Venturi effect valve seat area

[agertz1]

Shrinking the exh. from 1.71" to 1.6". Making custom seats. Best throat dia. for a 1.6" tulip valve ? Stepped od. of seat can be as deep as needed,
for best venturi effect. Will need flow bench verification in Orange or Riverside Co., Ca. Suggestions ?
Thank You, Art.

[mag2555]

Is this a Ford Head?

[agertz1]

No it isn't.

[mag2555]

Flow bench test of tulip over nail head exh valves will always show a low lift flow gain and in fact a big low lift flow gain if the valve bowl is deep enough, but a number of times I have not seen that translate into a performance gain.

Are you shrinking the exh valve to facilitate using a bigger intake?

[agertz1]

Since 95% +/- street use, a .737 exh. to int. ratio will be an ok compromise. Married to unaltered Nascar valves,( 100% coated). The cfm will be
adequate, but will need velocity for street use. Looking for 1.63hp/in. NA on E85.
Thanks, Art.

[agertz1]

Married to unaltered/coated Nascar Ti valves, ( 1.737exh/int. ratio). Need suggestions for flowbench service in Orange/Riverside Co., Ca.
Thanks, Art.

[mag2555]

1.63 hp per cid tells us nothing without knowing the overall CID here and the max rpm!

Modern day Diesel electric locomotives with 16 cylinders and 710 cid per cylinder output 6000 hp, but they only spin up to 950 rpm for example!

[agertz1]

Ok my bad, that was discussed in " E85 Experimental". 43 cu. in. per cylinder. Air cooled cylinders,(4) with liquid cooled heads,(2).
I will require flow bench eval., next.
Thanks, Art.

[agertz1]

Also: using Ford 4.6L , 2 valve, finger roller rockers and dead end hyd. lifters. I suspect this valve train and engine, should live at 7,500.
Stroke is 3.288".