What size K&N for 3100 is optimal?

Post information about intake systems. Either purchased or custom made
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IsaacHayes
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What size K&N for 3100 is optimal?

Post by IsaacHayes »

What size K&N cone filter is optimal for a 3100 motor? I know bigger is better, but with in reason folks. Is 7" min, or would smaller still work near as good?

I have a drop in and it seems to have about the same surface area as my rather small K&N cone. The drop-in makes a LOT more power with my modified air box than the cone that just sits in the engine bay.

I'm thinking if I move it to the fender to get cold air, is the size going to rob me of much power too? Should I sell it and get a larger one... Or not bother.

I basically want as much power as my modded air box w/drop in or more, but only in a cone as I like that sound!


Image Image 2010 project (click pic)
1994 3100 BERETTA. 200,000+ miles.
16.0 @ 84.41mph when stock. Now ???
Original L82 w/LA1, LX9, & LX5 parts!!!

soon to be OBD1 tuned...
rweatherford
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What size K&N for 3100 is optimal?

Post by rweatherford »

If you really want to know here's how you do it....

Make your Cold air kit.  Then tap into the pipe, hose, etc.... with a Manometer near front of the TB. (not behind it)  You need something that reads in inches of water or other similar fine measurement.

You can test to see which intake system and filter combination works better than the other.  Remember you want the coolest air and with little restriction.  The restriction will show up in your "meter".

I can explain how to make your own manometer from a ruler and some clear tubing if you want.  Searching on yahoo will help you understand how little of a pressure you will be measuring.  Good luck!


Rex Weatherford
92 Beretta GTZ Quad4 Turbo / 5-speed (sold)
Best 1/4 ET =  13.523 @ 105.16 mph

07 Mazda 5 Black on Black (it's slow)

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IsaacHayes
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What size K&N for 3100 is optimal?

Post by IsaacHayes »

Hmm. Neat idea Rex. I was looking more for a general reccomendation though hehe.

I am thinking about buying a Vacuum/Boost meter (20 inHg vacuum, and 10 inHg boost) so I could unhook it from the manifold and put in in the rubber tube before the TB. (I have a spare one so I could just make a hole). That way I could read it from the dash of the car when doing WOT runs.

Would that be sensitive enough?  (and yes I know 10" HG is only ~5 psi, but I don't plan on boost for this motor, at least not anything over 6psi!).





Image Image 2010 project (click pic)
1994 3100 BERETTA. 200,000+ miles.
16.0 @ 84.41mph when stock. Now ???
Original L82 w/LA1, LX9, & LX5 parts!!!

soon to be OBD1 tuned...
rweatherford
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Posts: 720
Joined: Wed Apr 25, 2001 5:39 pm
Location: Shelbina, MO
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What size K&N for 3100 is optimal?

Post by rweatherford »

Probably not sensitive enough to read while driving.

Don't worry, most aftermarket K&N's are plenty large for our engines.


Rex Weatherford
92 Beretta GTZ Quad4 Turbo / 5-speed (sold)
Best 1/4 ET =  13.523 @ 105.16 mph

07 Mazda 5 Black on Black (it's slow)

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IsaacHayes
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Joined: Fri Oct 07, 2005 8:32 pm
Location: Missouri

What size K&N for 3100 is optimal?

Post by IsaacHayes »

The one I have is 3" ID opening, and I think 5" long.... It's no 7 incher that's for sure. I got it off of ebay a long time ago, the guy had it on a BMW. If you were to take the drop in filter I have and wrap it around, it's as big or bigger than the cone!  


Image Image 2010 project (click pic)
1994 3100 BERETTA. 200,000+ miles.
16.0 @ 84.41mph when stock. Now ???
Original L82 w/LA1, LX9, & LX5 parts!!!

soon to be OBD1 tuned...
rweatherford
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Posts: 720
Joined: Wed Apr 25, 2001 5:39 pm
Location: Shelbina, MO
Contact:

What size K&N for 3100 is optimal?

Post by rweatherford »

If you want to figure surface area then you have to take into account the depth of the pleats too.

Sounds like it might be a little small though if it is smaller than your factory filter.  Hard to say without testing....  


Rex Weatherford
92 Beretta GTZ Quad4 Turbo / 5-speed (sold)
Best 1/4 ET =  13.523 @ 105.16 mph

07 Mazda 5 Black on Black (it's slow)

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IsaacHayes
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Joined: Fri Oct 07, 2005 8:32 pm
Location: Missouri

What size K&N for 3100 is optimal?

Post by IsaacHayes »

I believe the depth of the pleats is the same for the K&N Drop-in and the K&N Cone.

I went for a couple WOT runs today and it feels like it has less power on the high RPM's right before shift than it does with the air box... at least from what I remember. It feels like power falls off right before upshift, were as before it felt like it was still building, and when it upshifted the car jumped ahead. That leads me to belive it's restricting flow more... I wouldn't think that the extra heat from the cone setup would choke out high RPMs like that, it would be even power loss across rpms...

