port detail on the FE intake adaptor

[427Fastback]

Question....do I need to blend out the CNC lines in the adaptor ??.I am not planning on any port work as they suit(size wise) the parts I am using...Engine is a edelbrock head 427 with a 270S cam..
I am thinking the lines run the wrong way but I am not a fuel distribution/intake port expert...Its easier just to ask...Cory

[Joe-JDC]

Does not hurt airflow.  Many folks run their CNC heads and intakes with the CNC marks as machined, and some even think it helps.  Sort of like a blc air flow(boundary layer air control) on aircraft wings.  Anyway, I have blended many CNC heads, and left some, and they seem to work well either way.  Joe-JDC.

[427Fastback]

Thank you sir....I know that making them too smooth is bad so I think I will just leave them as is.....Cory

[jayb]

My advice would be to smooth the machining marks out.  The ports are a hair on the small side anyway, to allow for some port matching.  Using a coarse cartridge roll to open them up to match the ports in the heads and the intake manifold will help airflow, and still leave the walls rough to discourage fuel from sticking there.

[427Fastback]

I believe the adaptor port is slightly larger than the edelbrock head port so the head would get opened up a tad.On the manifold side the adaptor would need some work to match the torker port but your dyno work has me thinking the performer would be a better choice and it has smaller ports...Options are good and I do have the tools here to deal with it..I need to get some gaskets and choose the manifold...I appreciate the input.......Cory

[jayb]

That's interesting, on my Edelbrock head ports the adapter port is a shade smaller.  Go figure...

[427Fastback]

I rechecked things today and the adaptor ports to edelbrock head is very close..The torker to adaptor is not as close as I thought and the adaptor requires more of a oval port to match the full size 4V port...Probably very minor work with the smaller port Performer...I will do more checking later...Finally got the glass installed in my 67 T/A replica so I am back focused on that project.....Cory

[Joe-JDC]

Depending on which intake you use, I would suggest blending any leading edge into the adapter/into the head that sticks out into the airstream, but the ridges won't hurt performance.  If you have the cartridge rolls and ability, then fine, it will work well.  Joe-JDC