Do you use air filters on your side draughts?

[Rich T]

I know what air filters are for, its obvious.

But do you use them?

I dont at the moment but the car is coming off the road for winter soon so considering weather to for next year and onwards.

Personally im not to worried weather or not it does/doesnt look better with them.

My only concern is a spit back from the carbs and the filters setting fire.

What do you do??

[preacherman]

It's scary when it does happen.this was due to a cracked petrol pipe near the dizzy. The ramair filter certainly accelerated the fire . Took ages to get the carb clean.

[colr6]

I’ve always used K&N filters as against the likes of ITG foam style filters exactly for that reason. Not that I’ve had one go up in smoke yet but understand your concerns. If the carbs are suffering with that much stand off or spitting back maybe a further look into set up is required.

[Rally Pack 2000]

2 hours ago, colr6 said:

I’ve always used K&N filters as against the likes of ITG foam style filters exactly for that reason. Not that I’ve had one go up in smoke yet but understand your concerns. If the carbs are suffering with that much stand off or spitting back maybe a further look into set up is required.

K&N here for me too. Used them since the 80s when David Vizard recommended them in his book as I had never heard of them before. I had a set in the Twincam since I bought it and it does suffer quite dramatically from spitback at times and while the elements never caught fire the polymer rings that form the top and bottom rings of the filer did shrink with time so that the filters lost half inch in length. Even though perfectly usable it look a bit crappy. I contacted K&N after 20 years in the USA to ask about it and they mention that heat resistant plastics weren't as evolved then and their older filters did in fact shrink sometimes. They had some kind of lifetime warranty on them or something so they posted out new elements happily. After 20 years of use you cant ask for better service than that. I then had the housings re-chromed to make them look all new again.  I put wing nuts on mine so I could drive it to events with the K&Ns on and whip them off to put the muffler style original air-filter on when I had to show under the bonnet.

For the Mk2, in its Pinto downdraft, I used a small oval for a while but the concave bonnet of regular Mk2s means you couldn't fit anything but a really thin filter on it. Add to that the high lip of the 32/36, there was  barely 10mm clearance between the top of the filter and the top of the carburettor and the movement of air round that tight bend made it sound like a vacuum cleaner. At the time K&N didn't make huge round elements for the early style original Pinto air-filter but they did make a flat type one for the later European Mk2 RS2000 type one. I also like how it was designed in that this air-filter housing ramps up the flow to the top of the carburettor rather than simply sticking through it forcing the air to take a sharp bend up and over. Its flat shape filter element  also makes it easier to clean.

What I like about K&Ns over the sponge type too is that the elements are thin and pleated.  You have to use their own cleaner and oil but it works very well. You can see them getting clean unlike the sponge type which I could never get the smaller particles from deep within the sponge. Mind you that technology has probably advanced by now but I have never had the need to change back from K&N.

[Rich T]

Thanks for your input chaps.

I'll have a think about it over winter. Looks like k&n are the way to go if i put filters on. 

Ive seen the mesh trumpet covers so may think about getting them. Well, they'll keep the birds out 😁.

Tbh i wasn't that impressed with the tuners. Theres a  bit of a flat spot at about half pedal. Should have rung them straight away but dont really want to go back to them.

It only splutters occasionally but thats enough so I'll avoid the foam filters.

Rich 

[npikey]

I have naked trumpets   I’ve tried k&ns and the little mesh filters and suffered with flat spots, I was advised to try with out any and it’s smoother and doesn’t spit back any more, I don’t do millions of miles but haven’t had any for about 8,000 mile with no birds or straw getting sucked in  

 

[hooligan]

I too run naked trumpets without issues, what main jets and air jets are you running Rich ?

shouldn't really be spitting back through the carbs if it's running correctly, I do keep a small fire extinguisher near me in the car just in case, make sure it's not a powder extinguiser as they can do more damage to your engine bay than the fire itself. 

 

Super Help SH2400 Fire Stop Small Fire Extinguisher

 

 

[hooligan]

I recommend one of these close to hand 

[Vista]

47 minutes ago, hooligan said:

I recommend one of these close to hand 

Firestop SH2400? That's a 400ml extinguisher, it doesn't even state what the extinguishing medium is. I'm sure it's fine for small (and I do mean small) electrical domestic or caravan kitchen type fires but if you have a fire involving petrol or oil under your bonnet, then you may as well piss on it as use one of these. Opening the bonnet to use this in the first place risks exposing you to a fireball from the sudden influx of air as the bonnet lifts. Read the reviews of it on Amazon (or similar) and they're all largely positive, but how many of those reviewers have actually had to use it in anger? I'll wager extremely few.

A larger powder or foam extinguisher is much better for under bonnet fires and providing the engine isn't running at the time, and you wash it off promptly after the fire's out, the powder won't do any damage.

Look how long it takes to extinguish a small piece of cardboard in a conveniently sited tray

 

 

 

[katana]

Totally agree on those 'air-arsole' extinguishers! A 1kg CO2 hand held as a minimum is better than nothing but for under bonnet, i'd go foam anytime - crack bonnet and send it!

[Rally Pack 2000]

Many years ago our Escorts had a problem with people reusing the original single use fuel hose clips at the carburettor. A friend lost his Mk2 Ghia through just such a fuel fire. Its difficult to find a discrete place to keep an extinguisher of any measurable size. I just keep one of these. Yes its only 500 grams but its powder and is suitable for oil, fuel and diesel. Even more odd its made locally. Its better than nothing but volume limited so you have to get the job done before it gets too out of control.

       

[Rally Pack 2000]

To the original issue though some getting flat spots with filters especially with K&Ns this isnt a fault with the filter medium itself but the shape and size of the filter your fitting. Narrow filters on down-drafts and tight flow entry into carburettors can cause flat spots and similar issues with narrow filters and incorrect length or no trumpets can case the similar issues on side-drafts. You can count your fortune that a consistent wet weather keeps your dust particulate levels reasonably low that you have gotten away with lack of filters but you are playing Russian Roulette. We had a mild dust storm sweep through Sydney last night and only evidence of it was dew on cars had turned to mud spots on the paint. You would have only gotten half a mile down the road without filters before doing some kind of damage. Seek some professional carburettor tuning if needs be but air filters are not whimsy that car manufacturers use to decrease power they are important protections. I cringe here sometimes when I hear some of the amazing high-spec engines built by people here on the forum and then they dont run filters. Even with filters I have to clean out mud sludge in the fuel bowl of my Webers, while admittedly its dryer and dustier here but all the cars around you still kick up the dirt and dust around you there even if it rains alot.

[katana]

I did extinguisher use training a while ago and the guy was pretty emphatic powder or CO2 was pretty much for any 'dry' fire ie. paper, wood etc and electrical. Any fats, oils or liquid fuels then the foam is the go to, as it smothers by covering the fuel and preventing ignition. He did admit that dry powder could be used on liquid but it takes 'shed loads' of powder as it must exclude air to work (which would be difficult through a barely cracked bonnet!)

[Vista]

4 minutes ago, katana said:

I did extinguisher use training a while ago and the guy was pretty emphatic powder or CO2 was pretty much for any 'dry' fire ie. paper, wood etc and electrical. Any fats, oils or liquid fuels then the foam is the go to, as it smothers by covering the fuel and preventing ignition. He did admit that dry powder could be used on liquid but it takes 'shed loads' of powder as it must exclude air to work (which would be difficult through a barely cracked bonnet!)

Correct, foam is the best fire suppression medium for oil / fuel based fires as it smothers and cools..................but Powder is a close second if that's all you have and it's knock back effect if directed through a popped bonnet is quite good.