Line lock or leave as is?

[Cope]

How do you plumb the lock with out cutting the front hard line?

 

[demon322]

I know I can light tires immediately without the line lock being active, so we may be onto something about getting on the gas quicker.
Sometimes I'll hold all the brakes just until the tires start spinning then let off the pedal and let the lock hold the fronts.
It seems to not try to push though the front brakes as much this way.

This seems like it could work for sure. I need to play around with it some.

 

[demon322]

I cant say what's excessive, that's not my call...

I can say line lock is great. Why melt your rear shoes or pads? It's one wire and one cut in the hard line. Two step is also awesome. It's two wires VS how ever many thousands of dollars you have in your engine to not have to worry about over revving and launch at what ever RPM you chose. What's a two step cost, 45 bucks? That's a no brainer for me...

This is why I was asking about this now. I plan to upgrade to a new aluminum MC so the lines will be loose and I figured it would be a great time for new plumbing and only have to bleed once. Seemed like a great time to go ahead and add line lock, especially if I can use it in the future (5 speed) also.

Not sure on the two step yet but might look at something like that down the road.

 

[AJ/FormS]

I get the idea of a two step but that would be one more thing to add for just those couple of track trips a year. I don’t run a rev limiter at all at the moment.

I agree though that it will take some practice to find and be consistent with a launch rpm that works best.

A rev limiter might save your engine, I highly recommend one.
The A833 and period shifters are not known for their stellar performance, , especially on the 2-3 shift. If you get your shift-timing off,(hand/foot co-ordination) it's all too easy to miss the window, and with your foot back on the gas, 7000PLUS rpm may come.....and may go. I have seen the needle coming back down, falling past 8000; so obviously it was higher than that at one time,lol.
This can be a double whammy heart attack for your engine.
Firstly, the stock oiling system is not set-up for that, and you may loose a rod bearing or two.,and
Secondly, your valve spring pressure may be insufficient, and the lifters can loose contact with the cam.....and pump up....... and will attempt to drive the valves into the piston-tops.
Now 7000 rpm is ~116 revolutions per second. A regular shift may cost you up to .2 second. When you botch it, it'll be awhile before the revs fall below 6000.Your foot will come off the gas pedal, the car will be slowing, and the synchro is doing it's best, but no matter how hard you try, you will be scrambling to figure it out. So let's say it takes just a half a second for things to come back into focus. 1/2 second is therefore 58 revolutions.
This is a lotta revolutions of uncontrolled valvegear action. Certainly enough to do some damage, depending on how the engine was built.
In comparison to that damage, a rev-limiter is cheap.

The rod bearing damage may not be evident on the first over-speed. You may not hear it until the next pass......... or until the drive home.

 

[AJ/FormS]

How do I launch at the strip?
Well I've been to the track three times in my life with 4 runs each time,(1971,2001. and 2004) and about 4 successful runs in total. I dragrace like I street drive; rev it up, dump it, and hang on. Lousy technique, and lousy 60fts, so don't do what I do,lol.

 

[TrailBeast]

How do you plumb the lock with out cutting the front hard line?

Sorry, I was referring to adding brake lights with the lock without cutting.

On that note though I did mine a bit different than some and it works perfect, and I didn't even have to bleed my brakes when it was installed.
I used two 3/16 steel compression unions (brake systems rated) with one end of each union coupling threaded directly into the line lock. (Teflon taped the threads)
Then cut the line and inserted the brakes side of the line into the bottom compression union open end.
I filled the lock with brake fluid and a syringe, uncapped the master cyl end of the line and inserted it in the top fitting.
Tighten them both up and done deal.

For the Line lock to activate the brake lights I used a single wire with a diode inline run from the power wire of the lock to the lights side of the brake light switch.
This way power flows to the brake lights when the lock is active but does not flow back and activate the lock when the brakes are pressed because of the inline diode.
Flawless for 5-6 years so far.

 

[Cope]

AJ nailed it with that.

All you missed is the mic drop.

 

[demon322]

A rev limiter might save your engine, I highly recommend one.
The A833 and period shifters are not known for their stellar performance, , especially on the 2-3 shift. If you get your shift-timing off,(hand/foot co-ordination) it's all too easy to miss the window, and with your foot back on the gas, 7000PLUS rpm may come.....and may go. I have seen the needle coming back down, falling past 8000; so obviously it was higher than that at one time,lol.
This can be a double whammy heart attack for your engine.
Firstly, the stock oiling system is not set-up for that, and you may loose a rod bearing or two.,and
Secondly, your valve spring pressure may be insufficient, and the lifters can loose contact with the cam.....and pump up....... and will attempt to drive the valves into the piston-tops.
Now 7000 rpm is ~116 revolutions per second. A regular shift may cost you up to .2 second. When you botch it, it'll be awhile before the revs fall below 6000.Your foot will come off the gas pedal, the car will be slowing, and the synchro is doing it's best, but no matter how hard you try, you will be scrambling to figure it out. So let's say it takes just a half a second for things to come back into focus. 1/2 second is therefore 58 revolutions.
This is a lotta revolutions of uncontrolled valvegear action. Certainly enough to do some damage, depending on how the engine was built.
In comparison to that damage, a rev-limiter is cheap.

