axl911

I know that the factory air filter is actually the best one. However, for a cone type filter, what is the best one out there available?

I've seen one with "911 GT3 Cup" written on a BMC filter. How is this one and where to get it?

thanks,
anthony

Stealth 993

Waste of time, & money. A lot of cars will loose HP with them.

Any of the higher end brands are Ok, the BMC one will filter the same as the BMC panel filter. Is that what you mean by "best" The BMC one, might in fact be for the Cup cars, since they do not run a air box, or any kind of OEM filter.

What do you want the cone filter for? What do you want out of it?

axl911

Looking to replace the conical filer element for the TPC supercharger.

Steve Weiner-Rennsport Systems

I use a BMC over a K&N, when I have a choice.

axl911

Thanks Steve. BMC is certainly pricier, but is the air filtration better?

As for K&N, I've used them once on my old M3. After finding fine dusts in the intake track after the filter, I ditched it.

Steve Weiner-Rennsport Systems

Close, but BMC's QC and fitment is much better. No oiled-gauze filter will trap the fine stuff anywhere near as well as the OEM paper ones so thats a tradeoff that one must understand.

All of these type filters require a film of grease on the rubber sealing surface to prevent leaks.

TheOtherEric

You're saying that these are actually more restrictive than the factory air filters? I find that very surprising, but I never took a close look at one or saw any dyno testing of the cone type filters.

Stealth 993

Nope not at all. Some may be more restrictive, but who knowns., with out testing.

Most airboxs are set up to take air from a low pressure zone, this gives smooth air to the MAF. When you put in a cone it changes the smooth airflow to one that is more turbulent. This gives the MAF different readings & can cut fuel/timing to a power loss. They also tend to suck in more hot engine air, then the factory boxes, also lessing HP. Most people equate the sound made with the car making more HP. Or the slight increase it can make on throttle response.

I've dyno tested quite a few airboxs & cone type filters on various cars. Cone type filters. on most normally aspirated cars, will loose a little bit of HP, like 2-6. But any car that the factory airbox is becoming the bottle neck they will increase HP, as they loosed up the bottle neck. On a stock 3.6, they are not the bottle neck. If you want the sound of a cone, get the Motor Sound airbox cover.

Basically, you need to build a cone type for the application. Pull in cooler, low pressure air. On a stock engine, it's a waste, for a built engine, or a upgraded forced induction car there are benefits.

axl911

Do you mean a neutral pressure zone instead of low?

BTW, where are the high/low pressure zone in the back of the 993?

TheOtherEric

AFAIK, these cone-type filters will draw air from pretty much the exact same place as the factory airbox (assuming you use a small "L"), so I don't think this hi/lo pressure zone is an issue.

From some runs that I've made, I found that you do indeed pick up a couple hp at the hi end using a less restrictive intake. In my case, I compared a stock setup to a Fabspeed open Cup airbox and K&N filter. I'd imagine the cone could give similar (small) benefit. Of course, it's just a few hp and it's just at the high-rpm range, so it's hardly substantial. But yes, you'd have to test to know for sure.

And FWIW, I switched back to a paper filter and drilled OEM airbox.

trophy

I know with my cone filter it sits directly under the grill, it is drawing air directly from outside the engine bay. Looking at the top of the engine cover you can clearly see all of the filter... It's even better when the wing is extended. Porsche's own "Motor Sound" draws from inside the engine bay.

I am installing an aftermarket ECU at the moment and just about to put an ambient air temp gauge in so i can compare IAT with ambient to see if there is actual increased temperature or internet chatter on the subject.

Macca

Hi Guys.

I wont give my 2 cents here as you will find a recent post and discussion on this subject from me if you hit search.

I suggest MSDS filter if you are running clutch breather tube on pre VRM cars which do not have a filter side oxygen temperature sensor. I have attached a pictur of MSDS latest filter below installed on my car. Its a custom dual cone filter, looks like the K&N/BMC style gause. The quality is excellent and the rubber seat is black - the silver cap is cromed plastic to reduce hat soak. Cost is around $80 from memory. I also bought the BMC filter for the 993. They come in steel or pastic cap (I chose pastic as like the MSDS it will have less heat soak). These are similar to the ones mentioned with "GT3 Cup" on them. They have a red rubber base and are nicely made but no obvious quality difference over the MSDS apart from packaging. The BMC unit has a pre drilled hole in the neck for the post 1995 air temp sensor cars and doe not come with a kit to modify the clutch breathing tube.

I ended up going with the MSDS unit as I dont have the temp sensor. I also abandoned the Clutch breather so simply unscrewed the adpaptor MSDS supplied. Lastkly the red is pretty out there on the BMC filter!

You can order BMC filter using the model number which is part of teh file name below (right click the picture and save to your desktop and you will see it). There is a BMC us online ordering page you can find with google. Its 70 usd from memory - resonably priced I think.

PS. Without having a debate I can say after Dyno testing there wasnot percieveable difference between cone filter as installed below on my car and factory airbox cover with cut out side panels and K&N filter panel. Air temps were the same as its drawing air after those cut outs from exactly the same place. I personally believe heat soak in the factory box (black thick abs plastic) will counter any losses due to different airflow of the cone. The MAF has a grid on the front to straighten airflow. This is the biggest debate topic over the years on Rennlist and I find there alot of smoke blown on this by those who havent tried the options. Personally I like the fact the cone offered less weight, better sound, better throttle response, less space and better airbflow. I also believe it looks great too on a NVR 993. If theres any difference in performance its beow 2hp/2lbft and within the statistical range of error/condition changes.

M

Lorenfb

"I am installing an aftermarket ECU at the moment and just about to put an ambient air temp gauge in so i can compare IAT with ambient to see if there is actual increased temperature or internet chatter on the subject."

And what do you think will result? Hardly takes any brain power to infer that there will be a temp
differential but not of any significance to affect engine performance, e.g. Just like the tweaking
of AFRs with 'performance' chips.

trophy

Well, as you so regularly ask for "Proof" rather than inference, this process will give me proof, measurable, repeatable proof. I wont have to use my brain power 'To Infer' (Inference, now thats some solid scientific reasoning), I will look at the data. I can then use the data to locate the cone filter in the best possible position.

And I thought you said that performance chips only 'Push Ignition' are you saying these tuners are looking at in a more comprehensive way? AFR's, Ignition? Idle? Part Throttle?

It doesn't take any brain power to respond appropriately without insulting people every time you post....

TheOtherEric

Engines take in sooo much air, that I absolutely refuse to believe that moving the air inlet around a bit will have any impact whatsoever on IAT. No way.

So many ways to prove this, I don't know where to begin. For starters, grab an aluminum varioram intake after a 30-minute track session. It'll feel exactly the same temp as ambient. Again, due to the enormous air flow.