Bobby asked me to post some updates on the porting of the heads for KnightMoves.
Last night I flow test a port in the test head. It flows very well, but it is NOISY... I think most of the noise was coming from casting defects under the seat... Some may be coming from some awkward transitions in the port itself.
I took an initial stab at porting. I reworked the bowl and cleaned up the transition under the seat. As a result the port quieted down and picked up a significant amount of flow!
There is a whistle that peaks around 0.030" lift. I think it is caused by the shrouding of the valve. Since Bobby is looking to decrease the compression ratio some, I will unshroud the valve to try and cure the whistle and further improve flow.
I also need to do a little more work on the short-side radius. Stock the SSR looks "lumpy" and protrudes into the port too much.
Bottom line, stock there is a lot of flow, but there are a lot of gains to be had in flow quantity and quality.
The big difference I noticed so far between the SOHC and DOHC
6G74 heads, the DOHC
valve heads and stems are larger...
3L V6 Guru and all around FWD Mopar fanatic
'91 Dodge Spirit R/T turbocharged 3L V6, exhaust turbo header, ported intake, stage 2 ported heads
'87 Dodge Shadow turbocharged 3.5L 24-valve 6g74. 12.3@122