240 vs 260 intake manifold

[mayitin]

My question wich one is better? For years I was under the impression that the 260 intake was bigger and better that it would give you better performance. But now I was told there is not difference. To be honest I put them next to each other and it did not looked bigger. Can you guys educate me on this please. Thank you:stupid:

[70 Cam Guy]

I have both an N33 and N36. The internal diameters measured essentially the same with my calipers but the internal webbing is shaped differently. I could reach inside the ports and feel that the newer intake webs were shorter and more rounded. The N33 webs felt taller and sharper. I'm sure it contributes to air/fuel velocity and turbulence in some way... but I don't know how exactly.

As far as which is better, it's impossible for me to give you a conclusive answer. I switched from my N33 equipped '73 for the N36 when I did my header. At the same time, I removed the coolant lines from the intake, and used a non-egr balance tube.

All those things combined meant the engine revs much faster and more freely than before. There's a lot of discussion about peak power gains but I know my throttle response is better and the butt dyno tells me I gained something somewhere.

[mayitin]

Thanks Andy. let me asked you did you has a header before? I did the same as you but I put the N36 and Hmmm just do not know for me is hard to tell but at speed seems better but maybe is just me. I wonder if any body has try it on a Dyno. I may go back to the N33 and see if there is a difference. Thankx .:tapemouth

[70 Cam Guy]

I also did my header and N36 at the same time. I suppose the right thing to do to test would be a dyno comparison with only the intakes changed. I would have liked to do that but that's a lot of time that I don't have. What would really mess us up is if the benefits are more in the intangibles like drivability or throttle response :stupid:

I'm sure we've read the same old threads about this debate. It was pure coincidence that my round top SU's came mounted to an N36 intake. I cleaned it all up off the car. I pulled off all the original parts, stuffed them in a box, and installed the clean intake.

[Mr Camouflage]

I guess if anyone had access to an air flow bench, they could see which one flows better. If one flowed better than the other, then it's probably the better one to use.