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Sorry, my reading of the thread was spotty. I did not see where they have not been sold for 6 years and I'm glad they haven't. A lot of my work is repairing/rebuilding 928 motors with scratched cylinder walls - but I don't want that much work!
I do hope DR can get back into it, I believe they would sell also.
"Changing the air filter from pleated paper (commonly filters down to 1 micron) to oil soaked cotton (commonly filters down to 10 microns) has always been a quick way to pick up some HP"
There is a total count of 0 Dyno charts to support this statement.
There are a Non-0 count of Dyno charts on paper filters showing significantly higher than stock HP on the OEM paper filter.
"Changing the air filter from pleated paper (commonly filters down to 1 micron) to oil soaked cotton (commonly filters down to 10 microns) has always been a quick way to pick up some HP"
There is a total count of 0 Dyno charts to support this statement.
There are a Non-0 count of Dyno charts on paper filters showing significantly higher than stock HP on the OEM paper filter.
I think you may have misunderstood what I said. What I meant was that - for a long time now, removing a pleated paper filter and replacing it with a oil-soaked-cotton filter to gain HP has been a common theme. K&N has built their whole business around it.
The oil-soaked cotton lets more air through, hence, more HP. It also allows more dirt through. So it is VERY important where oil soaked cotton filters are concerned that you use a quality product, with high density and a lot of surface area.
Carl if you read the thread you would know that they have not been sold for over 6 years now.
Still have the system fitted to three of my own cars with zero issues and not heard back from customer regarding any other issues.
Yes you have to keep on top of the crud in the filters but that is normal maintenance.
Very happy with the setup - economical and looks great. No HP gains and we never sold it based on HP gains - just the bling factor.
I must get three emails a week asking for me to supply - you can check out the various threads. If DR made his system it would sell like hot cakes.
The system was designed by Rennlisters and we just made it available. Still looks pretty good to me on my daily driver.
I put one of yours on Daniels car and it looks awesome. It just required more attention to detail when installing, fit fine on his 89.
I agree with everyone else, if DR or someone started selling a kit it would sell like crazy. I would love one for my 87.
...why cant you use the stock air-box, and cut the pleating out of a stock filter (re-use the gasket portion to seal the lid), then make new hoses with in-line filters?
Hi Carl - Do you have a picture of the EIS system you were checking out? Those filters do not look the same as on my EIS system. Looked at the filters today (I needed to clean them after your timely reminder) and they fit very well with no way for unfiltered air to bypass them.
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
I think you may have misunderstood what I said. What I meant was that - for a long time now, removing a pleated paper filter and replacing it with a oil-soaked-cotton filter to gain HP has been a common theme. K&N has built their whole business around it.
The oil-soaked cotton lets more air through, hence, more HP. It also allows more dirt through. So it is VERY important where oil soaked cotton filters are concerned that you use a quality product, with high density and a lot of surface area.
"The oil-soaked cotton lets more air through"
I believe the proper statement is that it CAN present a lower pressure differential between the atmosphere and the intake where it wants to go...
But that's only a plus, if it's a problem to begin with.
I looked before I posted and the pics I posted were the only ones I kept. But I can tell you it looked just like the one Sean posted (below). I will email my customer and ask him to take a picture for me.
Carl's post yesterday prompted me to take a somewhat overdue look at my EIS system given I have not opened it up for quite a while. I have had this system for something like 8 years and covered about 40k km with it I would think.
When I opened the filter housing there was some crap exactly where I would expect it to be at the base of the taper and some gentle tapping of the matrix caused some fines to drop out of it. I need to get some cleaning fluid and filter oil or order a pair of new elements [probably a safer bet].
Design wise the matrix were it to be opened up would have about the same nominal surface area as a stock filter and the same extended surface as the K&N type element they made to fit in the stock airbox. I suspect it is not possible to fit a bigger diameter element - whether a longer one could be fitted in the space available is also doubtful.
I found Carl's comment about Spectre quality a little strange in that the filter housing is superbly made and the filter element is very robust and after 8 years in my 928 shows no signs of degradation whatsoever. Indeed the inner surface of the element was spotless as were the walls of the kit downstream of the element which when wiped with white kitchen tissue showed no pick up whatsoever. That does not mean there is nothing getting through but it is a healthy indicator. The filter element itself is tested to what I understand is the de-facto test specification for air filter elements [ISO 5011] for whatever that is worth. . As to what level of particle size they remove I cannot comment but the important bit is that they should remove particles to a size level that does not cause damage thus if one element outperforms the other it is only relevant if that difference is critical. I am sure Roger would have done some research in this regard and needless to say the original concept that Dave came up with uses the same filtration mechanism. If they were useless I doubt any of the filter makers would still be in business but I can well believe some systems are oversold as it were.
