K&N Air Filters

[John Harris]

Pete

In the opening paragraph I did say coming down the rev range.

From maximum advance down.

And yes is does complicate matters, that's why a conventional dizzy is designed with an operating envelope because most of the time it will not be timed properly, and so is designed to work OK, but not optimally unless properly times. 

And I did not seek to replicate the WSM, just to point out that a standard dizzy, whilst OK, can be made to run better, but needs some skills to do it, the same skills needed for a programable ignition. 

[dougbgt6]

My engine will be 50 years old next year, I doubt there's much on it that's optimum.  Thinking about it, who on here does have optimally tuned engines? JohnD, Clive, one or two others, maybe JohnH? I set my timing by ear, drive it, adjust it, repeat. Electronic ignition means I don't have to mess around with the points and spend more time driving. People put K&N air filters on because they're shiny and then spend hours trying to find why it's not running so well. My advice is spend less time installing bling or searching for optimum and spend more time driving and enjoying. 

Doug

[Clive]

3 hours ago, dougbgt6 said:

My engine will be 50 years old next year, I doubt there's much on it that's optimum.  Thinking about it, who on here does have optimally tuned engines? JohnD, Clive, one or two others, maybe JohnH? I set my timing by ear, drive it, adjust it, repeat. Electronic ignition means I don't have to mess around with the points and spend more time driving. People put K&N air filters on because they're shiny and then spend hours trying to find why it's not running so well. My advice is spend less time installing bling or searching for optimum and spend more time driving and enjoying. 

Doug

Not sure my spitfire engine is optimally tuned, I keep tweaking it...

But you are spot on about not fiddling. IF anybody wants to modify their engine, they really need to know all the implications first. An the fact many things are just a royal PITA (eg swapping air filters, the case here). Believe it or not, I reckon keeping a Triumph engine standard, or using standard parts, is a good idea. (ie if you want a hotter cam, use the cam/head/distributer off the best engine in the range) so it is all factory stuff. Electronic ignition is good, and admittedly programmable is better IF done well.

It is just like adjustable shocks. A dreadful idea for the vast majority of people. Then again, teh cheap black shocks are not great (though seem better than what they used to be about 10 years ago)

[foshi]

my 12/50 has k&N runs fine , came fitted with them though when i purchased it .

[AndyTV8]

My TR had a pair of K&N’s when I originally purchased it. I have no idea how old they were but I did renew them because they had ‘shrunk’ - it does happen after a considerable time. I replaced with a pair of cone K&N’s and have been happy with them.

I could improve matters in a couple of ways - add an air box with cold-air feed and also add a pair of stub stacks inside the filters. The offset filters I have don’t have enough room inside to accept the ones I’d like (MED Engineering) so that will have to wait, maybe one day. The Pipercross PX600 could be an option for the air box, but to be honest I’d like to see one fitted to decide if it would look out of place in my engine bay  

Mine also runs a 123Ignition Tune+  , it was very straightforward to set up after about 30mins to do the calculations to set up the initial curve, then just a couple of tweaks in use. I haven’t had to touch it since and it runs beautifully, I like the fact that if I ever get around to doing a rolling-road session then the advance curve can be refined further in about 2 mins rather than faffing around with different weights etc.

I completely agree that chopping/changing things without assessing each one can sometimes be like shooting yourself in the foot, but sometimes we have to fail in order to learn - it would be boring if everything was simple  

………Andy