K&N Air filter for a 94 348 Spider????

Hi
Try Scuderia Systems. They de-catted my 1994 348 and fitted a Tubi, with their own F1 style air filter. Its all good for between 10 & 15 BHP gain. And, it sounds awesom.

 

K&N does make a 348 air filter, though it may be a Euro-only option. I bought mine from an F-owner in California via eBay. He had purchased a bunch of the Euro K&N filters for the 348. Cost me $30 new + shipping. Cheap and easy. It is a much better fit in the stock airbox than the factory paper air filter, too. Very tight. Just right.

There are LOTS of things that you can do to these cars to speed them up. See the thread on Sub 5 second 0 to 60 for 348's. Also, click on the web pages of various 348 owners, as some of them have performance tips buried there.

For instance, while changing out your air filter, you can remove the four protective screens that cover the front and backs of the two MAFs that get their air input from through your air filter.

NGK Iridium and Splitfire spark plugs can also be gapped hot (around .0285 inches) for another boost.

You're going to want to pop the two blue disposable caps on your two MAFs to adjust your air to fuel ratio, too (you will need access to an exhaust gas analzyer).

Thinner engine oil helps (e.g. Red Line's 5w30 synthetic) free up torque (less friction)...ditto for better gear oil (e.g. Royal Purple or Red Line's synthetic SuperLight Shockproof 70w90) which also improves your shifting speed and ease (especially cold).

Changing out your factory catalytic converters and exhaust system will probably be your best bang for your performance buck, though 348 Spiders aren't as in need of the better mufflers as are the earlier 348's.

These are GREAT cars! You'll love tweaking your 348. Changing the spark plugs, for instance, is easier on the 348 than on *any* other V8 car ever made.

 

Is the K&N air filter just a straight swap of the filter element into the standard box?

If it is, then I presume the sound is unaltered?

Are there any 348 options that swap the airbox itself to improve sound? Just curious

Jas

 

I want to try these at some point but don't have any real world feedback from someone who's used them yet....

http://www.bmcairfilters.com/ use the pull down menus to get to 348.

Cheers
Kevin
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I've "heard" (heh, heh) several F-car owners mention a difference in sound by changing from stock to K&N.

For myself, I didn't notice a thing, but in all fairness, my ears aren't the world's sharpest so it may just be that I don't notice a difference. It may also be that my 348 Spider is surprisingly well insulated.

The K&N filter simply replaces the stock Ferrari paper air filter; there are no changes to the airbox itself.

I'm not a big fan of replacing the stock airbox, though there are some aftermarket options for that.

 

I haven't tried those air filters, but I have a conceptual problem with going to two separate air filters...because you lose the stock airbox ability to equalize airflow.

You don't want half of your 348 engine air intake getting 75% more of your air than does the other half, something that *could* happen in that sort of 2 filter system that has no way of equalizing pressure.

Something as simple as debris blockage or wind gust direction could cause the setup that you pictured to have uneven amounts of air in one side of your engine versus the other.

In contrast, the stock Ferrari 348 airbox draws all air in to a common area, filters it, and then draws all intake air from that filtered mass of air. In this setup, a debris blockage would reduce airflow, but that airflow would be reduced EQUALLY to both sides of your engine.

So in the worst case with using the stock airbox, you'd simply suffer a power decrease... but no engine-damaging dynamics due to half of your engine operating at 100% while the other half operated at 50%...a condition that a 2 air filter system *could* experience.

 

I think you're overreaching on this one...

Cheers
Kevin
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Perhaps, but doesn't the TR have an air equalization tube running between its independent air filters?

 

Uh ...... thats a picture of a '95 355. Plus the 348 has an equilization valve in the middle of the intake plenum.

 

Here are Testarossa, 512TR and 512M engine pix - not that great but just did this quick - and I don't see any tubes.

