I was going to trim the towers on mine when I had the engine out this winter. Did some measuring a found it wouldn't help header clearance, at least not with my combination. You can only trim down to about 2" above the upper control arm bolts centerline. The point where the shock tower interferes with the headers is below the control arm bolts. Would've had to fabricate the lower part of the towers and the engine mounting "horns". Didn't want to go through all that. Your headers may fit differently than mine though.
Hello as you may have seen in my other post http://mmb.maverick.to/showthread.php?t=14841 i hit a water jacket in my other head and had trouble getting it welded up so i bought a new head it is now ported and polished as soon a i get the flow numbers from a flow bench i will post the inprovements. Jim
Here's a good tip if you want to remove the thermactor bump but you're worried about the hole in the roof of the port. Get a length of 1/4" steel dowel rod and drive it into the thermactor port from front to rear. Then you can remove the thermactor bump and have plenty of material. Also, the machine shop is right about the intake port.....to an extent. You can still port the intake runner by gasket matching it. I'd personally stick to raising the roof of the port and leave the walls and floor alone. Then, finish it off with 80 grit cartridge rolls. This will leave a decent texture to keep the air/fuel mixture from separating or 'wetting out' in the port.
i can understand porting.....but what does the polishing due to performance....how does it help? lets the air flow smoothly no turbulence??
Polishing really doesn't help in the runners. It just looks pretty to the 'uninitiated' and causes a lot of "oooohhhhs" and "aaaaahhhhs". Polishing the combustion chambers will help reduce hot spots that can cause detonation.
I am sorry shadowmaster but i have to disagree on the polishing part the smoother the ports are the better\faster the air will flow out the exh. I have my Exh ports and exh bowls ported and polished. Jim
Hmmm, my GT40Ps didn't have thermactor ports. Wonder if that's because I bought mine from Ford Racing instead of getting them off of an Exploder. BTW, I did polish my exhaust runners as an attempt to keep them from carboning up.
I am not for sure if thats what it is realy called but about an 1/2 an inch or so in the exh port there is a dimple about as big around as your pinky in the roof of the port. i just tryed to smooth it out with out cuting much or if any from it.
I've been told to polish the exhaust ports to keep carbon from building up as well. I've also been told polished intake runners costs performance. Any comments ShadowMaster?
The exhaust port is going to carbon up anyway. How much really depends on how well the mixture is burned in the cylinder. If the A/F is rich or the ignition isn't up to snuff....it's going to be bad. If everything is right and the stars all align.....you'll still get a light coating on the exhaust ports. Polished intake runners will lend themselves to helping the atomized fuel fall out of suspension and 'wet out' on the walls.
Jap901, the crater in the roof of the runner is a modified thermactor bump, serves the same purpose as in early Windsor heads. I opened up the roof of the runner from the top of the original port opening to the highest part of the crater (or would that be the lowest part of the crater? ). Removed a lot of material out of the roof. I've heard others mention about closing off the thermactor port, which runs the length of the head and connects all of the exhaust runners for the air pump. My heads don't have this port for some reason.
The exhaust port is going to carbon up anyway. Yeah, they still carbon up. What I found is they're easier to clean with less "tooth" for the carbon to hold on to. A bottle of fuel system cleaner in the tank and they look good again. "Polished intake runners will lend themselves to helping the atomized fuel fall out of suspension and 'wet out' on the walls." Exactly, you need just a small amount of turbulance in the intake to keep the fuel and air mixed. For the same reason you shouldn't smooth out the intake runners either.
