Anyone run a line lock with an auto tranny?

I’ve got an extra hurst one sitting around and have been debating installing it but have been wondering if the advantages with an auto outweigh the pound or so extra weight and “more to think about” factor (neither side is a big deal, but I’m not sure that I can justify running a line lock with an auto since burnouts are a piece of cake without anyway. OTOH, they’re easy enough with a stick and I installed on on that car).

I wouldn't even be thinking about it if I didn't have one sitting around and didn't have the tendancy to make a lot of dragstrip passes at times...

 

Regardless or tranny. it's dumb not to install it if you make frequent passes, why glaze/burn up brake shoes/pads when you have a 30minute solution at your disposal??

Suppose you could do the old school trick of backing off the rear brake shoes, but that's just goofy since you cant stop as well.

You've got the know how and the parts, just get'r on

 

Line lock - don't leave the staging lanes without it.

Assuming you have slicks, that is...

 

I have the Nitto 555DRs on my car now, and I just went racing again today. First time this year, but the 3rd time with the tires. I think they are finnaly broke in. Anyways, i think I need the line lock. I have a cutback valve in my rear brake line, that cuts pressure to back brakes by like 50%. But I still cannot get a good burnout. Tried going thru the water, and got the tires wet, and that helped. But no smokey burnout like everyone else.

What is the best deal on the line locks? Like 100bucks at Summit?

 

I've been running 2 biondo units in my car for 4 years, thousands of passes on them and not a hiccup yet, think they're like $40 in Summit.

 

Me too with Biondo. You don't need some fancy billet aluminum, expensive line lock for it to work.

When I heat my tires up, I'm after wheel speed. If I'm spinning the slicks around 100 mph in the water box (high gear and around 5000 rpm), having the brakes dragging will cause them to heat up real fast. After crossing the finish line at close to 130 mph, I don't need brake fade.

 

That’s the reason that I finally bought one for my 6 speed car…, not that I couldn’t do a burnout without it, but that I got tired of seeing the rear rotors BLUED from the heat of the burnout in the staging lanes… that and it’s always weird when you find yourself replacing rear brakes much more often the the fronts (I’ve replaced the rears 4x now on that car and it still has the original front brakes).

9” is setup for LT1 rear disks… so it’s not really an option.

well, I’m debating seeing if I could rig it as a bypass for the prop valve on the rear brakes so that I could send full brake pressure to the rear brakes allowing me to hold more boost on the line…

 

Yea, I've found that short, second or 3rd gear burnouts work best depending on the tires.

 

So you Pro-racers are happy with the Biondo units?
I checked my Summit catalog, and they have like 5 different choices for roll control.

Hurst = $110
TCI = $82
B&M = $70
Summit brand = $90

and Biondo = $40

All of them come with switch/light/fuse, except the Biondo. But I think I can handle that part of itat Advance Auto.

Kind of looks like a no-brainer!

 

Mine were easy to install and have been trouble free since installation. They're not nearly as fancy looking as the other high dollar brand, but last I checked, fancy/shiney did'nt win any races

Wire, toggle switch, and momentary push button is all you need and will not cost you near as much as what the others want for theirs. Great unit, simple, cheap, and proven effective....kinda like my Proform electric water pump

 

theres a couple ways to install them too, most tend to installt hem in the front brake lines to hold the front brakes tight allowing you to let go of the brake pedal so the rears dont drag,

ANOTHER way is to install it backwards (it will allow fluid to flow in one direction and block the other direction when activated) in the rear brake line, which will block any fluid from going to the rear brakes, what this allows is you are now able to get on the front brakes harder should you start rolling out of the burnout box,

since with the first way you are stuck with what pressure you had already built up in the front brakes and trying to give them more will result in allpying the rears as well.

 

Why would I want to hold the brakes harder? If you step on the brakes hard enough the first time before setting the line lock, the front brakes will hold just fine in the water box. If you start rolling out of the water box, your front brakes must be shot or you didn't step on them hard enough before setting the lock.

I used to have the button on the tee handle of the shifter. I switched handles to a plain ball but still needed a switch for the line lock. A simple momentary toggle switch on the dash now works fine.

Pull into the water box. Start in first gear. Push brake pedel then hold down switch on dash. Start burnout, release switch, reach down to shifter and shift to high gear (powerglide). Line lock is released and I start to come out of the water box with about 100 mph wheel speed. That's all the burnout I need. Start to finish and it's over in about 15 seconds.

 

Mine won't hold the pressure backwards.

 

So how easy are the Biondo units to install? It goes between the master cyclinder and the combination valve, for the front brakes, right? The 2 brake lines from the MS to comb valve are real short, so where exactly are you mounting the Biondo unit?

And I assume you wire the toggle in series with the pushbutton, to be used as a manual enable switch? Just so you DONT accidentally hit the pushbutton (ie on the shifter) during everyday street driving?

Gonna half to get one ordered!

