Ported Chevy 781 heads

[Carnut1]

Carnut, I might make a 1/2" thick plexiglass plate to send with this that you can sandwich between the head and the bench, with a 4.310 bore that has a chamfer on the intake side to match the combustion chamber-just to simulate my block. If you think this will work?

My bench has a 4.3" bore adapter now. Send it along if I can use it I will.

[Adger Smith]

Carl, I've seen several good Super Stock class BBC heads that had a small epoxy dam on what we call the bad port SSR to induce the floor bias and swirl .
Don't let those bad ports fool you!!
OH, you ask where I saw them?
How about NHRA tear down for setting records.

[In-Tech]

Carl, I've seen several good Super Stock class BBC heads that had a small epoxy dam on what we call the bad port SSR to induce the floor bias and swirl .
Don't let those bad ports fool you!!
OH, you ask where I saw them?
How about NHRA tear down for setting records.

Yes sir, amazing what some epoxy can do. Kinda funny the "bad" port design...hmmmm anyone look at the LS port

[Adger Smith]

Look at the splayed valve V-6 I run. Humm! Same bad ports (all 6 of them)!

[In-Tech]

Ya, stupid engineers making bad parts I thought I was wrong once but I was mistaken.

I hope the typing comes off as facetious

Code: Select all

fa·ce·tious
fəˈsēSHəs/
adjective
adjective: facetious

    treating serious issues with deliberately inappropriate humor; flippant.

Sometimes typing on the interweb is like wetting your pants while wearing a dark suit, you get a warm feeling all over and nobody notices.

[Adger Smith]

Where is the "Like button"??

[Carnut1]

Carl, I've seen several good Super Stock class BBC heads that had a small epoxy dam on what we call the bad port SSR to induce the floor bias and swirl .
Don't let those bad ports fool you!!
OH, you ask where I saw them?
How about NHRA tear down for setting records.

Yes sir, amazing what some epoxy can do. Kinda funny the "bad" port design...hmmmm anyone look at the LS port

In the 90' Chevy built a symmetrical port head. All bad ports. Funny.

[Bob Hollinshead]

Carl, I've seen several good Super Stock class BBC heads that had a small epoxy dam on what we call the bad port SSR to induce the floor bias and swirl .
Don't let those bad ports fool you!!
OH, you ask where I saw them?
How about NHRA tear down for setting records.

I'd like to see some pics of that epoxy dam, know of any? I would guess the dam would favor the cylinder side of the port to promote flow on the cylinder wall side?

[Adger Smith]

Are you kidding I would have got my butt kicked by the owner if I took out my phone and took a picture...

[rapidride2]

Im enjoying this 781/049 thread. I love the sleeper side of these heads.

[Carnut1]

0229161759.jpg

On youtube somewhere is an old 396 Corvair convertable from Long Island. These 781's came off that 396. Cut for 2.25/1.88 valves. I had no 2.25 valves in stock so I tested with 2.3 valve. Valve job is very thin with nearly no 60 degree cut.

[Carnut1]

0229161800.jpg

[Carnut1]

0229161853a.jpg

[Carnut1]

0229161853.jpg

[Carnut1]

0229161856.jpg

I think these have less metal removed than first set.