Airfilter?

[Guest pwlcarz]

Hi all, not sure where this topic should be posted but thought I'd try here.

 

I had a rolling road session booked on Friday after junking the old chrome pancake airfilter and buying a nice Pipercross one from an autojumble. I wanted a short one to go under the bonnet and this fits perfectly.

 

However..... when the guy at the rolling road took off the bonnet and released the airfilter he said it was no good going ahead as the supporting metal cage inside the foam filter goes right over the top of the carb butterflies (it's a 32/36 DGAV on a 2L Pinto) and impedes the air flow.

 

In fact the cage almost touches the flaps when they are fully vertical.

 

He suggested I needed a taller filter but this won't go under the bonnet, or cut a hole in the bonnet to accomodate the taller filter, or ditch the 32/36 and go for side drafts - either Weber or Dellorto's.

 

While side draft carbs would be nice I don't really want to spend several hundred on a car that's only used for a bit of fun (actually I can think of other things I'd rather spend several hundred quid on!), so looks like I will need to stick with the existing carb for now, however whilst I'm reasonably OK with cutting another hole in the bonnet I'm not sure how suitable it would be to have the airfilter sticking up in the airflow. What happens if you use the car in the rain? Can the engine digest rain water?

 

As a temporary measure I've cut some 20mm lengths of steel tube and raised the base plate of the pipercross so that the butterfly flaps can't touch the underside of the foam, but this brings the top of the filter into direct contact with the underside of the bonnet. Engine seems to run OK though as I guess air is pulled in from around the sides.

 

Could I just fit a grille in the bonnet to let air in to the Pipercross? Still leaves the concern about water ingress.

 

What have other people done to overcome this?

 

Thanks for any advice

[speedtripledan]

You can get an adaptor that bolts on top of the carbs which you then attach tube to and move the filter where ever you want it look for the carb shops on ebay think they have them.

[SSSLINE]

You can get an adaptor that bolts on top of the carbs which you then attach tube to and move the filter where ever you want it look for the carb shops on ebay think they have them.

 

'Weber Plenum' in the search engine on ebay or google should find this.......

[Guest pwlcarz]

Thanks for the response guys.

 

Looks like the remote plenum comes out at around £57, plus cost of ducting and an induction kit cone air filter (Alpha) at around £30.

 

However, I reckon I might be able to get fabricated a reasonable copy of the plenum in stainless for a lot less than £57, sell the Pipercross and "bobs my uncle charlie".

 

One final question, going back to my original post, I've seen cars with air Filters sticking up through the bonnet, and on many cars with Side Draft carbs the filter sticks out the side. I assume either solution must pull in moisture laden air and in some cases even droplets of water, so still don't know if this is OK.

 

Any more thoughts?

[Guest robin]

you could look at getting lower engine mount rubbers to lower your engine in the chassis and stop the filter touching the bonnet? would definitely need a shortened sump though!!!

burtons might be able to help there?

 

robin

[megadodo]

When I ran my old BMW on twin Weber DCOE 45s the car actually ran best when the air was cold and moist, it's to do with air density/temperature etc. Obviously pouring water into the carbs wont do much good but the foam of the filters will vapourise the water to a certain extent when the engine is running. If the filter sticks out of the top of the bonnet however there is a chance of ingress when the car is sitting stationary in the rain and that can't be good for the carb or the engine!

[Snapperpaul]

A solution

 

NW Hoodies page 2

[Guest pwlcarz]

Saw my mate last night and proposed the 'plenum'.

According to him it will be a "piece of cake", so will post pictures once done.

 

Cheers

[Guest Jonathan Tall]

Saw my mate last night and proposed the 'plenum'.

According to him it will be a "piece of cake", so will post pictures once done.

 

Cheers

 

Thats right up there with

"How hard can it be?"

[Guest MrT]

Thats right up there with

"How hard can it be?"

 

 

I've not any room under my bonnet and never bothered with a filter, never had any issues just clocking 13,000 mile slike this

 

Paul

[Longboarder]

the supporting metal cage inside the foam filter goes right over the top of the carb butterflies

Er, he means the choke flaps unless you have the carb mounted upside down and I don't think a DGAV carb would work upside down.

 

You don't need the choke flaps so just take them out if they bother him or you Car will start fine from cold with a couple of dabs on the pedal and you keep the filter you have.

 

Makes me wonder if I would trust him with my engine if he can't tell a choke flap from a butterfly.

 

Nigel

 

Might still work better with a bulge over the filter, opened at the front to let in some fresh cool air!

[Guest HOODS7]

Ive got 38 dgas with K&N up through bonnet with no probs, filter element can be regularly treated to cope with moisture. Ideally you dont want to be drawing in that hot air from around the engine.