Ported Ford 289 heads with port energy discussion

[Carnut1]

Getting to the finesse stage of these and comparing the flows to DV's E7TE heads these match the high lift flow but get beat bad from .4" and down. I may use DV's modern vj, still deciding. These will get about a .6" lift cam. I have not been given permission to discuss the valve job layout but I am interested in opinions. 38, 45, 60, 75 blended to bowl valve job now. Thanks, Charlie

[mag2555]

What is your current valve to Throat percentage Charle?

Also if the heads are on the edge of going into tumble, adding more low lift will increase the TOTAL air mass and that may be enough to take the velocity to the edge!

[Carnut1]

About 90.5%

[BILL-C]

Charlie, have you tried a few different intake valve head shapes and back cut stretegies?

[Carnut1]

Charlie, have you tried a few different intake valve head shapes and back cut stretegies?

I haven't, I may have some 1.94" intakes for experimentation but I am time limited. What do you suggest? Thanks, Charlie

[mag2555]

The angles I use depends on how stable the flow is at high lift.

If my Intake port at max lift is showing signs of pumping on the Manometer I will not use a 75 degree blend cut because what's called for is away to trick the short turn into thinking that's it's higher than it is.

I do this by taking the metal on the short turn that would have been the blend cut and grinding it straight / parallel to the valves inclination angle.
After this I may also have the option of laying back the short turn more and even gain 3 or 4 cfm in the process.

If I am looking to get 30/ 45/60/75 angles inplace then I concider 89 % the max if the heads will ever get a freshen up valve job down the road.

[BILL-C]

Try as many different shape, back cut, and margin thickness valves as you can.I have been surprised by the difference between the best and worst. I haven't used a 1.94 valve in those castings before, so i don't have an answer on best combo. Everything that i build HAS to be absolutely reliable, even if we leave a little power on the table.

[Ks Fats]

Charlie,
While I have not worked with that particular casting when I put 1.94 valves in the 520/896 s.b.c. castings I found more flow by turning 2.02 valves down to 1.94. I attribute this to the poor margin on the 1.94. Turning down the 2.02 allowed me to tailor the margin width and form a radius from the margin to the valve face. A narrow undercut .030-.040 wide @ 37 degrees worked also. Another combination was to cut 1.94 to 1.875 and do the same thing; if your seats are cut for the 1.94 then the 1.875 is out the window but I have seen it flow equal to or better than the 1.94 in those castings. Not a ford casting (not an apples to apples comparison) so this is just a F.W.I.W. since you're in the test mode.

[Ks Fats]

Make that the head of the valve Charlie not the face; thinking one thing and typing another. That's what happens when old age has reduced you to having only two brain cells left and they start arguing with one another.

[In-Tech]

Charlie,
While I have not worked with that particular casting when I put 1.94 valves in the 520/896 s.b.c. castings I found more flow by turning 2.02 valves down to 1.94. I attribute this to the poor margin on the 1.94. Turning down the 2.02 allowed me to tailor the margin width and form a radius from the margin to the valve face. A narrow undercut .030-.040 wide @ 37 degrees worked also. Another combination was to cut 1.94 to 1.875 and do the same thing; if your seats are cut for the 1.94 then the 1.875 is out the window but I have seen it flow equal to or better than the 1.94 in those castings. Not a ford casting (not an apples to apples comparison) so this is just a F.W.I.W. since you're in the test mode.

Yepper, plenty of times take an older worn out large o.d. valve and trim it to size increasing the margin, then shape it. When Al was at Ferrea I really liked what he did with the high tulip heavy margin backsided exhaust valves. These kinds of things can really change what you think about the chamber. Then there's the weight

Anyway, good thread, I've been following it since learning never ends.

[Carnut1]

I decided to do a bit smaller throat ratio on the cnc head due to how thin my cutaway was right at the top of the bowl. Seems to have lost a bit of flow at every lift. Interesting.

[Carnut1]

20170717_203502.jpg

I was not happy with the flows being less at every lift point on the intake so the cnc head now has similar bowls to the other head. The ssr is less radial but not much it does have a bit more overhang into the bowl. I will reflow these this week if the garage is less than 90 degrees! Thanks, Charlie

[Carnut1]

Resized_20170719_182458.jpeg

Just about done on the cnc head. Pic with valves used in flow tests. 1.94" 1.6". DV asked to do the chambers a bit different. See who is sharp and can tell what it is and the logic behind that decision. Thanks, Charlie

[RevTheory]

Got it! Nice move, btw.

[Carnut1]

Glad someone got it.