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Discussion Starter · #1 ·
I was just wondering I have a set of Trick Flow twisted wedge heads for my 331 and was wondering if gasket matching help and is worth the money. Does it help to match the heads and gasket match to my victor jr. intake and exhaust? The machine shop said $250 to do this. Is this a good price? any performance gains?

thanks
 

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I have had port matching done at the exauhst header, lower intake to head and upper-to-lower junction. A port and polish is worthwhile if you want to ensure ABSOLUTE best performance from the combo. Muscle Mustangs & Fast Fords once did a comparison test and they picked up something like 5 or 6 hp on a normal aspirated combo and over 10 hp on a supercharged.
 

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For a street-driven car, it probably ISN'T worth it. You can do a bit of measuring & mocking up to see how mis-matched the various transitions are. I believe you would like to find that any difference involves air moving through a smaller opening into a slightly larger opening, so the flow doesn't bump into "curbs" as it passes down the tract. Others will probably chip in w/more technical explanations.

Best of luck,
Matt

Boston posted before I got in, & he makes a point which brings up another question. I have "read" that it is very important to keep the intake tract diameter as constant as is practically possible, to maintain steady velocity. If the runners are small deep inside the upper intake, grow at the matched mating points, only to shrink again as they descend into the lower, then open up to pass into the matched heads, where they constrict before getting into the cylinders, how much pulsation will this introduce to the airflow? Any porting pros here, or should this be carried over to "Ask the Experts?"
 

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Cobra0827 -

Do a quick check first. Using your intake manifold gasket, compare the openings in the manifold to the mating intake ports on the head. Use the manifold mounting bolt holes to locate the gasket. If the manifold intake port is smaller than the head port on all four sides and generally centered, the air flow will be OK. If that is not the case, the airflow will "hit" the side wall of the head port wall and you will have a tremendous amout of turbulence. In this case, port matching is worth it.

As said in the above post, port matching is very easy to do yourself. Using the gaskets you intend to install, mount them with the manifold bolts onto the manifold. Scribe around the port openings directly onto the machined manifold surface. Remove the gasket and grind the opening out to the scribed line. Blend the grinding work into the port about 1 inch following the general port shape. Do the same thing with the cylinder head ports. On street motors this is not a great power builder. If your ports don't line up well, it can make a difference.

Sorry for the long winded rambling . . . HTH

Ken
 

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Discussion Starter · #7 ·
Well I can do this with a dremel tool right? for the $250 they want to charge I can probably do this is a few hours with my dremel?
 

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It's pretty easy. An hour or two with a dremel and a carbide cutter and you're there. Probably not worth the time for an EFI engine. But certainly worth it for a carb. Big overhangs and underhangs can really cause problems.

I think the term "gasket matching" is a bit of a misnomer. You're not really matching to the gasket. The gasket may be as much as 1/8" bigger than the ports sizes. If you hog out the ports to match that, you create an hourglass shape. That will cuase a change in air flow speed as the it slows down and then speeds up again. No benifit and maybe a detriment for EFI. On a carbed engine, that will cause the fuel to come out of suspension and puddle on the runner floor.

What you're really doing is port matching. You want as close to perfect as possible to prevent variances in air flow. Here's how I do it. I'm sure there are better and more high tech ways to do it. But I only build street engines, and I'm really a cheap guy.

Place blue masking tape across the port of the manifold, one end to the other. Completly cover all the ports and all the bolt holes.

Now use a razor and trim away all the ports and bolt holes. Now you have an exact pattern for the intake manifold. Gently peel the tape off in one piece, and stick it carefully to a piece of poster board. Now cut out the poster board following the tape pattern.

Now you have a perfect pattern of your intake manifold. Place the pattern over the heads so the bolts holes match. You can see exactly where the intake ports will match up.

You'll have to trim a little off the heads and a little off the intake to get a good match. Take your time, go slow, don't overheat the bit. A little WD-40 helps. Blend the cuts in gently. All curves should be gradual, no sharp bends. Try not to make huge cuts which will dramatically alter the port size. It's really very easy.

Oh, and wear ear plugs.
 

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On the exhaust side - definitely forget about it for a street car with TF heads. They will be fine.

The TF heads as I recall, are almost a perfect match to a Felpro 1250 on the intake side. You couldn't do much to improve the port match.

The Vic Jr intake is also very close out of the box to the 1250, if just a bit smaller, which is what you want.

I would mock up a gasket and check it yourself, then decide. Bolt the heads to the short block and then mock up the intake with gaskets a second time, look down into the middle runners with a flashlight and see if the matchup is good.

I'm going to say it should be fine as-is and you can put that 250 toward something much more worthwhile.
 

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When I had my Edelbrock heads extensively modified, I had them port-match the intake manifold at the same time. Was it worth it? I don't know. But I had it done nonetheless.

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