What size/thread count are the brake lines at prop valve?

[71Malibu402]

I'm installing a line lock on an G body Regal (1987 model) and I want to do it so it's NHRA legal. Which means I have to install the line lock after the proportioning valve and just before the wheel calipers.

My prop valve is the brass one and it appears to use some type of metric threads, hence the fittings they say to use in the line lock install instructions are incorrect.

Anyone ran into this problem? What size body/thread count do I need?

Thanks in advance.

 

[383S10]

Re: What size/thread count are the brake lines at prop valve

I believe the thread count is 18...... I ran into this problem with the wheel cylinder when installing stainless steel lines on my rearend posi...... I bought from Earls their brake line adapter fittings for GM app......

 

[71Malibu402]

Re: What size/thread count are the brake lines at prop valve

Thanks. Would you happen to know the body size?

 

[383S10]

Re: What size/thread count are the brake lines at prop valve

Okay I went into the gaarage and found the Earls packaging the brake adapters were -4 to 3/8-24 IF (pn 591982ERL) and the thread I quoted was -6 to 5/8-18 which they list as a power steering fitting but I used it as a adapter (pn 991947ERL) for my mechanical fuel pump to hook up my stainless fuel line there to the carb........and FYI if you can get the fittings in the brake adapter pack they come in pairs and are cheaper than buying the single packs mine were $9.50 for the pair price and the single was brake line fitting was $6.95 per pack.........