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Also got my RTC 6 head done today . Got the porting done , I have pics but they don't really show the work to the short side and port floor work . I don't reshape the ports or enlarge them , just smooth them out .
From what I read on BOBs 4cycle those guys say not to enlarge the ports , but to take out the ledge on the port floor . Which is what I did we now have a round transition the is blended in to the valve seat .
When you stick your finger in the port there is normally a sharp edge on the short side , that's the area the needs the work .
I also blended and smoothed the area around the valve guides and the wall area into the bowl .
From what I read on BOBs 4cycle those guys say not to enlarge the ports , but to take out the ledge on the port floor . Which is what I did we now have a round transition the is blended in to the valve seat .
When you stick your finger in the port there is normally a sharp edge on the short side , that's the area the needs the work .
I also blended and smoothed the area around the valve guides and the wall area into the bowl .
More pics
I also milled the thing I think 30 thou but not sure . Took a measurement from a point 291.65 and sanded to 288.30 . Right now the plug just hits
the piston without a gasket . I went with a stock length rod so I'am now 21 thou in the hole . The plug can have washers put on it to raise it up .
As long as I have about 25 thou between the piston and valves I'am good . Hell maybe some more milling .
I also milled the thing I think 30 thou but not sure . Took a measurement from a point 291.65 and sanded to 288.30 . Right now the plug just hits
the piston without a gasket . I went with a stock length rod so I'am now 21 thou in the hole . The plug can have washers put on it to raise it up .
As long as I have about 25 thou between the piston and valves I'am good . Hell maybe some more milling .
Clone nail head short side radius.
If you look at a tipical wedge head, the small block chevy for example, you will note that the short side radius of the intake port, for the most part, dumps into the centre of the bore, the cross flow nail head your playing with does not employ this tactic, the short side has to flow on the wall side of the bore.
With out a radius as is stock form, flow is probley near net zero, with a radius and lots of valve lift there will be some flow but for the most part only at low port velosity.
The Hemi with its canted valves attempts to fix this problem and gain flow on the short side at higher port velositys.
The best solution that i see to this heads poor port design is run extreme lift and give the port a strait shot at the bore. .308 if you ask me is just a minimum.
If you look at a tipical wedge head, the small block chevy for example, you will note that the short side radius of the intake port, for the most part, dumps into the centre of the bore, the cross flow nail head your playing with does not employ this tactic, the short side has to flow on the wall side of the bore.
With out a radius as is stock form, flow is probley near net zero, with a radius and lots of valve lift there will be some flow but for the most part only at low port velosity.
The Hemi with its canted valves attempts to fix this problem and gain flow on the short side at higher port velositys.
The best solution that i see to this heads poor port design is run extreme lift and give the port a strait shot at the bore. .308 if you ask me is just a minimum.
great job on the head... porting looks nice... i was thinking about working on another head too, a zh8 i had sitting, pulled off another... just do some minor porting and put together a motor with used parts... i have a few used engines i picked up here and there to practice misc stuff... soon as i get my garage in order... working on that... will be go time..
i cant wait to hear your motors fire up, your builds inspire me...
i cant wait to hear your motors fire up, your builds inspire me...