Theories on porting intake to heads=

[cv67]

What real life gains have you guys seen

-bolting an intake on a head with nothing done

-getting the same # per manifold runner as the intake, or more? Any losses?

Say for example the typical 350/383 st strip motor with a single plane?
Who has delved down this path and lost?

Have done it a lot on TPIT/Superram intakes where the gains were huge (30hp/48rwtq!) as they were restrictive, and slight gains on my Team G.

[turbo2256b]

That would depend on the flow of your heads. good flowing aftermarket heads the intake might need quit a bit of work and almost never after the work to the intake will it flow the same as the head. A good match for a ported cast intake when bolted to the head would drop the flow 20 CFM or often more.

[cv67]

So is the theory having a head that flows more than the head? Do you feel youd lose velocity or signal as a sacrifice?

[cgarb]

Guy local to me who I've been using his flowbench to work on some heads of mine, we were discussing flowing an intake connected to the heads... my holley 300-25 only dropped the flow on my 292 heads 20 couple cfm's and he said that was very good for a out of the box intake. We were talking about that and would it be worth working the heads more and not touching the intake, how that effects power ect. He said that Improving the heads still will net a power gain. He has worked on 2bbl restricted intake classes for dirt cars and the intake and carb is the choke point. Even still with the choke point being there, he has found power on the dyno by improving the heads. He says the head will pull harder on the intake and carb. I have found that to be true somewhat in my experience. I worked on some FE heads for a friend of mines Torino. Ported, larger valves, more cam, more compression...same intake. We netted a small gain maybe 2 tenths on track. Changed out the 427 dual plane intake with a victor single plane...intake swap was worth 3 tenths on the track.11.1-11.0's to 10.70-80's.

[turbo2256b]

viewtopic.php?f=31&t=45372

check the figures on this head i ported and flow numbers on the intake bolted to the head before and after porting the head. Intake was as cast.