I'm interested in more information concerning the 'twin layer gauze filtering screen'. Is this screen more or less restrictive than the corrugated cotton gauze cylindrical filter?
If it is less restrictive, how good are it's filtering properties and what percentage of the air goes through the corrugated cotton gauze cylindrical filter vs the 'twin layer gauze filtering screen'? Thanks
I saw an early version of this filter on a local MCS and the end was 2 layers of foam, one coarse, one fine. The picture on GTT's web site still looks to be a foam end. I am not a fan of foam filters or I probably would have ordered one of these already and if by any chance it's changed to two layers of cotton gauze, well that's worse than the 4 layers of the rest of the filter.
2001 & 2002 SCCA, STS Pro Solo National Champion. 2003 SCCA, Solo2 Nationals 8th, co-driver (Courtney) 2nd in 03 & 04
2003 JCW 210, London Stainless Headers, custom cat back with 5" SuperTrapp, 15x7.5 SSR's and 16x8 ce28n's, Quaife, KW Comp 2 Ways
Hi Guys, As regards 'the cylindrical part of a filter' or 'the panel of a panel filter'. I rate the cotton gauze type (K&N JR Green etc) much higher than than foam (pipercross etc) ,it has more surface area, (the corrugated in&out zig- zigs) and less restriction. Also foams when they start to get dirty become very restrictive. This is why we use cotton gauze for the main part of our filter. The foam part of the GTT Cold Ram system is an additional intake zone across the end of the cylinder ,which most intake systems dont even have (ie its blanked off !). This is a reticulated foam circular filter. Easily replaced/ cleaned. The replacements are only £5 so you could replace it once a year for ultimate performance without breaking the bank if you wanted to.
Best Regards Roland GT Tuning
But my concern is that if this circular foam doesn't filter as well as the rest of the filter, then we are potentually allowing dirt into the engine. You said yourself that foam does not filter as well as cotton gauze. If the foam part of the "filter unit" is the path of least resistance, then most of the air will go through it.
Hi,Depends on the ppsi (perforations or pores per square inch) of the foam used. Have no fear,no engine damaging particles will get through . With the GTT kit because most of the air comes from the base of the windscreen rather than the front grille,you will find very little dirt reaches the filter anyway compared to a stock air filter & box. With stock set up after 5000miles the paper panel element is heaving with black dirt. I actually drove my car for 8000 miles with 'naked' GTT Cold Ram kit. ie the GTT box + Rampipe but no filters whatsoever. The result ? no wear to SC ,bores or piston! Not something we would recomemend you do ,but an interesting result. I certainly wouldnt run a stock airbox setup with the panel filter removed.
Best Regards Roland GTT
Remember foam has far more thickness than any other filter design, even the 4 layer gauze is thinner.
The cell structure of foam makes it easier for air to flow around any areas that have collected dirt. If one small cell is clogged wholly or partially there are many cells touching it that allow air to pass and bear in mind that unlike paper or thinner gauze air more easily passes under or around the clogged area.
one dimensional? less restrctive = worse filtering as far as i'm aware unless i miss understand it?
I understand that it's thicker and I understand how the filters work but that doesn't explain how a filter can have good filtering properties (i.e small holes) as well as minimal restriction (i.e. big holes)
I understand the point yer making but that just proves foam filters still flow well when dirty if I read it correctly??
I guess what i dont know yet is how much of the air goes through the gauze and how much goes through the foam on the end of the filter. I guess if is were concerned about air filtering, I could just remove the foam and make a cover preventing air from entering. That way I know the air is being filtered by the gauze. But by doing so, how much more restrictive have I made the GTT filter? Does it achieve such high flow rates because of the foam on the end?
Does anyone have a picture of a dirty filter so we can see where the filtration is taking place?
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.