the crankcase goes negative on my boost gauge.

I can't really explain it any better than go WOT, then hit the brakes immediately thereafter.

 

For the record, YES I WAS


This is why I always say mine is ABS related, even at 3MPH on a flat dry surface, the ABS will start freaking out when you hit the pedal

 

FOUND THE PROBLEM

The brake fluid was like jelly when it was changed today.From burnouts BEFORE I had the line lock, power braking and 140degree track temp on sat it all got me at once.
Hopefully this is all behind me now.

Thanks for the input guys and LeAnn.

 

Just a follow up on some parts you will need if you go with the Comp cams vacuum can. You will have to get a different power brake check valve. The one you need is in one of those red help packages number 80190. That part is an exact duplicate of our valve. You will also need to get some 11/32 vacuum hose to make your tie ins to the vac can...Hope this helps someone...

 

Glad to hear that's all it was.

What kind of fluid did you refill with?


FF

 

Oh *****, maybe I have the same problem then...

 

..me too, just installed a new brake booster...didn;t help...can you give me more specs on what to get and how & where to install?

 

Mine feels awesome without the ABS. I got on my brakes HARD a few times the 1st time I drove it, and the proportioning seems fine. From what I've read, a disc/disc vehicle doesn't necessarily need any kind of proportioning valve in it. If it does, I left an easy to get to spot where I can stick a $30 valve in to adjust the rear pressure. I really don't think I'll need one though.

 

I also have had brake issues since the new motor. My pedal slips down too far at times. I've bled the system three times now running 8+ounces through each caliper this last time. My fluid is all nice and new. It helps for a few hundred miles and then it returns. At this point, if I push the pedal hard it will catch and brake. If I feather the pedal, it will go slowly too the floor. It's definately worse now than ever. I've read that this is not an uncommon problem with F150s and in many cases it's the master cylinder. I'm going to replace it this time and see if that fixes it.

 

Here is a what I got.... Comp Cams PART #5200

 

if you are bleading the brakes by pumping the pedal,you may want to place a block under the pedal.this should br placed in a way to keep the pedal from going all the way to the floor.by doing this it keeps the master cylinder from over traveling its normal travel. this is the cause of the master cylinder going bad after bleading the brakes.when you stated you lost pedal when you feathered the pedal ,this is called bypasing .once this begans the master cylinder must be repared or replased.

 

Thanks for the FYI. I did not know that. That's exactly when my problem began and I did bleed the brakes by pumping the pedal. Next time, I'll add the block under the pedal.

 

Will replacing the mastercylinder really help this?..., don't want to spend all that $$$ and get no results.

 

if with the motor on and placing your foot on the brakes lightly,or feathering the pedal.if the pedal slowley goes to the floor,it is the master cyiinder.