On 17/05/2021 at 15:15, Thefeliciahacker said:

air will exit out just because the underside of the car is a low pressure zone and the inside of the engine bay is a high pressure zone.

 

I wonder, a ''low-profile'' hood scoop like this

 

 

 

can create problems to the radiator of the a/c? Can soak air thought this?

As you know beneath that scoop is the factory grille and the metal lip that drives outside air to the cabin filter and i am trying to find a way to cover that grille so water from rain or car washing won't get inside that filter.

i think you are trying to improve a design that honestly works

1 hour ago, Thefeliciahacker said:

i think you are trying to improve a design that honestly works

 

I copy that idea from Autobianchi

 

 

which had a scoop on the hood and a much more wider space for ''cabin filter''.

 

21 hours ago, D.FYLAKTOS said:

 

I copy that idea from Autobianchi

 

 

which had a scoop on the hood and a much more wider space for ''cabin filter''.

 

And much more room in the engine bay 

1 hour ago, Thefeliciahacker said:

And much more room in the engine bay 

 

My problem isn't the space, i have plenty of it. The fresh air from the hood does not reach the top of the sponge (''cabin filter'') and has a gap which is filled with bad smells from the engine bay.

The system is not sealed and dirty air comes into the cabin.

17 hours ago, D.FYLAKTOS said:

The fresh air from the hood does not reach the top of the sponge (''cabin filter'') and has a gap which is filled with bad smells from the engine bay.

The system is not sealed and dirty air comes into the cabin.

(I've not read the thread so this may have already been covered.)  In that case could you not just extended the sealing with a tube, plate, compressible trunking or extended or another seal, something to fill the gap and seal the passage of incoming air from above the bonnet?

 

1 hour ago, nta16 said:

 In that case could you not just extended the sealing with a tube, plate, compressible trunking or extended or another seal, something to fill the gap and seal the passage of incoming air from above the bonnet?

 

I need the incoming air from the hood, otherwise how the blower (heat and a/c) will work?

The problem is that with the environment air, water (rain-car wash) plus some other things coming inside (bugs, leaves, tree branches etc) and landing on the sponge and the existing mesh of the grill is not enough.

The idea behind a small scoop is that will provide some sort of extra protection from rain-car wash plus air debris.

 

Not something fancy as the WRX or 60's muscle car had but something like these examples:

 

 

On the other hand i don't know if the curb of the scoop will not let the blower to ''soak'' air as it should be and force him to ''push itself''.

 

 

 

With a scoop perhaps you can use something less restrictive than the present foam.  My total guess would be that the scoop would give you a greater volume of air coming in so you could keep the foam filter but that's just a guess you would have to do mock up tests at various speeds and in various circumstances with a some kind of measuring instrument to know for sure.

 

Getting hot air out of the engine bay is the more difficult process rather than getting air in.

 

I do not understand your worry of the blower motor as you presumably have a recirculation setting that cuts off the air from outside anyway and the blower motor works with that.

 

3 hours ago, nta16 said:

so you could keep the foam filter

 

I do not understand your worry of the blower motor as you presumably have a recirculation setting that cuts off the air from outside anyway and the blower motor works with that.

 

My cabin filter is a charcoal sponge ,every time is raining or i go to a car wash it's gets wet. That's among other problems that i had with it.

The metallic lip that brings fresh air from the hood's grille has a gap of 3-4 cm and does not touch that sponge so from that gap odours from the engine bay ''hit'' all day that sponge and pass through it inside the cabin.

 

When i press the Recycle button i feel that the blower gets air from the cabin and push it outside through that filter and my concern is: with that scoop above would be capable to soak or push the air easily or this scoop will make things tougher?

I want to put a small scoop to protect the ''cabin filter'', it's not like Muscle Cars that wated air from the hood to ''hit'' their air filter or like Subaru WRX STI which want that air for their radiator.

15 minutes ago, D.FYLAKTOS said:

My cabin filter is a charcoal sponge ,every time is raining or i go to a car wash it's gets wet. That's among other problems that i had with it.

