My First Shot at Porting Heads

"just put this in another thread.


The most common problem on all intakes which all overlook is port match not gasket match per say. Intakes ports are usually ported as per the gasket per side . But it is left bank to right bank that every one over looks. Scribe a line on the top of each intake port separator using a straight edge on the gasket side. Doing this will show you where th web between the two ports are after the intake is set in place. These lines should match centered with the valve cover bolt holes which are centered in the ports.

Wait until you all see how far off some of your intakes are. This is corrected by splitting the difference from side to side by moving the intake front or back. One reason after market intakes do not have the pin holes drilled. after you locate your intake put your pins back in an reset the intake back on in the corrected location .

At this time tap down on the intake ends leaving a marks where the pin goes and then drill them. This intake will always set where it is best aligned on that motor now. Once this position is found you can now port match the intake front or back to the corrected gasket location. This procedure means a lot when it comes to balancing cylinder charge at higher RPM's. which if not correct will throw the motor into a static vibration and cause power loss.

I shift my car at 8500 and it will climb to the end of a 10,000 recall tach. My Indy intake and heads were off almost an 1/8 of an inch. One reason a good sheet metal intake is built on the motor and heads it is to be used on. I learned this trick and others from Mike Dunn through Roland leong. AKA " Hawaian Punch" years back. Works for me.

This is why everyone has a different choice of intake and what works best for them . Some of the same intakes that are perfect on some motors but are way out on others. One intake two motors. two different locations. A used ported intake on one motor may not even come close to sealing on another.

When buying a older or used intake make sure it is virgin and never touched in the ports.

Now its time for you all to kick in with your neg. replys why this doesn't apply to you because your intake is already on and your car is perfect. But to some this may be helpful. "Happy Easter" Steve

Been a number of times someone has brought in a ported intake, just to find its off over an 1/8 inch or more. Makes me wonder how these pro porting guys can sell you a ported intake with out having the motor right there to go off of.