Are you saying 240-250cfm? I was told the only way a cobra intake can match the improved design and flow of the trickflow or edelebrock RPM 2 or Holley even, is to be hand ported, and either cut in half and ported or extrude hone, a combination of both being the best though. Also you can decrease the runner length when you cut in half take out like an inch or so of the middle. That is what I was told, says in summit the intake is good for 400 hp, how much are you making?
Yes, 240-250cfm. The lower runners narrow down considerably on the approach to the head flange and are the restriction in the Cobra style intakes. I haven't seen flow numbers on the RPM2 yet so I can't comment about their flow. I don't know what bearing what I'm making has on this topic, but it's in the sig - base run with no tuning yet and it's not ported to flow 240-250cfm as the P heads can't use that level of flow.
I was asking 9150ho how much hp he was making to guage how much a stock cobra might be restricting, in my opinion if you are way over the 400 hp mark it is time to upgrade to the better intakes, besides the newest big 3 (holley edelbrock and trickflow) intake designs supposedly correct the far cylinder lean out common with the cobra and stock intake. I think the cobra is strong up to 400 hp though, they make good torque for the street.
Extrude Hone can net ya an extra 15 HP or so on a stock intake... other then that im not sure about the cobra,,, but the cobra > GT40 because the GT40 cant be ported
I know of a couple guys who run in the high 9's with their ported cobra intakes. the cobra intake is simply a cast version of the gt-40, and out of the box cannot flow quite as much as the gt-40 BUT because the cobra intake is cast, it can be heavily ported. I'm running a stock cobra intake right now.