HV-12 Rebuild: Chevrolet Exhaust Valves

[MNathan]

 

Anyone ever followed advice in Jake Fleming's The HV-12 Rebuilding Bible related to substituting Chevrolet Exhaust Valves in their rebuild?

I have a print of the article from the LZOC and in the follow on FAQ a fellow named Les Keeton suggests that even though they are a tad longer, they are a better quality valve. He provided guidance to stem height for hydraulic lifters and 1 piece guides. I plan to use solid adjustable lifters on an isky cam.

 

The clarification I need, is that he directs one to use the "1st valve keeper groove" and references a photo that is missing from the print. As the Chevy valve has a 2 groove keeper, I am looking to his reference as "1st groove" being the top or bottom groove on the Chevy valve?

 

I guess experimenting with installed spring height and seat pressure may tell, but I need to know before that stage, as there are a lot of inexpensive performance stainless steel chevy valves with smooth stems and swirl polish to improve flow of the small V-12 ports, and most of

the performance valves only have a single keeper groove.

Edited April 24, 2021 by MNathan (see edit history)

[cdan34]

On my v12 I used Chevy valves that were 1.550 dia. The valve inserts will stand the bigger size. May be even let more fuel in. I had to machine a small amount off the stem

and use special valve spring lock which lowered the spring height. All this worked well with Johnson adjustable lifters and reground cam. I used the single valve groove and the valve locks I purchased at Speedway Motors.

[MNathan]

cdan34, which valve locks did you use? Ford or Chevy?

Edited May 6, 2021 by MNathan (see edit history)

[cdan34]

MNathan, The valve locks I used were from Speedway Motors part # 91599097. As you mentioned they were for Chevy Exhaust Valves, single groove. I forget the amount I took off the bottom of stem, but it worked out well with these valve locks.