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« on: June 20, 2014, 07:52:05 PM »
With permission: I acquired a set of the BBM aluminum heads for the FE, and did a cursory valve job on a Serdi with multi-angle seats, back cut intake valve of 2.080", and custom radius exhaust seat with 45* valve face for a 1.600" exhaust valve. I went with these sizes to start off the flow expectation from smallest to larger on later tests. The guides were so hard that they had to be honed to size, since a reamer would not work well with the hardness. It took nearly 2 hours just to hone the guides to size for the 11/32 valve stems. Here are the flow values for the initial testing of completely stock ports.
Intake
.100 63.98
.200 136.09
.300 207.18
.400 234.61
.450 243.85
.500 252.79
.550 261.14
.600 267.10
.650 274.25
.700 280.22
.750 284.99
Exhaust
.100 52.00
.200 98.30
.300 129.99
.400 149.99
.450 161.98
.500 166.84
.550 173.32
.600 178.18
.650 181.42
.700 183.69
.750 184.66/2" pipe 200.86
Super Flo 600 #6729 @ 28" 70* 38% Humidity in airconditioned room, calibration check completed. The valve seats were proud in several ports, and the flow was noisy at low lifts. I am sure the exhaust will come up with larger size valves, as will the intake. This was just a preliminary test as cast with CJ size intake valve and a slightly larger exhaust valve than a standard 390. I will be testing with 2.100/1.660 next as time permits, and ultimately 2.190/1.710, and then fully hand ported. Since many have followed different heads' flow sheets over the last several years, it will be interesting to compare on the same machine with same operator, and same porter. As always, I just post what I get on my machine as truthfully as possible and under as similiar circumstances as possible. Joe-JDC
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