Roy's got one.

Anyone dyno'd it back to back with a modded airbox?

I've run;
Open airbox, (i.e. no lid)
Modded lid (2*1.5" holes)
Open carbs.

Open carbs made 1-2 bhp more at peak but cost 3-4 bhp all the way up and past 10,000rpm.
Modded lid wasn't dyno'd but felt like it made even more mid than with an open airbox, wheather it cost even more at peak I don't know, it was a lot easier to get off the line to.

Whatever, modded lid would be my choice, I haven't got the skill, the practice time or the gearing options to setup on every track so finding myself way under 10,000 rpm with a 400 breathing down my neck is all to common an occurance.
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