exhaust crossover in intake

[Tommie]

okay...
since i'm at the heads and intake, here's another thing;

I want to block off the crossover ports from the exhaust chambers (either at the heads or at the intake)...
what should or can I use to do that ?

I don't want that intake preheating system and I'm probably going to block the ports at the intake, but I'm talking exhaustgasses here...what's the treatment and material I should considder here?

ow, at the arrow in the pic is the opening I'm talking about...(just in case)

[Mike P]

You can normally cut a thin piece of stainless (slightly larger than the port big enough for the gaskget to seal) and block tham that way.

That being said, personally I would NOT do it especially on a driver in cooler climates. Blocking the crossover tends to lead to slow warm up and associated drivability problems until the engine becomes fully warmed up.

[kapp714x4fe]

I have a merc 410 in my 71 pickup. I am currently running an edelbrock performer intake, mild cam, headers and 2 1/2" exh, edel 750 carb, and c8ae-h heads. I am wondering if I would notice any gains by moving to a edel perf RPM intake. I do live in a relatively cold environment, would the lack of exhaust cross over hurt me too badly after warm up.
thanks,
kapp

[techinspector1]

Read these descriptions from Edelbrock and make up your own mind where you want the power.....

Performer® Manifolds (idle to 5500 rpm)
Performer manifolds are dual-plane, low-rise intake manifolds with a 180° firing order and patented runner design that you won't find in other brands. This patented design greatly improves torque over a wide rpm range for excellent throttle response, especially off-idle through the mid-range. Throttle Performers are ideal for passenger cars, trucks, 4x4s, tow vehicles and RVs. There are EGR and non-EGR versions available for most domestic V8 and some V6 engines. Most Performer intakes are 50-state street legal, when used with the correct carburetor and in the correct application. Check the individual listings for detailed information.

Performer RPM™ Manifolds (1500 to 6500 rpm)
Performer RPMs are dual-plane, high-rise intakes with 180° firing order to produce incredible top-end horsepower while retaining good throttle response. Their larger plenums and runners match the free-flowing exhaust, high-lift cams and other modifications of a high output engine. They are intended for high-performance street or competition engines that run up to 6500 rpm. They are not for emissions equipped engines. Edelbrock's Performer RPM gives you the ultimate in street high-performance.

Remember this, what you gain on the top, you give up on the bottom. There's no free lunch!