[slowbird]

Originally Posted by steve25

Just wondering here, how many folks commenting on this string have a flow bench at there disposal full timel , raise your hands!

So only people with flow benches can post?

[PAUL K]

Originally Posted by steve25

Just wondering here, how many folks commenting on this string have a flow bench at there disposal full timel , raise your hands!

Do you mean "full time" as you use a flow bench forty hours a week developing flow improvement or "full time" you have easy access to one but don't do performance cylinder heads for a living?

[Jay S]

Originally Posted by PAUL K

Do you mean "full time" as you use a flow bench forty hours a week developing flow improvement or "full time" you have easy access to one but don't do performance cylinder heads for a living?

I be in the second category with our own bench, brother an I built it while going through engineering right after I took a ME Fluids class in the mid 90s. But I take a head to someone else every once and a while to make sure our bench does not have some critter living in it. Lol. Gets used in streaks.

Out of curiosity, has anyone one here tried 8mm valves in cast iron Poncho heads yet? Or flowed the 30* backwards against 45* or 50*’s in cast iron heads..What percentage did the 45s change for reversion?

In regard to what 30* bring to the table. I have seen some “experts” not in the Pontiac world widen the LSA 2 to 4 degrees with 30* intakes. So if the experts are right on that, 4.5” stroke, 112 lsa and 30s? 70 cc head with a 30 cc dish? How big a dish can you get? Won’t a 30cc dish going to be 10:1 with a 670 head and that big arm???

It will be cool if you can make the 670s work for this. I like it, coloring out of the box

[Skip Fix]

I have a fixed orifice in the garage.

FWIW my RAIV heads exhaust port flowed 90% of it's flow backwards (85% normal E/I)pulling in it like it was an intake. Why we had some reversion issues and did header size and cam changes on it.

[steve25]

Just in terms of when you want or need it , it’s there to be used.

[KEN CROCIE]

Pontiac used a 30deg seat because all but 2 of their engines had .0406" lift. Geometrically, this exposes more exit area for air to exit the port.

[lust4speed]

When I first did my 670's back in the mid 80's I did have access to a flow bench and operator. He was another one of those aerospace engineers that quit and opened up his own shop. We never did a comparison between the 30° and 45° intake because to him the 45° was a done deal. For that matter he said a steeper angle would be better but for my then street/strip use the 45° was the best compromise because of the shorter life of extreme seat angles. Back then I was running a solid roller with .660/.666 lift on the street and it made excellent power, but never did the comparison against the stock seat angle.

I guess what we need is one of those guys with a flow bench to grab a garbage 670 head and port an intake with the 30° seat and flow it; then go back and cut a 45° and after appropriate blending do another test. Hey, it's for science.

[steve25]

I have a 670 head that I will donate to that cause and I should have the time to spend on that in the next 2 weeks or so.
I will even do a reversion test as the porting with the 30 degree seat ,

[lust4speed]

That would be great. I'll postpone the trip down to Flow Technology.

[Half-Inch Stud]

You can make a runner mold with uscomposites 64-30
So you measure CSA along the runner, to know what needs ground away.

[77 TRASHCAN]

Originally Posted by lust4speed

That would be great. I'll postpone the trip down to Flow Technology.

Off topic, I guess you know that Jim Hand bought a 65 wagon, brand new! He had a family, the wagon had a higher performance engine in it, can’t remember which one.
Jim’s nephew, Mike Little currently has a 65 wagon he brings to Great Bend, Kansas to the event held in the fall. Jim had to scrap his 65 wagon in the end, due to rust, so this is not the same car. Has a modified 455/TH400 in it, has gotten into the 12’s. Man it weighs 5000 pounds!