Cheers
Kevin
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True, but that eq valve is adjusted for a preset condition about once every 30,000 miles. It's only going to do so much to mitigate a large difference in air suddenly going in one half of your engine but not the other.

Still, the pics showing independent factory air boxes in other F-cars makes me agree with the poster who said I was perhaps overreaching on my concern for this issue.

 

Uhhhhhh???? You don't know what you are talking about. There isn't any adjustment every 30,000 miles. The valve runs off a vacume. The only preset condition is in the ecu, and that is for the valve to open and close at a certain rpm to help with torque.

 

Perhaps you are confusing the 348's intake compensation solenoid (automatically active from 3,500 rpm up to 5,500 rpm) with the 348's manual air intake bypasses (one on each bank of cylinders).

See Page #C36 in the 348 Factory Workshop Manual on "Idle Adjustment"

 

Okay dude now your fishing.

The intake bypass valves are to help the cats warm up faster. They also function off a vacume and are regulated by the coolant temperature sending units. There is no adjustment for them as they only opperate when the engine temperature is below a given level.

The idle adjustment valve is on the throttle bodies, and has nothing to do with the intake compensation valve inside the intake plenum. The throttle bodies do get balanced, but the intake compensation valve does not.

Yes I have a manual, and no the manual does not say that the intake compensation valve get adjusted every 30,000 miles.

 

Mine has the K&N filter....i just clean it out today...it was fooking well dirty!!!!...Compressed air sorted it...then a hose down..then dry in the sun...good as new Is a really good fit to the box.....many cars the filter just flops in!

 

The factory workshop manual says to manually open the intake bypass of the bank with the lower pressure. This bypass has a lockdown screw that must be tightened after the pressure between the two banks has been manually equalized.

This bypass adjustment is performed while the intake compensation solenoid is disconnected.

See Pages C34 to C36 of your Factory WM for your 348.

 

Compressed air can clean out your K&N...and also ruin it by punching holes through the cloth.

Best to just soak K&N filters in water and then allow them to air dry.

 

No doubt...no doubt you are right LOL....BUT it was done with that in mind...so hopefully no problems...visably looks ok.....but even if it did do a few holes the particle has got to get thru them wire mesh gates that are further along

 

Yeeeees I know this. Like I said the throttle bodies do get adjusted/balanced. The reason the compensation valve gets locked down is so that you can balance the pressure between the two throttle bodies. If the valve is close you will not be able to do this, because the pressure between the two sides of the plenum is shut off via THE INTAKE COMPENSATION VALVE.

But as I said in the first place the compensation valve DOES NOT get adjusted every 30,000 miles as you suggested. But since you can read the shop manual so well, if you please tell me were the "secret" adjustment screw for the intake compensation valve is located, and what does it get set to, so that we all can set it. NOT the throttle bodies, which you keep refering to, the compensation valve that is right smack in the middle of the intake plenum. Where is the adjustment for it, and what does it get set to?

 

We're in agreement that the intake compensation solenoid doesn't get adjusted; we're not in agreement that I suggested such an adjustment.

I said something else, that the intake BYPASSES *could* be manually adjusted ocassionally (I used a 30,000 mile figure to that effect).

Your confusion probably resides in mistaking the automatic intake compensation solenoid for the manual intake bypasses.

The automatic intake compensation solenoid is *only* activated between 3,500 rpms and 5,500 rpms. In contrast, our 348's will probably have one intake bypass open all of the time. This intake bypass is adjusted MANUALLY (typically at a Major Service, though it can be performed at other times such as when setting your idle).

Intake compensation solenoid = AUTOMATIC.
Intake Bypass = MANUAL.

Two different beasts, not the same thing at all, and probably the heart of your confusion.

 

Of course they have been posted repeatedly on this board numerous times, but here ya go:

33-2656


You can look up all of the known K&N/Ferrari #'s here:
http://www.ferrariclub.com/faq/knfilter.html

 

Here let me refresh your memory