 

I've got both of mine mounted on the driver side strut tower towards the front side of it, and yes the inlet side of the solenoid gets the line from the prop valve and the outlet side gets plumbed into the front brake line T.

Wiring is just like you described

 

There are a couple of ways to plumb it but only one way is offically recognized by NHRA and IHRA.

The line lock must be plumbed after the combination valve.

The combination valve has 5 lines on it. 2 inlets from the master cylinder. One for front and the other for rear brakes.

One outlet goes to the rear brakes. The other 2 outlets go to the front brakes.

To hook it up properly, One outlet on the combination valve is plugged off. The other outlet goes to the inlet of the line lock. The outlet on the line lock is tee'd for both front brake lines.

Many people will try a shortcut method of installing the line lock on the front brake line on the inlet of the combination valve. Although this will work, there's no guarentee it will get past a tech inspection.

Always use a momentary switch so that you need to physically hold the switch on. A seperate toggle switch isn't needed. Pushing the button while driving does nothing since there's no brake pressure in the lines until you step on the brakes. It only works when you step on the brake to apply pressure, then push the button to electrically hold the pressure in the front brake lines as you take your foot off the brake. When you release the switch, pressure is released.

 

Huh… is there a reason? I can’t think of a good one. For that matter, I don’t know that I’ve ever seen one run like that… I know that all of the install kits that I’ve ever seen run it between the MC and the combination valve or the MC and the ABS box…

 

Any pics? I'm slow.

 

i thought i remember reading on here that the front brakes recieve full pressure, the only reason they go through the proportioning valve is for the warning light? can someone confirm this? i would like to do away with it since im running a wilwood valve, and i heard ls1 masters have the fitting for the warning switch in them, and i know somebody on here swapped one, but i need to confirm that too

 

the Biondo one works great...

along with my line lock, i used a wilwood prop valve... so i was able to cut and modify the stock combo valve bracket to mount the line lock.. looks MUCH better in real life.. looks kinda crooked in this pic, but its not....

 

Rear drums require a check valve, which is in the combo valve. I wouldn't eliminate it, personally (went through all sorts of pain with the '57 last season because of that).

 

i donno much about modding drum brake systems... i always swapped my cars over to disc before i started modding the rest of it for performance.... do thoes wilwood check valves work as a good replacement if you're removing the stock combo valve?

 

yea, the combo valve has a piston in it that slide all the way over triggering a switch if the pressure drops on either side. The cool thing about that with the line lock installed in front of it is that with the line lock turned on your dash, brake light will light up till you reliese the line lock. GM built in an indicator light for your line lock

 

Well, looks like there are several ways to install a line lock. I'm guessing not all cars came with the comb valve, so that just makes it more complicated. I was hoping the Biondo unit had 2 outlet ports, one for each front brake line, but looks like only 1 outlet.

I also have a Summit cut-back valve in my rear brake outlet line. But I dont want to get rid of the comb valve. It has a purpose. My mechanic was worried that if you block off one outlet of the CV, and go to the linelock, then out to a T; you might not get full brake fluid to the front brakes. Or at least full flow/pressure. You dont know what is going on inside that valve. He recommended putting it between the 2 parts.

My order is going out soon.

 

I understand your concern about plumbing it, but for a reality check I've got one port on my proportioning valve plugged that went to the front, and solely use one port that comes from the prop valve then into the line lock solenoid, outlet to a T and then to each front brake.

I can easily make the first turn off after trapping 120mph and this is with a now 3600lb car...with stock brake set-up, so if you/your mechanic buddy are worried about less stopping power....LOL, believe me, it's not an issue.

 

Not run "legally" but works well. The hurst unit here does have extra ports to run both front brake lines off of it. And I do like the fact that I didn't have to wire up a light.

83 Crossfire TA, any reason you can't left foot brake it to build more boost? This is in the auto car, correct?

 

Sure, but right now the car won’t even hold 1200rpm without the turbo on it, so it’s not like it’s going to hold much boost as it is now.

When it comes down to it I’ll probably just copy your setup but make mine a little prettier.

 

Why not try hitting the linelock and then the brakes. Will lock the rear ones down as hard as possible. That or a transbrake

 

Yea, I need more help breaking driveline parts…. Actually, tim, do you or anyone down your way know of any good deals on a tranny that will hold up to the abuse that I’m looking to dish out with this thing, even a stockfish TH400 should work…

 

If it’s plumbed into the rear brakes, but the fact is that the proportioning valve limits the upper pressure limit going to the rear brakes, which is why I would try to bypass it… the GN guys traditionally would swap their rear brake cylinders with larger ones just to get more braking force at the rear to launch harder…

 

brakes (hydraulics in general) are not about the cross sectional area of whatever connects the 2 cylinders at either end together. You wouldn’t be limiting your stopping force at all doing it that way, hell, that side of the combo valve is being fed by a single line so using a single line out will give you the same minimum cross section.

 

any of yawll have the thread size for the master cylinder and proportioning valve?