Comp cam XE262 in a 340

[ir3333]

...it's all good, as SSSSnake says lots to learn.
Is there any value to blocking the heat cross over in the intake to keep the charge cool?
Makes sense at the strip but does the heat provide better fuel atomization for a DD?

 

[d1970]

seeing we drive most of these cars in the summer, the up side of blocking the crossover is the intake stays much cooler resulting in a denser cooler intake charge. It also provides some insurance against vapor lock in the summer. If you drive your car all year long and have cold weather, I would not block off the crossover as you will need it for the automatic choke and for better fuel atomization.

 

[Snake]

seeing we drive most of these cars in the summer, the up side of blocking the crossover is the intake stays much cooler resulting in a denser cooler intake charge. It also provides some insurance against vapor lock in the summer. If you drive you car all year long, I would not block off the crossover as you will need it for the automatic choke and for better fuel atomization.

I agreeeeeeeeeeeeeee.Dam cold climate.

 

[ir3333]

..for performance a well mixed vaporized charge should make more power at lower rpm where we do most of our driving on the street.
..For passing the big end at 6 or 7000 rpm running a bit rich with as much gas as possible wide open through the traps is better...the idea behind the air gap style?
Post #46 outlines the steps to guard against detonation and maybe blocking the x-over would benefit that?And this should allow a short duration cam to be used in a higher compression street build and make better lo end torque.

 

[rumblefish360]

...it's all good, as SSSSnake says lots to learn.
Is there any value to blocking the heat cross over in the intake to keep the charge cool?
Makes sense at the strip but does the heat provide better fuel atomization for a DD?

Yes. To both questions.
In the colder weather, the heat will help. Colder intakes have a harder time with fuel distribution & atomization. So a unblocked heat crossover in a all season, daily driver or even a street strip car is OK to do and have.

Blocking the heat crossover and anything else to keep the intake charge cool is a good thing at the strip or in any wide open throttle application. The more power you want to make the less the fuel has to be atomized. W.O.T. runs do not like the fine mist fuel charge. Open cruise, mileage seeking and emissions like the fine mist fuel charge.

 

[T-N-T]

Specs on the 10200703 are
268/276/110/.44/.513 and 226/234@050
In at 106,this will net an ICA of 60*, and drop your your Dcr to 7.8/155@sealevel, too low for me. But not too low for a hi-stall and bigger gears as already mentioned. But faster lobes are out there.

I don't think it will change his DCR if compared to the 702 cam which has a LSA of 112*. In at 108 it should net the same 60* ICA as the 703 IIRC. The XE262 is ground on a 110 LSA.