View single post by Esprit2
 Posted: 08-31-2020 05:41 pm
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Esprit2

 

Joined: 05-01-2005
Location: Minneapolis, Minnesota USA
Posts: 572
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discogodfather wrote:
Yeah it's probably just the very slim design of the pipercross 600, it was designed to go into very tight spaces. I don't think it has the volume necessary. It's wall is also too close to the ram horn aperture.Ahhh... you have airhorns inside the airbox? How long are they? Or more to the point, how close do they come to the opposite wall?

If you're running 45mm ID air horns, then 45mm is also the minimum required gap between the end of the air horn and the opposite wall. Sure, the air horn can be part of the overall 'tuned length' of the inlet runner. But in any airbox or enclosed air filter (even just a K&N chrome oval), you MUST have adequate clearance off the end of the air horn. In that case, you're better off running the shortest airhorn available just to get the smooth airflow lead-in provided by the shaped, curved inlet. You loose more due to encroachment than you gain with a longer airhorn.

If you have long airhorns that end up too close to the far wall of the airbox, then the small gap is choking off the inlet airflow. Try running without the air horns. If that improves the situation, then consider buying a set of short, stubby airhorns just to get the smooth entry.

My current daily driver is a Lotus Europa with K&N oval filters on Weber DCOEs. I'm running without airhorns because the long ones I have for it come too close to the far wall and restrict top end performance.

discogodfather wrote:
The airbox seems to, in general, kill the induction noise, so for now I can't live without the beautiful carb noise.Simple open air filters, like K&N or the Pipercross pretty much let all the noise out. An enclosed, 'hard' airbox does muffle the induction roar a bit, and a rubber coated Lotus airbox muffled it even more. But you can still hear it, just at a lower volume.

I've always used my Lotus cars as daily drivers, and there was a time when I was driving my Esprit S2 on a seven hour round trip every other weekend. The loud induction roar got to be a little tiring, and the reduced volume of the rubber coated Lotus airbox was more than welcome. That which is fun in small doses becomes a burden in extended exposure. Enough is enough.

I still like the sound. But I think I'd also like a volume control knob.

Regards,
Tim Engel

Last edited on 08-31-2020 07:58 pm by Esprit2