I would not use an MCA-Jet head, but that's just me. Agree on the match-porting. Might want to investigate induced turbulence techniques on the intake side, since you lose swirl without the MCA jet. I don't know what's available for matched valve springs in the 72 - 80 lb. range, but that's worth investigating. No MCA, plus a bump in the spring-rate should up the red-line usefully.
The 30-over pistons I got are better than stock. I don't remember exactly ... seems like around $100 for the set?
I already have a non-jet head on it. The factory jet head had several cracks in it, so when I took it to the head shop here in Nashville, he sold me a rebuilt non-jet head but I forget what he said it came off of. I've been running it for a couple of years now.
Did a little research on induced turbulence. Interesting concept. I see where it is being done in the combustion chamber, but not on the intake side of the manifold. Do you have any links or hints on where to go to see more on this idea?Originally Posted by manorchurch
I googled to try and find what I originally read about it, but no luck. At the time, I had included "Dodge" in googling, since I have a Ram 50 truck. Anyway, a while back I turned up a cylinder polish/port article written about a Dodge 2.2 engine -- I think it was the one in the old Neon? This guy uses a die-grinder to carve parallel grooves in the intake manifold in front of the port transition area, which, like you might figure, disrupts the laminar airflow and tumbles the mixture into the cylinder. Made sense to me -- moreso than just polishing the surface to increase flow and count on piston dome or other surface to make turbulence. This was turbulence specifically, not "swirl". Also, you only need to do one surface of the basically 4-sided intake port -- this guy had done some analysis that showed how the airflow follows the channel and sticks to one side.
Here's another wrinkle: he filled the upper valve chamber (the stem recess) with epoxy (not totally, but at least half) to increase velocity -- and volumetric efficiency (I assume). I forget what he did to prevent stem binding on the epoxy, but it was an interesting idea.
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