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Trumpet air filter problem

Posted: Wed Sep 21, 2016 8:55 pm
by Username
Air filter problem. I've got a John Eals X over manifold with thottle bodies and trumpets. They have all been balanced and set up on the dyno so I don't want to touch the trumpets but as you can see on photo there's precious little room to put anything. I'm told to avoid socks and am therefor looking for a magical solution. I know --- poor design but I'm here now -----HELP
[/img]Image

Posted: Wed Sep 21, 2016 10:23 pm
by stevieturbo
There is room...just not tight to the trumpet.

Build or fabricate a box which will then allow you to route to a suitable filter, or place the filter onto the box.

That will at least give you some plenum area between each trumpet and any filter.

Posted: Thu Sep 22, 2016 5:16 am
by Ian Anderson
Are you wanting to have filters? Or just something to stop larger grit/small children etc bein ingested?

Ian

Posted: Thu Sep 22, 2016 5:40 am
by Ian Anderson
Something like this
http://www.webcon.co.uk/shopexd.asp?id=15262

You will need the dome variety or you loose too much airflow

Ian

Posted: Thu Sep 22, 2016 8:26 am
by Username
Thank you gentlemen!------ you guys certainly keep long hours.
The car is purely track only and I suppose in truth i don't know what level of filtration is really needed. I like the box idea but would grit and children perhaps be all I need for track and I want to try and catch the last race this year. What's the minimum I need.
P.S. I've got light weight body mods ahead and will look to an "air compartment" in that

Posted: Thu Sep 22, 2016 10:11 am
by Eliot
Ian Anderson wrote:Something like this
http://www.webcon.co.uk/shopexd.asp?id=15262

You will need the dome variety or you loose too much airflow

Ian
I'm sure i've read somewhere that those mesh filters are actually quite restrictive.

Posted: Thu Sep 22, 2016 10:20 am
by stevieturbo
Yep, mesh does not flow and it does not filter. Surface area...it basically closes over the hole quite a bit, even worse when it';s so small and close to the trumpet itself.

Posted: Thu Sep 22, 2016 12:35 pm
by Darkspeed
Can't offer much in the way of an easy fix for the air filtration but I would consider separating the leads a little.

I would send the photo to ITG and ask them what they can offer.

Posted: Thu Sep 22, 2016 3:21 pm
by Eliot
Can you not extend them and copy what Mr Eales did himself:
Image

Posted: Thu Sep 22, 2016 4:19 pm
by sidecar
The radius of the bellmouth is critical to gas flow, those push in mesh filters will totally mess up this area of the bellmouths. AJMHO!

Posted: Thu Sep 22, 2016 4:55 pm
by Username
Hey, much obliged to all of you.
1. Airflow is paramount
2.I've emailed ITG
3. I did not get Mr Eales to build the engine so I've got a wee pang of conscience if I have to get him to sort it out
4. In the mean time Il speak to my engine builder about different trumpets, but I know that this was an issue on the dyno.
5 The leads have to be properly routed yet along with a myriad of other issues to sort
6. I suppose I'd be pushing my luck to run a couple of races as it is.????????

I was running a 4 chock Weber quite well before all this ---- maybe simpler's better
Thanks again people

Posted: Fri Sep 23, 2016 11:24 am
by Eliot
Username wrote: 6. I suppose I'd be pushing my luck to run a couple of races as it is.????????
If you had an "off" into the gravel or just the grass, the probability of sucking in a load of crap is quite high.

Posted: Fri Sep 23, 2016 7:34 pm
by Ian Anderson
sidecar wrote:The radius of the bellmouth is critical to gas flow, those push in mesh filters will totally mess up this area of the bellmouths. AJMHO!
Hi you also get some that clip on over the outside of the bel mouth.
But I cannot figure out where they are advertised.

Average mesh on these gives about 65% of the surface area as open. And as physics would have it a semi sphere Has double the same surface area of the end of the belmouth. Circle pi r squared, total sphere 4 pi r squared.

Back to back dyno tests with and without the tea strainers resulted in a total 3hp loss. Would you even feel this?

Or do as some GT40s and build a turkey pan, this would normally sit under Ida carbs and seal between the manifold and "bonnet" causing cool air to be drawn in from under the glass.

On cross over manifolds you may need to do 2 turkey pans around your injector set up and then box in a filter.

But why hide such a nice set up.

Oh and if you have had an off kitty litter etc did you ever find grit in the top of your engine or valley gasket?

Ian

Posted: Sat Sep 24, 2016 6:04 pm
by Username
Yes I've been known to spend a bit of time off track so I think that's a no no

Hey Ian, I think the tea strainers sound very promising and will try to get some gen on that but I'm struggling to get a "vision" of the turkey pan thing which sound like the solution. Sorry if I'm being a thickco but I presume we talking about a sort of plenum or air box fed from a scoop or NCAA duct. A bit more info on that would be Grrrrreeeeaaaatt. ( or on anything else pertinent)
Finally, No, I don't recall picking any out of there but then I'm old and half blind they tell me so what do I know?
Thanks guys

Posted: Sun Sep 25, 2016 1:21 am
by unstable load
I think what he means with "turkey pan" is to fabricate a sheet metal "pan" under the carbs, extending outwards to allow you space to enclose the area, creating a plenum that you can then adequately filter.

Kind of like this MG, I would imagine...
http://www.britishv8.org/MG/LesGonda.htm