vee93: I purchased a new airbox lid at the same time, and the filter doesn't fit properly into either of them. And yet the stock filter (which does have the correct stock part number) fits both perfectly. So I don't think it was altered.
It sounds like a goodly number of people have had trouble getting it to fit. Some, like me, gave up on it.
I'll put it this way. If I was determined to make it fit, I would succeed in making it fit. But based on other postings about dyno numbers, I'm not convinced that the K&N makes an improvement on the Corvette application (it definatley does on other vehicles with smaller filters!). If someone posted that they dyno'ed their LT4 before and after K&N only and it showed a few more horses, I'd go out there and make my filter fit.
But what I've read shows different. The dyno showed the K&N adding nothing at all. The filter is just so big, that K&N, stock, and no filter have the same results. No restriction to flow whatsoever is coming from the filter.
So I don't feel compelled to go through the effort of making this filter fit. I still can't see any reason for it to not have been constructed to exactly the same size as the stock filter and just drop in without any special efforts or alterations.
I'm not willing to fight with it, jury rig it, or spend any effort altering it when there aren't any apparent gains to be had. As far as I can tell, it's a fairly useless product on the LT1/LT4 Corvette. And it's just floating on the name.
On other vehicles it's a definate boon. Don't get me wrong. It had a noticable effect on my K-5 Blazer. But I think the usefulness of K&N depends on the particular application.
- Skant