Change of Air Filters on my 4

[davidgsmith]

I am contemplating replacing my standard black pancake air filters as they have seen better days.

 

I have H6 SUs and am not sure whether to stick with originality and go "like-for-like" or to change to K & N or something similar.

 

Just want to get a feel what other people have done and if it's worth doing, regards change in performance, ease of cleaning, maintenance etc..

 

Thanks

[Ade-TR4]

I use K&Ns on my HS6s, they sound nice and, coupled with an extractor manifold, make a noticeable difference to the "breathing" of the engine.

 

http://www.tr-register.co.uk/forums/index....ost&id=1597

 

(previous posting/ thread)

 

Cheers

Adey

[davidgsmith]

Hi Adey, thanks for that.

Do you remember the part number of your filters and the dimensions of them? Are they offset?

They look good on your car by the way !!

David

[Trevor S]

Hi David,

I changed to K & N filters on my 4 from the standard black round ones. The rest of the "breathing" other than a 4a head is standard on my car so to be honest I can't say I noticed any real performance difference, although I don't really thrash my car anyway.

I have the round K & N filters which are 2" deep and 5 3/4" in diameter. Like you I have H6 SU carbs. At the time I bought the K & Ns they didn't make offset fittings and I had to buy ones with a blank backing and cut the offset holes myself which was a pain to be honest considering how much they cost. I think you'll find the none offset ones will foul the inner wing.

I think I still have the boxes for them in the loft somewhere so if you still need a part number let me know and I will try and dig them out. It may be that offset fittings have been produced since my experience of about 3 years ago, but I'd check first.

Regards

Trevor.

[davidgsmith]

Thanks Trevor, if you could get me a part number that would be great.

I have been to Moss top have a look today and the number they quote is KN 56-9132.

They looked about the right diameter but only about 1.5 inches thick, maybe thicker ones would be better still?

David

[Tr4Tony]

Hi

 

I also use the 1.5 inch deep K&N on SU HS6's as Adey does ...... very good.

 

You cant use thicker ones as they wont clear the inner wing ...... and the 1.5's are very close on the final oscillation before the engine stops in any case ...... if the filters are too close they smack on the inner wing .....!

 

Regards

 

Tony

[davidgsmith]

Hi Tony.

I don't suppose you know the cat. number of them do you? Would they be ok to use on H6s??

Thanks

David

[Trevor S]

David, I have checked my records. I originally attempted to get KN56-9132 which are for 1 3/4 SU with an offset fitting. At the time of my order in Dec 2003 K &N apparently no longer supplied the offset type and I ended up with KN56-9242 which had a blank fitting plate which I had to cut to fit myself. As I said before the situation may now have changed but provided you offset them the latter 2" ones fit fine with H6 carbs. I would be interested in how you get on as I'm considering K &Ns for my TR2 rebuild which will have HS6 carbs and clearance will be more of an issue.

Regards

Trevor.

[Ade-TR4]

As you can probably see from the picture, mine are the narrower type and are non-offset. (Obtained from Moss)

 

Tony's point about the final throw of the engine bringing the filters into contact with the inner wing is very true!

 

I've fitted the Pimpernelian engine-steady bar to the base of the engine and it has made a big difference to the engine movement. There is a bloke on ebay making them new (in the States I think).

 

Cheers

adey

 

(btw - Thanks David!)

[davidgsmith]

Just had some more information given to me,

 

56-9132 are offset but only 45mm. There is also 56-9130 which are 54mm offset (upwards) and 56-9096, which are also 54mm but straight, not offset.

 

Does this ring any bells with anyone? I think I would favour the straight type so they don't rub on the bonnet