Air intake filter kit...

[Greg Gordon]

Measuring acceleration isn't too reliable. The way to test for an air intake system's effectiveness is to measure air pressure and temperature in the plenum.

[maxwedge]

The previous owner of my Celica put one of those cheap ebay filters on it right before I bought it. This is what it looked like 7 months later. It's completely covered in rust if you couldn't tell. I replaced it with a real K&N and couldn't tell any difference except that it looks better. Alfa still has the stock filter on it.

[ghnl]

Quote:

Originally Posted by Greg Gordon Measuring acceleration isn't too reliable.

[RandallM]

Okay Eric,

I didn't know I was going to offend anyone. It was meant for fun and to share my personal experiences. I'm afraid I'm going to have to assume a new name to ever get help again!

Yes. My OEM intake was probably defective, but after removing it twice, for what I thought fixed it, just PO-ed me.

I run these K&N type cold air intakes in everything the family drives. I have fewer maintenance problems and all the vehicles see less hesitation and smoother acceleration.

Have you ever had a car that runs fine except for one gear when the engine stumbles in a certain rpm range? I've seen this type of air cleaner alleviate such problems.

Yes! I'd say the air duct across the top of the engine is the second worst point of restriction. As for the sound of the new air cleaner…you’d get the same throaty sound from your stock air cleaner if you could remove the bottom of the air box. It’s not less filtering, Just a more air availability if the engine requires it.

What were the engineers at Alfa thinking when they ran the intake close to the exhaust, putting a turbo on the Spider?

I once had the opportunity to talk to a Ford Engineer about engines. He provided me with a lot of explanations about intakes, air temps, pressures, fuel mixture, and on, and on, and on. Had an answer for everything why cars are engineered the way they are. Finally, he ended with, “Oh! It also has a lot to do with manufacturing costs.”

Here's what I fashioned for brackets. I used a hacksaw and a drill. I was a little worried about the brackets being weak where I made cuts to bends, but so far so good.

[ghnl]

No offense taken. (or intended, BTW)

I do hate to see folks taken with claims of 'more HP, faster acceleration, greater fuel mileage, bigger penis, etc' by products that are more bling than function.

Have you considered fabricating a true cold air intake/heat shield to go with your K&N replacement?

[RandallM]

Yes I have, but I've got so many other things to get to. I just finished replacing the heater blower. What a job that was!

[DarkWolf40]

I use the K&N just because its reusable and finding air filters of my S4 is not that easy unless you mail order them. Most people don't know how to clean and oil them properly so that is why they get a bad reputation. Also, I believe most of these so called performance enhancement aftermarket filters may show some small increase in HP on a dyno under labratory conditions but are not noticeable in real world driving conditions. People fall for the advertisement expecting majic and then don't and feel jipped.

[Greg Gordon]

In the case of the Alfa Spider, a quality cone filter will improve the sound (that's subjective, but I like it) and add the ability to easily remove and clean the filter. My argument is strictly against the claims of an increase in power.

Greg

[BattleBug]

I too am skeptical of any significant power increases--someone put one on a dyno--let us all know. That said I have one from IAP. IMO, overall a poor value. While the filter and AFM flange are OK. I had to grind away some excess casting bumps and then make my own bracket as theirs is Junk (notice capital J). As far as sound goes, it's better but almost too good--lots of undampened valvetrain clatter when under load--I once gave a blind man a ride and he commented on my "detonation problem". Looks OK when you trash the supplied bracket and make your own.

Soon to have a heat shield.

Paul

[Tifosi]

OT:

Your bay looks better every time you show it Paul. Been cleaning and organizing?


OnT:

I had that setup a while ago and actually found it had more acceleration with the stock setup.

The best those of us who were around when it was on could figure was that the transition of airflow from the open filter was far more violent (free flowing random directional/'un-aligned' air rushing through a big round filter into a dinky rectangular hole that has a flat wall all the way around it) than the stock airbox airflow pattern (sometimes it's even under pressure if you've got the correct plate in there at the radiator mount and the snorkel is present and stuck through the hole) so it was making too much turbulence at low RPM to get any truly worthwhile acceleration (basically the AFM flap was fluttering)

Conversely, the setup does give a little more in the upper RPM ranges, but I couldn't say whether it's power, or just a few more revs that couldn't be attained before.

On the other hand, once the engine is fully warmed up, the soft hose from AFM to the center plastic bit has a habit of collapsing for a moment when you give the throttle a quick whack to WFO.

If folks are worried about restrictions, I imagine that in itself, for that brief time it does it, creates a far bigger one than the airbox would.


Heat shield:

Built one to fit on my header after switching to a SDS EFI system as the combination of filters I ended up using (they draw air from within the engine bay) and given that the SDS has a intake air temperature sensor, I figured it was in my best interest to do so.

Once the sheild was fabbed and in place, intake air temp dropped many degrees. (EG: today it was 88 degrees outside. My intake air temperature was 112 when moving at 55mph and 116 when idling at a light. Pre-shield those temps would have been in the 140-150 range or higher)

Do yourself a favor, put in a shield.

If nothing else, your alternator will like you better for it (that funny back cover it's got with the big tube that points forward is there for a reason.....) and your brake and clutch master cylinders will practically send you flowers.