The rod bearing damage may not be evident on the first over-speed. You may not hear it until the next pass......... or until the drive home.

You make very good points here. I'm not anti rev limiter. I definitely will look into that when I get ready for the 5 speed swap, possibly check out a two step at that time as well.
For now since I'll be running the 727 at least for one more year I think I'll go with just adding the line lock when I do my MC upgrade.

 

[demon322]

For the Line lock to activate the brake lights I used a single wire with a diode inline run from the power wire of the lock to the lights side of the brake light switch.
This way power flows to the brake lights when the lock is active but does not flow back and activate the lock when the brakes are pressed because of the inline diode.
Flawless for 5-6 years so far.

View attachment 1715210752

This is a very cool idea!

 

[TrailBeast]

This is a very cool idea!

So then we have a light that comes with the lock kits to show when the lock is active.
That is also connected to the lock power, so when the lock is active the red light comes on up on my gauge pod on the dash.
BUT it does not come on because of the inline diode when you press the brakes.
Now if the diode does happen to fail they can fail two ways (open or closed).
If it fails open my brake lights won't come on with the lock. (not too big a deal)
If it fails closed the lock will activate when I press the brakes, but my light on the pod will also light letting me know this.
In this case I would press the brakes to slow or stop and the lock light on the pod comes on telling me the diode failed and my brakes will only release when I lift the pedal completely and the brake lights go off.
This would be the worst case scenario if the diode happens to fail, but the red light on my pod will tell me the system is in this condition as soon as I touch the brake pedal.

The lock I have is a progressive style, meaning if I have the button pressed for the lock on my shifter I can add holding pressure at any time or even just give enough pressure to resist the rolling in increments (like if you still want the car to roll but not completely freely.)
Don't know any useful reason for using this function except maybe for doing donuts, which I don't do anyway.

Another nice side effect is that I can flash my LED brake lights via the button on my shifter without ever touching the brake pedal.
I sometimes use this to flash the brake lights a couple of times as traffic is slowing or stopped in front of me giving a bit of pre warning to cars behind me before I actually start slowing the car.

 

[demon322]

So then we have a light that comes with the lock kits to show when the lock is active.
That is also connected to the lock power, so when the lock is active the red light comes on up on my gauge pod on the dash.
BUT it does not come on because of the inline diode when you press the brakes.
Now if the diode does happen to fail they can fail two ways (open or closed).
If it fails open my brake lights won't come on with the lock. (not too big a deal)
If it fails closed the lock will activate when I press the brakes, but my light on the pod will also light letting me know this.
In this case I would press the brakes to slow or stop and the lock light on the pod comes on telling me the diode failed and my brakes will only release when I lift the pedal completely and the brake lights go off.
This would be the worst case scenario if the diode happens to fail, but the red light on my pod will tell me the system is in this condition as soon as I touch the brake pedal.

The lock I have is a progressive style, meaning if I have the button pressed for the lock on my shifter I can add holding pressure at any time or even just give enough pressure to resist the rolling in increments (like if you still want the car to roll but not completely freely.)
Don't know any useful reason for using this function except maybe for doing donuts, which I don't do anyway.

Another nice side effect is that I can flash my LED brake lights via the button on my shifter without ever touching the brake pedal.
I sometimes use this to flash the brake lights a couple of times as traffic is slowing or stopped in front of me giving a bit of pre warning to cars behind me before I actually start slowing the car.

Is this something that you sell? I will be in touch for sure when I’m ready for the install.

 

[TrailBeast]

Is this something that you sell? I will be in touch for sure when I’m ready for the install.

Yep, currently 10 bucks shipped.
This is includes the 12ga wire, diode, soldered and heat shrinked ready to connect to your lock and brake light wire.

 

[demon322]

Outrageous! Way too expensive

(Expect a pm before too long.)

 

[Cudafever]

340 727 2500 stall 26-10-15 slicks
With out line lock: foot smashed on brake, 2nt gear, foot to floor. 6000 rpm SHIFT! car bogs down and stops spinning. with or without me continually applying the brake.
With line lock: apply brake hard, set line lock, release foot off of brake, mash the pedal to the floor, 6000 rpm Shift, high gear will hold at round 5000 rpm until i let go of the button. still bauges and stops spinning. but i have way over cooked the slick by that time.
With my 408, will keep burning them past the starting line if i want.

At our track, if you don't have a line lock, with a stick shift, it's REAL TUFF to stay at the starting line. The track travels uphill 7 feet in the 1/8 mile. it just won't stay at the starting line!