Performance air filter
- Thread starter ace
- Start date
No. Don't just drop in a cone filter. Cone filters alone will decrease power becuase they will suck in WARMER air. The stock airbox is desgined by engineers to be as efficient as possible while not being loud. A standard cone filter will hurt your performance, but if you got a cold air intake to a cone filter, or purchased one of the available shields from many of the companies who make cold air intake systems, you won't have that problem.
Max you'll get with a real cold air intake on a given day is 1 - 2 crank hp, which is almost not noticeable at the wheels. Not only that but without a proper setup (to draw air from OUTSIDE the very hot engine compartment), you will notice a negative effect on power. What it WILL do is sound a HELL of a lot better![[hihi]](/images/smilies/icon_smile_hihi.gif "Hi Hi [hihi]")
Honestly it's stupid IMO to waste your money on an expensive aftermarket intake system. All bmw's airboxes have an intake trumpet which pulls cooler air in from behind the headlight, so if you got a drop-in K&N filter (if you aren't worried about the possible extra dust it will allow in) it will be as big of a difference. Unless you have a ported and polished head, AFM upgrade, big throttle body, larger injecters, exhaust headers, and a chip... its not going to be worth the $150 for a good CAI.
These links go for any car. Remember, I'm not saying it isn't effective, but without the proper setup, it will have a negative effect on performance.
http://www.bmwe34.net/e34main/upgrade/Air_filter.htm
http://www.bmwe30.net/cgi-bin/datacgi/database.cgi?file=articles&report=view&ID=00115&Section=03
This is about ram air.
http://www.bmwe30.net/cgi-bin/datacgi/database.cgi?file=articles&report=view&ID=00004&Section=03
Max you'll get with a real cold air intake on a given day is 1 - 2 crank hp, which is almost not noticeable at the wheels. Not only that but without a proper setup (to draw air from OUTSIDE the very hot engine compartment), you will notice a negative effect on power. What it WILL do is sound a HELL of a lot better
Honestly it's stupid IMO to waste your money on an expensive aftermarket intake system. All bmw's airboxes have an intake trumpet which pulls cooler air in from behind the headlight, so if you got a drop-in K&N filter (if you aren't worried about the possible extra dust it will allow in) it will be as big of a difference. Unless you have a ported and polished head, AFM upgrade, big throttle body, larger injecters, exhaust headers, and a chip... its not going to be worth the $150 for a good CAI.
These links go for any car. Remember, I'm not saying it isn't effective, but without the proper setup, it will have a negative effect on performance.
http://www.bmwe34.net/e34main/upgrade/Air_filter.htm
http://www.bmwe30.net/cgi-bin/datacgi/database.cgi?file=articles&report=view&ID=00115&Section=03
This is about ram air.
http://www.bmwe30.net/cgi-bin/datacgi/database.cgi?file=articles&report=view&ID=00004&Section=03
I don't think cone filter is a goor idea unless it's isolated by a heat shield from the engine. The standard air box setup lets you get colder air than just a cone filter. The box gets the air from the outside thru the front grill while cone gets it from the hot engine compartment. Don't think you are smarter than BMW engineers, stock air filter setup is pretty good.
epj3 said:
No. Don't just drop in a cone filter. Cone filters alone will decrease power becuase they will suck in WARMER air. The stock airbox is desgined by engineers to be as efficient as possible while not being loud. A standard cone filter will hurt your performance, but if you got a cold air intake to a cone filter, or purchased one of the available shields from many of the companies who make cold air intake systems, you won't have that problem.
Max you'll get with a real cold air intake on a given day is 1 - 2 crank hp, which is almost not noticeable at the wheels. Not only that but without a proper setup (to draw air from OUTSIDE the very hot engine compartment), you will notice a negative effect on power. What it WILL do is sound a HELL of a lot better
Honestly it's stupid IMO to waste your money on an expensive aftermarket intake system. All bmw's airboxes have an intake trumpet which pulls cooler air in from behind the headlight, so if you got a drop-in K&N filter (if you aren't worried about the possible extra dust it will allow in) it will be as big of a difference. Unless you have a ported and polished head, AFM upgrade, big throttle body, larger injecters, exhaust headers, and a chip... its not going to be worth the $150 for a good CAI.
