Don Terrill’s Speed-Talk

If you are doing this on a dyno I would suggest hooking up a knock sensor and TDC sensor to an Oscope. Knock is quite easy to see on a scope on the dyno. You just look right after TDC for noise. You will see the amplitude increase when it knocks. All those silly boxes are just noise threshold boxes ...

David I would prefer to use an air spring actually. Just like F1

Well if it bounces off the seat you lose cylinder pressure
If it floats off the top of the lobe you gain cylinder pressure
Not a hard one to figure out.

It was probably a brazing rod.

"Except that if you use an aftermarket pulse-width modulation system, it won’t work reliably"
How can't it work reliably unless you are picking the wrong SSR or something?
This literally cost a whole 35 bucks to do if your ECU can accommodate and is 100% reliable..

Guys Bosch 044's get noisy as hell also when you get the fuel hot. The key to using a high flow after market pump on the street is to pulse width modulate it at low demand so it flows less fuel keeping the fuel in the tank cooler.

I would bet that your valve seat moved in the head and you had very tight clearances in the valve guide. It appears to have broken off at the end of the valve guide due to side loading. Probably had an inclusion in the stem and the side loading exacerbated it.

Erland do you put in a thicker seat so that you can get a good 30 and 60, 75 cut on them to aid in airflow?

Brian P if you are forced to run at 14.7 AFR you are leaving 15% more fuel on the table. That is significant.

Yes the stupid emissions have been killing fuel economy for quite some time now.

If you want to do steel on steel you better have a PHD in tribology. Why re-invent the wheel. If shit works leave it alone.

Do any of you guys run narrower than the standard .060, .050 inch 45 degree seat width on small valves? Like in a 4 or 5 valve per cylinder head?
When I do my 5 valve head it hardly has any 30 or 60 degree width.

VE is most definitely not massflow.

VE is NOT king.
MASSFLOW is the king...

Air Chisel with the big round flat tip. Hopefully they didn't weld themselves together.