This is all what I feel/think and could be wrong though :P
I'll run with the cone a few more days and then swap the box back on and test it out some more with the butt-dyno.

BTW this is the gauge I bought. Only goes up to 5psi (10" HG) of boost, but I mainly just want to see that needle sweep 180* hehe. That and I might get better MPG as I can watch it and try to keep the vacuum high as I can while driving. (ie, stops me from getting on it so much). (like that will happen, I'll probably get on it more to see the needle spin to 0!)   I just gotta figure out how/where to mount it....

Oh yeah I'm leak free too!! haha I need to update my sig!!
Thanks again for your help Rex!! Interior goes in tommorow!!  





Image Image 2010 project (click pic)
1994 3100 BERETTA. 200,000+ miles.
16.0 @ 84.41mph when stock. Now ???
Original L82 w/LA1, LX9, & LX5 parts!!!

soon to be OBD1 tuned...
rweatherford
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Posts: 720
Joined: Wed Apr 25, 2001 5:39 pm
Location: Shelbina, MO
Contact:

What size K&N for 3100 is optimal?

Post by rweatherford »

NP.  Glad you get to enjoy a normal car now...


Rex Weatherford
92 Beretta GTZ Quad4 Turbo / 5-speed (sold)
Best 1/4 ET =  13.523 @ 105.16 mph

07 Mazda 5 Black on Black (it's slow)

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IsaacHayes
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Posts: 975
Joined: Fri Oct 07, 2005 8:32 pm
Location: Missouri

What size K&N for 3100 is optimal?

Post by IsaacHayes »

Yeah, drove it last night after 4hrs of putting the interior back in (phew!).
I forgot how nice it is of a car it's been so long without interior!! It's great to have front speakers again (6.5" at that!) Nice and quite driving around now. Aside from my seat covers the interior of my car looks and smells new!!! And the motor/trans runs great as well.

This thread has gone way off topic, but it's mine so  

Do you have any ideas where I could mount that gauge without drilling/permantly attaching it? I'm thinking a pod and bend some metal and shove it under the console on the passenger side that would hold it up next to the heater controls sort of like a cell-phone holder. But I dont' know if it will stand up to the g forces when I hit the corners...


Image Image 2010 project (click pic)
1994 3100 BERETTA. 200,000+ miles.
16.0 @ 84.41mph when stock. Now ???
Original L82 w/LA1, LX9, & LX5 parts!!!

soon to be OBD1 tuned...
rweatherford
Registered User
Posts: 720
Joined: Wed Apr 25, 2001 5:39 pm
Location: Shelbina, MO
Contact:

What size K&N for 3100 is optimal?

Post by rweatherford »

I'm sure you can figure something out.     You did fix your leak AND got your interior back in.  


Rex Weatherford
92 Beretta GTZ Quad4 Turbo / 5-speed (sold)
Best 1/4 ET =  13.523 @ 105.16 mph

07 Mazda 5 Black on Black (it's slow)

User avatar
IsaacHayes
Registered User
Posts: 975
Joined: Fri Oct 07, 2005 8:32 pm
Location: Missouri

What size K&N for 3100 is optimal?

Post by IsaacHayes »

Looks like I've got a summer goal or project to accomplish. As if I didn't have enough projects started. Turning out to be even more stuff, but might as well, and might as well get the most gains without pulling the motor.

So I'm going to need a proper CAI. I'll need the extra flow, and I love the sound the K&N open cone gives me. Sounds like a v8 is only how I can descibe it. A guy recently road with me and said my car sounded great, and he's not even a car guy, or one to make comments about cars! My exhaust isn't loud enough to hear inside the car but the cone filter helps make it louder overall which I like.

Anywho, What's the common size to run in the fender? 7"? And what ID opening? I'm going to build a PVC one and paint it black (ABS is better, but can't get it around here)

Rex: I'm thinking once done I'll have to drive to your place again so you can ride around with me, since I didn't get to ride in your car, you can ride in mine!    Or we could meet up half way in Columbia perhaps? Probably be the first 3500 frankenstien beretta you'll see. I'm not expecting monster gains, but stock my motor is pretty fun, so with the extra power I'm getting excited.  

I think you should weld me up some custom headers so when I drive down I can slap those on too!! ROTFLOL That way the drive back will be even more thrilling!! hah!

Well, got to research a few more things since the parts list keeps building up. Might as well do a few more things while I'm in there to make it worth my time and the cost of the damn lower intake gasket!!

-Isaac


Image Image 2010 project (click pic)
1994 3100 BERETTA. 200,000+ miles.
16.0 @ 84.41mph when stock. Now ???
Original L82 w/LA1, LX9, & LX5 parts!!!

soon to be OBD1 tuned...
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