These links go for any car. Remember, I'm not saying it isn't effective, but without the proper setup, it will have a negative effect on performance.
http://www.bmwe34.net/e34main/upgrade/Air_filter.htm
http://www.bmwe30.net/cgi-bin/datacgi/database.cgi?file=articles&report=view&ID=00115&Section=03
This is about ram air.
http://www.bmwe30.net/cgi-bin/datacgi/database.cgi?file=articles&report=view&ID=00004&Section=03
Max you'll get with a real cold air intake on a given day is 1 - 2 crank hp, which is almost not noticeable at the wheels. Not only that but without a proper setup (to draw air from OUTSIDE the very hot engine compartment), you will notice a negative effect on power. What it WILL do is sound a HELL of a lot better
Honestly it's stupid IMO to waste your money on an expensive aftermarket intake system. All bmw's airboxes have an intake trumpet which pulls cooler air in from behind the headlight, so if you got a drop-in K&N filter (if you aren't worried about the possible extra dust it will allow in) it will be as big of a difference. Unless you have a ported and polished head, AFM upgrade, big throttle body, larger injecters, exhaust headers, and a chip... its not going to be worth the $150 for a good CAI.
These links go for any car. Remember, I'm not saying it isn't effective, but without the proper setup, it will have a negative effect on performance.
http://www.bmwe34.net/e34main/upgrade/Air_filter.htm
http://www.bmwe30.net/cgi-bin/datacgi/database.cgi?file=articles&report=view&ID=00115&Section=03
This is about ram air.
http://www.bmwe30.net/cgi-bin/datacgi/database.cgi?file=articles&report=view&ID=00004&Section=03
BTW, are you sure than K&N lets much more dust than stock filter, I just dropped K&N in my air box yesterday and I don't feel any difference other than engine is louder a bit. I'd rather switch back to stock filter if it lets less dust inside of the engine.Air filter
Thanx for the input guys.....I see there are pros and cons to it.....
My car has done bout 120,080km . I havent changed the stock air filter. Is it necessary to change it?
Is there any other way I can achieve a significant increase in HP, besides the intake, exhaust and chip? wat bout spark plugs???
cheers!
Ace
Thanx for the input guys.....I see there are pros and cons to it.....
My car has done bout 120,080km . I havent changed the stock air filter. Is it necessary to change it?
Is there any other way I can achieve a significant increase in HP, besides the intake, exhaust and chip? wat bout spark plugs???
cheers!
Ace
bmw555 said:
huh, you replied first BTW, are you sure than K&N lets much more dust than stock filter, I just dropped K&N in my air box yesterday and I don't feel any difference other than engine is louder a bit. I'd rather switch back to stock filter if it lets less dust inside of the engine.
BTW, are you sure than K&N lets much more dust than stock filter, I just dropped K&N in my air box yesterday and I don't feel any difference other than engine is louder a bit. I'd rather switch back to stock filter if it lets less dust inside of the engine.
Ace: on the 318is, you will never find much more power, unless you go with the "Downing Atlanta Super Charger", or DASC for short. It's about $3,000 and is a direct bolt on. Gives you about 200 WHP but is super low boost (mostly under 4psi) and has a special air bypass system - so it only builds boost when you need it (ie hard acceleration). But don't waste your money on "performance parts" for the 318. They will not help at all, realistically.
Rule of thumb - anything under a 5 hp gain is not going to be noticeable by "feel". You'll only know it's there by a timed 0 - 60 run or dyno run. Spark plugs, wires, air filter, etc. are all going to be in the 1 -2 hp range, there just isn't a way to get lots of horsepower cheaply. If it was possible, BMW would have given it to you already.
The best "performance" mod is just to make sure it is in perfect stock tune. A poorly tuned car can lose 10 hp easily. If they haven't been replaced in the past few years, spend a few low tech $$ on new plugs, wires (high performance wires might give 1 - 2 hp gain over stock wires), stock or K&N air filter, oil change to synthetic (good for 1 - 2hp over conventional oil) and any other normal maintenance items for the engine. Regarding plugs, there have been various discussions about the high priced platinum plugs. Some people have used them and had a rough running BMW, so stock spec plugs are probably best.
The next best, lower cost gain would probably be a chip.
The best "performance" mod is just to make sure it is in perfect stock tune. A poorly tuned car can lose 10 hp easily. If they haven't been replaced in the past few years, spend a few low tech $$ on new plugs, wires (high performance wires might give 1 - 2 hp gain over stock wires), stock or K&N air filter, oil change to synthetic (good for 1 - 2hp over conventional oil) and any other normal maintenance items for the engine. Regarding plugs, there have been various discussions about the high priced platinum plugs. Some people have used them and had a rough running BMW, so stock spec plugs are probably best.
The next best, lower cost gain would probably be a chip.