Don Terrill’s Speed-Talk

Unity video ties it together.
416ci
Cam is NLA BTR 239/254 .631/.610 114+3

They cut the AFR heads to 62cc, don't know if they were flowed before or after. 72cc from AFR ?

Wrong heads for that motor anyways.

Big ports don't need big cams. DV showed us nothing again. No but the AFR has a smaller intake. But by his measures the head with the smaller intake valve has the potential to move more air. And it did at lower engine speeds. I wonder whether it's the old flow bench doesn't pull as hard as a high r...

mt-engines wrote: ↑Mon Apr 22, 2024 8:38 pm

Tom68 wrote: ↑Mon Apr 22, 2024 7:34 pm Standard cam for DV's?
Then it's all about curtain area.
Both the ports are probably too big for a small cam.

Big ports don't need big cams. DV showed us nothing again.

No but the AFR has a smaller intake valve.

Standard cam for DV's?
Then it's all about curtain area.
Both the ports are probably too big for a small cam.

Smaller valve head made less top end more bottom end, no surprises there.
Same thing a month earlier.

AFR may have to get on the front foot with this one and explain what the head is meant to do.

F-BIRD'88 wrote: ↑Sun Apr 21, 2024 10:00 pm

On that single plane it will benefit from a plenum divider. Whether the plenum divider needs to full height isolating the left and right side of the plenum completely

Yuk.

Cheers, looks like this is an Aussie only version, quite a bit different to the US one.

I have two, they were assembled one each way.
I have two pics off the net, same thing.
It does matter, there's a piston in the piston.
I'm too lazy to work out how it works to then decide.

Blocking the exhaust crossover... Hmmm... IF I am not mistaken, years ago in school they said that reduced combustion chamber temps to reduce NOX. But yes, that would indeed heat up the intake manifold. I am interested in hearing more about plugging this rather if I do it or not. What, the passage ...

First of all, run on or dieseling is caused by throttle blades open too far at idle given all else is correct. Dieseling is auto ignition, injected motors don't get it because the injectors are shut off. The thing that was most gruesome in the test was when Brule went to shut the iron headed engine...

Remember that the length of the TPI doesn't make it want to rev. No need for more than 1.94-1,50 valves with TPI. Erland You still want to fill the cylinder at any revs, TPI won't like long duration cams either so area will help. Just no point running 2" + if you don't enlarge the runners.

No tricks required.

A low power 302, you could just get a 305 or better still a 307.

Carnut1 wrote: ↑Sun Apr 14, 2024 6:58 pm I feel in order to increase mass flow the csa has to go up around turns. What this does to the resonance I am not sure. Thanks

It will at least be more important than the resonance.

Furnace cement isn't it ?