[dataway]

Yep, I used Ferrea in all my vintage race engines for bikes, always performed beyond expectation. ... Well ... I used Ferrea intake and Manle exhaust due to special circumstances.

[Rocky Rotella]

Is it absolutely certain that original R/A IV intake valves are two piece? The head received an aluminized coasting but the entire valve should be 8440 alloy.

Exhaust was definitely two piece.

[Half-Inch Stud]

An engine expert said meh about my Ferrea valves, and really had a don't care about the valve weights or materials when i showed the Titanium intakes, and RA-IV valves. BECAUSE my engine application is limited to < 5500 RPM.

His eyes (as were mine) were more on the backside shape, for best valve curtain upon opening. Ferrea & Ti-alloy have the best low-lift valve curtain. RA-IV intake is a sunk valve by comparison.

As for the spare engine going Roller cam and high rpm; Pick valve having best flow at mid-high lift, without turbulence ( or flow choke evident by the numbers).

[gtofreek]

Originally Posted by Rocky Rotella

Is it absolutely certain that original R/A IV intake valves are two piece? The head received an aluminized coasting but the entire valve should be 8440 alloy.

Exhaust was definitely two piece.

I'm almost certain they are 2 piece. From a manufacturing standpoint, it is far easier, and cheaper to make 2 piece valves. 1 piece valves take special tooling dies and process to forge. 2 piece are much easier to make a head, then weld it to a stem. 2 piece valves always have a slight bulge at the base of the stem where it is welded together. If the head appears cast on the back side, instead of machined, it is a 2 piece valve.

[grrrrregg!!!]

ok, I tried the magnet thing this morning. Intake- magnet stuck everywhere on the valve. Exhaust- magnet stuck to the tip of the stem and nowhere else.

[Formulas]

I have in my hand a original tulip ram air 4 valve both the stem and head are attracted to a magnet however these particular valves are very clean and polished and I can see a visible difference in color between the head and stem the head is a darker in color and you can feel a small step at the color transition p/n on stem is 9794021

[Formulas]

Weight... Tulip that has been dressed once is 128g's and a new nail head is 145g's... The nail head is for #48 heads = shorter

[Skip Fix]

Mine came bare so no factory valves for me to check. I bought a set of Childs Alberts SS(made by SI) that have some of the tulip but TRW SS D port flat valve in it flowed better.