2.2 Port Size & Valve Brands

[Neven911]

Hi Everyone,

I'm getting down to the details of my rebuild 66/85, 9.5CR, 40 Webers, 2.4 Heads and Mod-Solex or Mod-S cams, this is primarily a street engine. I have a couple of questions...

1. Should i look at increasing the port size of the head, I've read here and elsewhere that this makes a difference

2. Any particular brand of valve i should use or avoid?

Thanks Neven

[Richey]

If they are not S heads , absolutely . You do not want the engine to sign off at 5,000 RPM . Make the ports S dimensions : 36 mm intakes and 35 mm exhaust .

[Neven911]

Thanks Richey

[Henry Schmidt]

Port size is important. Engine builds require a symbioses between parts selected and flow characteristics.
After 60 years of development there is very little mystery left.
Higher horse power requires more RPM which in turn requires more flow.
Match the ports to the cams, match the cams to compression and the compression to intended purpose.

As for valves, we see a lot of inconsistency in the aftermarket valves available today.
Stem roughness, stem diameter and head concentricity and Rockwell.
The valves we see with the most consistent quality control are SI's Silver Line stainless steel valves. They feature undercut stems for improved flow, swirl polishing, chrome stems and stellite tips at a reasonable price.

[Neven911]

Thanks Henry
That's the approach we are taking, head flow first. One question have you ever used or considered using 8mm stem valves on a 2.2?
Thanks Neven