2bbl heads

[turtle1hp]

well.... ummm.... you see what happened was.... the dog ate my dyno sheets.... Stop laughing. It's not funny... It's true!! LOL Guys. I have enjoyed the conversation and the abuse, but I gotta go. I hope everyone has a Happy Thanksgiving!

[ford396]

Actually that is not that large of a head. Very long runner allows for more cfm in the runner. Cross section still small enough to promote excellent velocity under the two barrel carb.

Actually it was a gm engine.

I also tap out. Enjoy your conversation stock car.

[fastford]

these conversations are about the only reason I come to 4m any more , you would be amazed how much an old dog like me can still learn on here, sure we call BS sometimes, and sometimes were right and some times were proved wrong, that's how you gain knowledge if you want it, any way happy thanks giving all.

[Lizardracing]

You can only pull so much air through a 2V carb so how would increasing the runner size help?
I can't imagine a bigger pipe moving the same amount of water any faster....

Compression plays a big role in the power produced when the supply of of air is less dense.

[let-r-eat]

The 2bbl is rated at 3" HG flowing 500cfm. What happens when you pull 9 or 10"?

Pulling vacuum at WOT under a 2bbl carb is where it's at. You can do that with a big port or a small one.

A port must maintain proper shape for the valve size. Running a 2.15 valve is going to require a certain CSA/CC the same as a 2.02 is going to require a certain CSA and shape. The intake runner is just an extension of this.

The vortec bowties run so well because of the efficient chamber. Couple that with the right other stuff and you're good to go.

[Lizardracing]

ummmm what?

[powerslide]

ummmm what?

he clearly said....via Imgflip Meme Maker

[let-r-eat]

11-27-2015, 05:19 PM #32 Lizardracing Lizardracing is offline
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ummmm what?

A port has a nice shape when a consistent and proper velocity profile is achieved throughout. That will require a smaller port on a 2.02 than for a 2.15 valve. A 2bbl engines needs a lot of vacuum under the carb at wide open throttle to make power. The more vacuum under the carb at WOT the more air that's going through the carb and the more power you are going to make. How do we create this? We create this with the proper cam, eliminating dead spots in the induction, the proper exhuast size/shape/length etc. etc. etc.