power brake conversion kit question

[Jayschevy]

I got a new power brake conversion kit form Brothers Trucks. My question is where on the top of my engine do I connect the boosters vacuum line too? I'm not sure which lines are vacuum lines. Any help would be appreciated.

Thanks

[Wrenchbender Ret]

It depends on what engine & carb you have. The v-8 s have an opening on the intake manifold behind the carb. You can take out the plug & put a fitting in. The 4 barrel carbs have a plug or tube on the rear lower part of the carb. The 6 cyl.s have a plug on the side of the manifold or on the rear runner to 5/6 cyl on the manifold.

[jocko]

Jay, Wrenchbender's correct. There is one thing that is important in choosing a line, and the big one cominng off the back of the carb will usually be the right one - but you need to ensure it's a "full time" vacuum line, and not a "ported vacuum" line. If you have a vacuum gauge, it should show 16-ish or higher inches Hg at idle (this would indicate that it's a full time port). The other way to tell is if you pull the line off and cover it with your finger, you feel it sucking at idle, then you should be good.

Generally speaking, it's almost always going to be that big one coming off the back of the carb - or if it's plugged, that's where you will need a fitting and/or new hose.

If you take a pic of the front/back/side of the carb, someone will quickly point out which one to use.

[Jayschevy]

Thanks, found it. The fitting was on top of the manifold near the back.