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JFairman JFairman is offline
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Join Date: Jul 2006
Location: S. Florida
Posts: 7,289
I don't have the spare $ to take them up to Xtreme and have them do anything more to them. I did a little more with the sanding cones after I took the last pics yesterday and I'm basically done with the porting. There is just a little minimal sanding cone touch up to do here and there for my own visual satisfaction.
It would be interesting to have them checked on a flowbench but thats expensive and they look really good to me. They will have a big improvement of flow in the 3500-6800 powerband rpms with my 964 cams timed at 1.26mm intake valve lift at TDC (overlap) before the intake stroke compared to the stock 32mm ports.

I carefully stayed away from the valve seats with the grinder and sanding cones so two layers of masking tape there worked OK for me. Gaffer tape or even duct tape is tougher though so that would be better.
The pieces of rubber hose on the valve guides worked great at protecting the valve guides. Porting should be done before new guides are installed but new ones were already installed when I bought these heads.

Getting all heads to flow perfectly equal on a flow bench while an intake valve is in place and open a certain amount would be optimal for a race engine with 6 individual throttle bodies but for a street car engine with the pancake mainfold I wouldn't notice any benefit.
The 930 flat pancake intake manifold I'm using doesn't come close to equal flow to each intake port and from what I've read the Carrera manifold doesn't either but of course it's better than a 930 manifold.

This isn't the first time I've done this and what I've done on my limited budget gives me satisfaction and is good enough for me. After final visual and feel with my finger inside the port touch ups I'll hand lap the numbered valves to the valve seats and put them back in a box and store them.
I also have new Mahle 930 3.3 pistons and cylinders from a sealed box, Glyco rod bearings and small end bushings, and ARP head studs I bought 5-6 years ago.

Maybe next winter when it cools down I'll redo the top end but for the rest of this summer I'll just enjoy driving the car with the AC on.
Old 06-21-2013, 06:46 AM
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