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Air box lid worth it?

3776 Views 5 Replies 4 Participants Last post by  Yoderwagon
Looking to get the ehs billet intake with a Uni filter (mostly to get rid of the crappy design by Yamaha), from what I’ve been reading the lid doesn’t do as much as it did on the previous models. I already have a programmer and barkers exhaust.

Anybody have both the intake and the lid that can chime in?
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Here's my review of the setup I installed little less than a year ago.


I do not have the modified lid and I explain my findings in the thread. I have since then also tried it again and even tried a trick I have done in the past on other machines where I would unclip the air box lid, lift it up, and then tuck a couple of the clips in the rear of the box and set the lid on them to vent it some. Even this resulted in less bottom end and throttle response with only a slight gain in the upper middle to top end. Not worth the trade off at all.

It's odd cause over the years removal of the air box lid or this little trick has helped some machines and hurt others, even with changing jetting (all my previous machines were carbed).

Id also like to add that while for hundreds and hundreds of miles after the intake install the machine always fired up and stayed running on the first jab of the start button, it since has occasionally done like the past where it would start and die and then the second jab it would be good to go. My buddies 14 model does this as well as another's 13 and a 12 model I knewof also would at times. Don't have an explanation but it's really never been an issue to me personally.
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Here is a post talking about similar observations that KYGrizzly is reporting. The original article and website by Hunterworks are gone now.

Hunterworks does dyno their research. But it appears to me that he is looking at the wrong sensor.

Since that the AP sensor is attached to the throttle body. It seems to only detect air pressure outside of the air box. My Opinion is that the AP sensor is not effected.
What is in the air box is the Air temperature sensor. Adding high velocity cool air across the AT sensor may confuse the ECU into thinking it is colder outside causing the ECU to enrich the mixture.

My 2.0162¢
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Both good reads. Thanks for the info and I think I will only get the flange and filter and skip on the lid
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