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Air Filter Assembly question

Scott_Hower said:
dons66 said:
Hap, in your first post on the subject, was your comment to not use a gasket between the carb and velocity stack? Any particular reason behind that?

Thanks

Don

I'm not Hap, but if I had to guess it would be that the gasket impedes/restricts airflow. I think you want this as smooth as possible downstream of the velocity stack radius which shapes the airflow.

(the gasket ID may be slightly smaller than the carb flange and the stack).

Yep, Scott nailed, no reason for it, it will do more harm than good. If i build a set of carb with this set up, I port match the v-stack to the carb throat to be dead nuts on, but the factory fit isn't that bad, but can be improved up easily during a rebuild. In the above pictures that carb has been port matched by me, as well as a few other performance tweaks.
 
Hap Waldrop said:
In the above pictures that carb has been port matched by me, as well as a few other performance tweaks.

I noticed the piston is chamfered at the bottom. Looks like it also matches the radius of the throat bore at WOT?

Do tell, what else was done?
 
On a follow up question to Hap. Something I didn't notice the first time I looked at his photo. What do you do about crankcase ventilation? No pcv valve that I could see in the photo.

Don
 
Scott, that carb set also has thinned throttle shafts.

Don I just run a small KN type filter on the front tappet cover tube, no pvc, kinda the same type idea as we do with the race cars, in short pressure does not to sucked out by vacuum, because well it's pressure, it just needs a path.
 
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