K&N air cleaners

[rootesrob]

My Series V is basically stock (Strombergs) with the exception of a Lucas sports coil and hotter plugs - running points in dizzy at the moment. The car runs great with the stock air filters, but thought I'd try some K&N's.

Well, the car did seem a little faster on acceleration, but the engine did not run as smoothly; needed lots of choke (wouldn't warm up as much); the valves sounded clackier than usual; the engine shut off a bit rough.

Lowered the jets to enrich the mixture, but didn't help. What's going on?

Also, noticed that the air port cutouts on K&N backing plate had two little holes instead of the standard rectangular cutouts. Does it matter?

Would Pertronix ignitor help? Thanks.

 

[64beam]

Hi,

I asked a similar question in a different post a little while ago. I was told the K&N normally would'nt require any jetting changes in the carburettor. In saying that, I have read that when changing to a K&N may require small jetting changes. So you may require a jetting change. Hopefully someone who has the same modification will answer you post as well. The base plate you have may suit a few types of strombergs thus the various holes (just a thought).
The pertronix ignitor are a good investment, but I'm not sure that will cure the problem.

Hope I have helped a little,

Regards, Robin.

 

[rootesrob]

Thanks Robin for your reply.

The thing about setting the jets on the carbs is they're set (balanced, low speed idle, etc.) without any air cleaners on in the first place. At least that's how I interpreted the WSM. Was wondering if anyone could go through the mechanics of how the engine acts like a pump, draws more air into the mixture with the K&N's, etc., etc...
Why would the valves sound chattier??