What Air Filter Adapter - And Why?

The first one is an ARC High flow adapter part #6934. The third one is one is an addapter we sell from the Box Stock Project part #6926. Both are found on our website ARCRACING.COM. I shouldn't have to say which one I am running or why...LOL
Just wondering if any of them are made for a specific "sweet spot". One better for high end, one better for low end, etc
HM adapter is a piece...from a BSP one to this is a slight increase in throttle response, and a slight increase in the top end...along the same lines as the ARC, and Airspeed...
We've been running this AF adapter, with good luck.


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I use the black airspeed adapter, but it gets to be a real pain taking it on and off, which usually takes at least 5-10 mins to do because of how the nuts are
I used to run the one like older n dirt show but I switch to the airspeed. Won race with both only reason I switch to airspeed is pmi is only 30 min from me. Yes there is a trick to getting the nuts on the airspeed but after you done a couple take less then a minute nuts are started. Kinda like everything else a racer like a certain part they stick with it not better or not worse just a part that the racer like.
Maybe Barry (youngengines) could chime in. I think he has about everyone made by now. What i know of him, he is always itching to do a dyno comparison. He need very little reason to do one, I assure you. I just bet he has compared them on the dyno. Heck i bet he has compared paint color of the tins on the dyno. I would think very little difference as long as a smooth transition is made where it meets the carb.
New to the rules: Can the inside of the adapter be polished smooth, or do you have to leave the original finish, machining marks?
If you have one of the ARC 6934 high flow adapters polishing the ribs will hinder flow. They are there for a reason. As the air come through the filter it is very turbulent and the ribs help direct the air and begin it swirling into the carb.
Different builders doing different things will see different results with the flow. One builder we've ran engines from uses the filter adaptor like older than dirt has shown and likes the results of that on the dyno. Another guy we've got an engine from tested the same filter adaptor on one of his engines and it didn't perform as well as an airspeed. So. Its all dependant I guess on what they each do.


WV Race Fan
JGRfan I have this one for sale along with 3 others. sending you a PM

6934 ARC Clone/GX200 High Flow Air Filter Adapter