1971 Buick 455 GS F/SA G/SA Build

[HP HUNTER]

Thanks for the nice comments. Lets talk about valve guides and valve jobs. These particular heads utilize bronze knock in guides, the guides are bought with the ID .370 (undersize) the guides are installed which distorts the ID, I then cut a carbon relief slot in the bottom of the exhaust guide with a .450 reamer .125 deep. I use carbide core drills (similiar to a K Line core drill) which I had made, the guide is drilled to .3715 making it strait and round, the guide is then honed to final size with a Sunnen hone with Sunnen hone oil. You now have a perfectly round and strait guide, which allows you to cut a perfect seat. A perfect contact patch on the seat allows you to transfer the heat in the valve to the valve seat.

Rich.....I know you like this stuff, ck out this link

http://www.chevelles.com/forums/13-p...-pictures.html

Look closely at the valve contact patch (lap lines)

[Rich Biebel]

" I then cut a carbon relief slot in the bottom of the exhaust guide with a .450 reamer .125 deep."

You lost me on the above operation ? A picture is worth a thousand words.

Practically all the head work I did over many years was without the use of a seat and guide machine. Benchtop operations.....hand held drills and tooling.

I did buy out a machine shop in the early 1990's and that buy included a Kwik Way 019 S&G machine. I did not use it much. Eventually sold it for a giveaway price.

Nice work on the BB heads and I hated replacing the stock guides in them. I would leave them and thin wall line them mostly due to the rediculous way GM factory drilled the guides off center from the seats on some. Also the potential water leak issue passing thru the water jacket.

I have taken brand new aluminum heads from the big name manufacturers with nice looking Serdi cut seats so far off the old valve bounce test is a NO bounce and just a thud......LOL

Bought a set of Darts for my own engine. Operator who did the VJ on them must have been drunk......had to use my old school stones to fix it.....Not fun but I make it work...

Your work is excellent.....

[HP HUNTER]

I finally got the exhaust side of my heads done. Although I'am not sure I have this right, so I have questions. On my BBC builds with conventional camshafts I've always wanted lazy low lift flow then have it come on after .300 lift and take off, this has always worked well for me. On my Buick I gained around 12 CFM @ .200 and 12 CFM @ .300 and about 10 CFM @ .400 and finally 9 CFM @ .466 peak lift, will this help me or hurt me?

[R. Thorne]

I almost didn't answer this because there's not enough info to make a valid response ( again, where are the .100 flow figure improvements on intake & exhaust). Also, i don't know what was done to improve the intake or exhaust flow. You are definitely going to have a (seemingly) wilder cam with low lift flow increase. You will have more reversion, true, but, in my opinion, you are going to see a substantial performance increase. Ron.

[HP HUNTER]

Originally Posted by R. Thorne

I almost didn't answer this because there's not enough info to make a valid response ( again, where are the .100 flow figure improvements on intake & exhaust). Also, i don't know what was done to improve the intake or exhaust flow. You are definitely going to have a (seemingly) wilder cam with low lift flow increase. You will have more reversion, true, but, in my opinion, you are going to see a substantial performance increase. Ron.

Ron, I will send you the flow numbers in .050 increments, I'm actually scared to to see the increase @ .100 lift on the exhaust. Intake to exhaust flow is roughly 67% @ peak lift.

[R. Thorne]

Sorry for delay, Mark. As Mike Taylor, Adger Smith, and others have said total and/or average flow is more important than peak lift flow increase at the expense of lower lift flow. I did not see anything exorbitant in your low lift exhaust numbers. Frankly, there is probably more potential low lift available. There are, of course, ways around the reversion issue if that is what concerns you, but I don't think you will need it. In short, yes, IMO, it will help you. Ron.

[HP HUNTER]

Heads are finally installed on the engine. I would not look forward to doing another set like this Now I've got to fit the intake which I could see taking a day to get a good fit, then its dyno time.