Yes that is why you want a scoop, I followed that, you want to give it an open hood.

 

16 minutes ago, D.FYLAKTOS said:

The metallic lip that brings fresh air from the hood's grille has a gap of 3-4 cm and does not touch that sponge so from that gap odours from the engine bay ''hit'' all day that sponge and pass through it inside the cabin.

Yes I understand that, you have two problems this one I thought would be solved by my answer 8 hours ago.  You should not have engine bay fumes coming into the cabin that is why seals and grommets are fitted to items passing through the firewall/scuttle.

 

19 minutes ago, D.FYLAKTOS said:

When i press the Recycle button i feel that the blower gets air from the cabin and push it outside through that filter

Then surely something is not working or fitted as it should be, the idea of recirculate is to prevent external air, in modern well sealed cars you should not leave recirculate on too long.

 

25 minutes ago, D.FYLAKTOS said:

I want to put a small scoop to protect the ''cabin filter'', it's not like Muscle Cars that wated air from the hood to ''hit'' their air filter or like Subaru WRX STI which want that air for their radiator.

Yes I understand this too but a scoop might (or might not depending on how it is done) bring in more air, a limiting factor might be the filter you use. and the size and type of mesh you use on the scoop, if you use any.

 

First thing is to seal the metallic lip to the filter housing as this will bring in more fresh air and seal out engine bay air and fumes.

 

13 hours ago, nta16 said:

 

First thing is to seal the metallic lip to the filter housing as this will bring in more fresh air and seal out engine bay air and fumes.

 

That's why i have made some thoughts here:

https://www.briskoda.net/forums/topic/491645-can-i-make-a-modification-to-my-felicia-13-filter-case/?do=findComment&comment=5759492

 

After the "sealing" procces it's time to think about the scoop mainly as cover (water, hairs etc).

On 02/06/2023 at 18:50, D.FYLAKTOS said:

My problem isn't the space, i have plenty of it. The fresh air from the hood does not reach the top of the sponge (''cabin filter'') and has a gap which is filled with bad smells from the engine bay.

The system is not sealed and dirty air comes into the cabin.

It is sealed with a door type seal

3 hours ago, Thefeliciahacker said:

It is sealed with a door type seal

 

I don't know how good it does it but the metallic lip not only does not touches the sponge (no marks on it) but does not touch even the metal mesh that i put to stop leaves-bugs etc.

As you can see the mesh is untouchable.

 

 

 

Which means if there is a space between the hood and the seal (of the cabin filter) then dirty air comes through inside the cabin.

1 hour ago, D.FYLAKTOS said:

don't know how good it does it but the metallic lip not only does not touches the sponge (no marks on it) but does not touch even the metal mesh that i put to stop leaves-bugs etc.

As you can see the mesh is untouchable.

 

The seal should be on the heater box and seals against the bonnet around the lip. 

It's not clear whether it's present on your car, from the photo you rovided.

 

I have post them in the past, here is mine:

 

 

 

 

 

 

 

I always wondering why the metallic lip (that brings the air inside) is much smaller that the size of the sponge.

 

 

 

If i make it wider wouldn't be good or this will change the pressure of the incoming air? The blower inside would be ''happy'' with more quantity of air?

 

25 minutes ago, D.FYLAKTOS said:

I always wondering why the metallic lip (that brings the air inside) is much smaller that the size of the sponge.

Yes I wonder that too - but, it is what it is so you have to work with what it is.  Surely you can make a seal that goes around the metallic lip and is wide enough (thick-walled) to also cover the whole of your filter and heaterbox intake, perhaps removing the existing door type rubber seal.  A (watertight) foam type has been suggested as this can be compressed, or also be cut to allow for any angle of the bonnet slope if required.

 

Edited 5 June, 20233 yr by nta16
ETA: watertight

33 minutes ago, nta16 said:

perhaps removing the existing door type rubber seal

 

One of my ideas is to remove that factory seal and go to a repair-shop to make for me an oval shape metal ''lip'' (wider that the original) to cover the plastic oval ''nest'' of the sponge filter, will go down few cm further.

