Don Terrill’s Speed-Talk

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http://www.fordmuscle.com/archives/2000 ... /index.php

Good article. Interested in some feedback from that in reference to these castings. Thanks, Charlie

Charlie,

Why were the old, "sparkplug trough", heads so bad? Like the old '56, 265", -306 heads combustion chambers.

pdq67

I have never worked on a set of those heads. 1.72"/1.5" valves I believe with tiny ports and a horrible chamber for flame front propigation. I would say not so great, can they be improved? Lots.

66 289 1.85" valve bowl progression. A bit bigger, ssr laid back more, roof raise a bit, opened pinch a bit. Exhaust needed to go to 1.6" due to some seats that would not clean up at 1.5".

Be very careful raising the roof too much on the cylinder wall side. I ruined a set long ago getting greedy there, it is pretty thin. I didn`t have a sonic tester though. Great work!

ozyfordman wrote:Be very careful raising the roof too much on the cylinder wall side. I ruined a set long ago getting greedy there, it is pretty thin. I didn`t have a sonic tester though. Great work!

Roof is still .2" thick. Using the sonic quite a bit since my last oh, no! Trying to get the best flows with a relatively small port. I have a feeling they will still wind up about 150 cc. Thanks, for the kind words.

Carnut1 wrote:20170730_181250.jpg66 289 1.85" valve bowl progression. A bit bigger, ssr laid back more, roof raise a bit, opened pinch a bit. Exhaust needed to go to 1.6" due to some seats that would not clean up at 1.5".

Charlie, I just love you iron cutter work - it's inspirational and gives me a goal to aim for.
DV

The irony, me being an inspiration to you. I will give a detailed lesson next visit. Thank you

Not a great pic but interested in feedback on this string and what it tells us. Thanks, Charlie

I went through adjacent to the guide on the roof trying to get the bowl bigger on a set of C5AEs.These are very hard to find in Australia. There is water close by and it would be a difficult spot to probe. Wouldn`t you know it , it was the last port out of 16. Tried brazing it and made a big mess of it. Bought a set of Windsor seniors instead ( they were just out then) and went to town on them. I avoid iron these days, particilarly old castings. I admire your perseverance.

I am looking forward to some aluminums soon, thanks.

Carnut1 wrote:20170730_201921.jpg Not a great pic but interested in feedback on this string and what it tells us. Thanks, Charlie

What did you learn from that?

GARY C wrote:

Carnut1 wrote:20170730_201921.jpg Not a great pic but interested in feedback on this string and what it tells us. Thanks, Charlie

What did you learn from that?

I think it is interesting how the string shows where the air flows and sometimes the air turbulence. This was at .7" lift at about 217 cfm. You can see by the blurred pic that the string was moving up and down. Interested in what others think, Thanks, Charlie

I like this pic, little different starting point and the string is dead straight and the string hovers off the wall. You can actually see the airflow path. Thanks, Charlie