Don Terrill’s Speed-Talk

I was thinking more in terms of current engines. LS/LT, new Hemis.

Packaging from my own possible projects. A 90's 300ZX TT is a narrow angle engine . Even so, its a bunch wider and is actually a small amount heavier than a LS3 which in its more simplified N/A form is good for an easy 150-200 more HP. Any comparison will be different. But, in my case there's an obv...

The ports are generous. But, I doubt that's an issue especially considering the good flow rates. There are good performing engines with larger port (per valve area) that run fine. The mixture motion will be similar to a non-ski jump/tumble 4V head. The chamber is pretty snug around the valve offerin...

Nice to see an adult discussion on this. All types have strong and weak points. Matching the best compromise of these with requirements of a specific application is why they're all still relevant.

Grant, I still haven't found the test. But, I share your concerns with the area of the Speedmaster deal. It's been my impression that IR manifolds have more area at the butterfly than the intake valve to feeds. I'm still curious about this. I'm sure you're ahead of me on this. But, Holley has a &quo...

I'll try to find and get back tonight.

I understand the IR 8-stack intake by Speedmaster is a big boost over what you have . All I remember is 30-40 more peak HP with more everywhere. I think the closest intake was -30 to it. Several were tried. It was a milder engine than yours. A 40 CFM loss by adding the intake "concerns me.

A guy approached me in a motel parking lot when I was installing a starter on my car. He asked me "How many 32nds in an inch. i cracked up. He then told me of the 10 applicants applying to a machining class he was teaching 4 gave wrong answers. And, they wanted to be machinists! Our education s...

In a straight line all bets are off. I’m certain the Flathead would have been handed it’s lunch. In this discussion I’m getting more towards complete vehicle performance combining the aggregates of acceleration, cornering and stopping and even including the intangibles like being stealthy enough to...

I don't know. One round cylinder with two round valves. Not many layouts that weren't tried before WWII. a 26° intake vs. a 9.5° intake angle doesn't sound like they were following the same game plan though.

Even with the extra displacement the OE ports on a 426 hemi weren't as large as the 4bbl Cleveland or a rectangle port BBC. None of them had a good exhaust port.

RevTheory wrote: ↑Fri Feb 12, 2021 8:10 am Quick diversion: does anyone remember DM's preferred tulip radius on the exhaust valve or have a recommendation for a 1.5" valve diameter?

Nothing flatter than a 16° If using titanium up to a 30° normally works well. Might be too heavy in steel though.

Chad. It looks like the burr finish tightened up the the lowest to highest velocities. That, would help the incoming charge spend less time tripping over itself. That's a good thing. As long as the port is large enough to not become area restricted by the increased fuel vapor the engine would probab...

That Stude has to be the coolest car there. I never knew that combination existed. Love the plain look too.

Belgian, Sorry to hear of this stupid law. And, it all stems from people who don't know how to open their hood without the owner's manual feeling qualified to make laws over cars. These are some of those "feel good" laws that others who don't know how to change their oil support. They're m...