Power brake vacuum source question

[Metalaroundstone]

I recently bought the stock power brake linkage for my 66 C10 and am getting ready to install it along with a new booster. My manifold vacuum fitting (behind the carb has two fittings, one of which goes to the transmission, and the other one is unused. Lucky! Unfortunately, both the fittings are 5/16", whereas the vacuum booster fitting is 3/8". Do I need to get a new fitting somewhere? Or is there some other way to deal with this difference? Does many body know how vacuum line was handled on an all original 327 with power brakes?

[DesertCat]

Just dealt with the same thing on my 67. My son found what we needed at Autozone.

[Metalaroundstone]

I sure didn't see anything on the Autozone website that would solve my issue. Maybe they have more stuff that they don't list.

[cortcomp]

You need some basic pipe thread fittings. You can get it from the manifold directly, or from the carb fitting, or put a 3/8 T behind the carb and reduce the 5/16 line, etc, etc. Get sone pipe thread fittings and do what looks good to you, as long as you have an always on non-ported vac source.

Lowes, auto parts stores, etc have them....pipe thread is always tapered.

[Rich 5150 69]

Originally Posted by Metalaroundstone

I sure didn't see anything on the Autozone website that would solve my issue. Maybe they have more stuff that they don't list.

Its in their self help isle, same with orielys or napa....or go to any wrecking yard...

[Metalaroundstone]

Originally Posted by cortcomp

You need some basic pipe thread fittings. You can get it from the manifold directly, or from the carb fitting, or put a 3/8 T behind the carb and reduce the 5/16 line, etc, etc. Get sone pipe thread fittings and do what looks good to you, as long as you have an always on non-ported vac source.

Lowes, auto parts stores, etc have them....pipe thread is always tapered.

Thanks for this advice. I found that I could get all I needed from Home Depot. But I also discovered that early Corvettes (64-68 or so) used a manifold fitting that I think is exactly what I need. I got it on Ebay for 8.99 and it included shipping. I hope it is as advertised. If not, back to Home Depot.