Also to cut the original ''lip'' and make it bigger but if i make it wider wouldn't be good or this will change the pressure of the incoming air dramatically?

The blower inside would be ''happy'' with more quantity of air?

Yesterday i made a ''sealing'' test, i put a piece of cardboard standing upright and i closed the hood, here is what happened.

 

 

 

On 05/06/2023 at 09:05, Thefeliciahacker said:

It is sealed with a door type seal

 

It didn't went all the way down, a part of it protrudes upwards so i done another one test, i lay down the piece of cardboard

 

 

 

and i closed the hood, the result must be one: the rubber seal reaches the oval area of the hood

 

 

 

sealing everything and the cardboard must be crumpled up.

 

On 05/06/2023 at 14:21, Papez said:

The seal should be on the heater box and seals against the bonnet around the lip. 

 

 

Theoretically Yes but here is the result, the cardboard is untouched !

 

 

 

As i expected by instinct, there is a gap between the hood and the rubber seal (no crash accident, the hood is the original) and dirty air from the engine bay passes to the sponge filter and then inside the cabin.

I thought you had already checked this and knew there was a gap hence the suggestions of changing or further sealing.

 

2 hours ago, nta16 said:

I thought you had already checked this and knew there was a gap

 

 

I knew it by instinct, proved twice with simple evidence so other Felicia members can find relative informations via Google search if they have the same concern & problem.

4 hours ago, D.FYLAKTOS said:

As i expected by instinct, there is a gap between the hood and the rubber seal (no crash accident, the hood is the original) and dirty air from the engine bay passes to the sponge filter and then inside the cabin.

 

But you can se quite clearly that the seal was doing its job, as evidenced by its outline on the bonnet.

So either the heater box somehow shifted downwards or the seal got squished and you need a new seal. Or maybe pull it upwards a bit, if there's a space.

2 minutes ago, Papez said:

But you can se quite clearly that the seal was doing its job, as evidenced by its outline on the bonnet.

 

For sure, the marks show contact but the latest years things changed.

If i can i will lift the seal and make it more soft with products for this cause or apply a thin layer of rubber foam at the oval marks of the hood to make the contact with the seal more efficient.

I don't think that i can find a new seal.

 

You might find a seal with a better profile for your current installation, have a look at places that do seals, I'd have a quick look at "classic" car trim suppliers, car builders' suppliers sites, kit-car builders' sites, custom/modified suppliers sites, eBay seal suppliers, for whatever profile you think will suit your needs.

 

Surely it can only be that the bonnet is now higher, or the heater box lower or the seal has squished but as I put earlier it is what it is so if nothing else is wrong then a seal that fits the current situation should resolve the issue.

 

Hi Sirs, I was reading the complete tread.  First of all i don't find useful that bonnet scoop.  But in my case i made my own test with the inside grid of the cabin heater, putting the grid inside a piece of pantyhose.  Yes, a pantyhose.  Ask your Mom, Aunt, sister or a friend for an used one, This nylon elastic mesh acts quite well and depending on the stretching you can adjust that filtering net power. As a result it stopped all sizes of bugs, leaves and other types os debris. Driving in colombian streets and roads isn't  too clean.

 

Also, it is interesting to check the sealing between the inner bonnet intake and the blower box.  It comes to my mind the idea of placing a kind of rubber band or belt upright all the way round the blower box grid and approach to fill the gap where Fylaktos did the sealing test with cardboard.

12 hours ago, automobilova said:

This nylon elastic mesh acts quite well and depending on the stretching you can adjust that filtering net power.

 

Also, it is interesting to check the sealing between the inner bonnet intake and the blower box.  It comes to my mind the idea of placing a kind of rubber band or belt upright all the way round the blower box grid

 

Yes but how are you going to fix it around the oval shape of the pladtic box?

 

I have made a test with sticky rubber and failed, caused me problems as the hood was going down.

That pressed down the factory rubber beneath the plastic covers of rhe wipers.

 

I am on vacations, i will post photos when i return.