Performance wise my experience was that the EIS system has a healthier pick up- nothing earth shattering- just a subtle improvement. My interest in this concept came about because it seemed to me that the stock airbox is not a good design, rather it is something shoe horned into the available space. For folks who have some knowledge of fluid flow this is not difficult to reason. The stock airbox is too shallow to work as an effective plenum and airflow over the filter element is far from uniform and far from ideal considering the MAF sits directly underneath given flow instruments do not like flow disturbances immediately upstream thus an inlet like the one on the EIS /Dave's system makes a lot of sense to me. The only thing I found surprising was the idle seemed to be a tad worse than the stock system. Fitting a honeycomb at the inlet to the MAF stabilises the idle but I felt it lost the pick up the mod created in the first place.
The only real issue I had with the EIS system was the height of the inlet tee piece that seemed to foul on the bonnet. I resolved that by leaving out the rubber O ring. The flange of the tee piece is such that it is a tight fit over the MAF inlet and in fact I had to work it a bit to even get it mounted. Seemed to me nothing was going to get through that joint so I put a smear of vaseline over the joint face and left off the O ring to gain a couple of mm and that seems to work just fine.
Below a few pics Inside of the filter element Spotless inlet duct Filter housing outlet matches diameter of filter outlet [4 inches]
Carl's post yesterday prompted me to take a somewhat overdue look at my EIS system given I have not opened it up for quite a while. I have had this system for something like 8 years and covered about 40k km with it I would think.
When I opened the filter housing there was some crap exactly where I would expect it to be at the base of the taper and some gentle tapping of the matrix caused some fines to drop out of it. I need to get some cleaning fluid and filter oil or order a pair of new elements [probably a safer bet].
Design wise the matrix were it to be opened up would have about the same nominal surface area as a stock filter and the same extended surface as the K&N type element they made to fit in the stock airbox. I suspect it is not possible to fit a bigger diameter element - whether a longer one could be fitted in the space available is also doubtful.
I found Carl's comment about Spectre quality a little strange in that the filter housing is superbly made and the filter element is very robust and after 8 years in my 928 shows no signs of degradation whatsoever. Indeed the inner surface of the element was spotless as were the walls of the kit downstream of the element which when wiped with white kitchen tissue showed no pick up whatsoever. That does not mean there is nothing getting through but it is a healthy indicator. The filter element itself is tested to what I understand is the de-facto test specification for air filter elements [ISO 5011] for whatever that is worth. . As to what level of particle size they remove I cannot comment but the important bit is that they should remove particles to a size level that does not cause damage thus if one element outperforms the other it is only relevant if that difference is critical. I am sure Roger would have done some research in this regard and needless to say the original concept that Dave came up with uses the same filtration mechanism. If they were useless I doubt any of the filter makers would still be in business but I can well believe some systems are oversold as it were.
Performance wise my experience was that the EIS system has a healthier pick up- nothing earth shattering- just a subtle improvement. My interest in this concept came about because it seemed to me that the stock airbox is not a good design, rather it is something shoe horned into the available space. For folks who have some knowledge of fluid flow this is not difficult to reason. The stock airbox is too shallow to work as an effective plenum and airflow over the filter element is far from uniform and far from ideal considering the MAF sits directly underneath given flow instruments do not like flow disturbances immediately upstream thus an inlet like the one on the EIS /Dave's system makes a lot of sense to me. The only thing I found surprising was the idle seemed to be a tad worse than the stock system. Fitting a honeycomb at the inlet to the MAF stabilises the idle but I felt it lost the pick up the mod created in the first place.
The only real issue I had with the EIS system was the height of the inlet tee piece that seemed to foul on the bonnet. I resolved that by leaving out the rubber O ring. The flange of the tee piece is such that it is a tight fit over the MAF inlet and in fact I had to work it a bit to even get it mounted. Seemed to me nothing was going to get through that joint so I put a smear of vaseline over the joint face and left off the O ring to gain a couple of mm and that seems to work just fine.
Below a few pics Inside of the filter element Spotless inlet duct Filter housing outlet matches diameter of filter outlet [4 inches]
Filter element
.
That's exactly what I see on the dozens we have around here. Clean inside. Hell, had Andy Kays out of his car 2 weeks ago, to clean the filters because he said he had 20k miles on it the past 1.5 years. Filters were obviously dirty but the post filter areas were just fine. Sounds like someone had an installation issue as it's easy to get the filters in a bit crooked if you don't pay attention.
09-10-2018, 05:47 PM
George Layton March 2014
