K&N XStream Flow Through Air Cleaner Lid

[Chargerguy74]

Just wanted to share my experience with the K&N XStream Air Flow assembly I ran on my 440, and hopefully save you some money. Specifically part number 66-3040, 14x3" element with 1-1/4" drop base and flow through lid is what I ran. Throwing this setup on my 440 cost me 43hp. Here you can see the Dyno run with the K&N setup vs the previous run (dashed lines) that was breathing the hot August outside air. Sorry for the poor picture quality, the top HP and torque lines are the dashed lines (previous run). The next run (not pictured) we switched to an Allstar ALL25900 and it immediately gained back 22.5hp (for a total loss of 20.5hp). Shortly after the engine ended up being rebuilt with a new cam and some very minor changes and showed to be relatively unchanged on the dyno, gaining roughly 5hp. This time the ALL25900 only cost 13.6hp. At $100/hr I didn't waste a run on the K&N.



EDIT TO ADD:

Here's where it wound up the second time around, after the new cam and bearings (same grind, Comp XE282S, just new). I went to a 9 keyway crank sprocket which allowed me to set my ICL at 105.25 rather than the 103 I had previously. The power drops right off just after 6000rpm. Some minor changes were done, new rockers, Torrington bearing, went to a louvered windage tray, nothing that made any real difference. Also, switched to an MSD-6AL from the Mopar Chrome box (4 speed, so I wanna have that rev limiter). This is with the Allstar aircleaner.

[myk]

Ive always been suspect of K&N's claims of added power since I've always assumed that an increase in airflow and power should also include an increase in dirt intake.  Now you're telling me that you lose power on top of that?  I knew K&N was full of Bologna...

[firefighter3931]

Those are interesting results 

Does your carburetor have an air horn ? If so....a drop base assembly with a flat top will create some restriction and hurt power. I ran something similar on my old 446 ; K&N filter with drop base and generic flo-thru top but my carb did not have the airhorn (Proform main body) and tested at the track with and without the air cleaner and there was no change in performance.

I now run something similar to the All Star assembly with a K&N element on the big stroker. I like the raised lid design on the All Star but couldn't use it due to hood clearance issues before with the old intake manifold & carb spacer combination that was on the engine at the time. 

It would be interesting to see if the A/F ratios changed switching from one assembly to the other ? Where there any adjustments made on the dyno to jetting ?


By the way....that 440 is making nice power ! Nice work ! 



Ron

[Chargerguy74]

Thanks!

No air horn, carb was a Holley 850 DP. Yes, the change resulted in the AF ratio going richer, from low to mid 13s to low 11s. No jets were changed for the next run with the Allstar and the AF ratios stayed around the mid 11s, but yes, lots of jets were changed on the dyno. So I think it was a pretty fair comparison. I'm hoping the domed lid will fit nicely under my bulge hood. $50 isn't too much to pay to find out.

We slapped on a Quick Fuel 850 carb, I think it was a Q series, for a final run and it was already showing more promise than my Holley. I immediately recalled the guy at the parts counter trying to get me into a Quick Fuel carb when I bought my Holley. But all I saw was a pile of Quick Fuel carbs sitting next to him that they wanted to sell and didn't trust his opinion. They were cheaper too.

[XH29N0G]

Can you clarify for someone who does not fully understand the test?  Was the original test done without an air cleaner at all?  The second with the flow through top, and the next with the radiused top?

[Chargerguy74]

Ive always been suspect of K&N's claims of added power since I've always assumed that an increase in airflow and power should also include an increase in dirt intake.  Now you're telling me that you lose power on top of that?  I knew K&N was full of Bologna...

I was quite surprised myself.

[Chargerguy74]

Can you clarify for someone who does not fully understand the test?  Was the original test done without an air cleaner at all?  The second with the flow through top, and the next with the radiused top?

Yes, you are correct, but not just the top was changed, the base too. Same K&N filter element though. The initial runs (prior to running any air cleaner assemblies) was just running outside air through this setup, here's a pic...

[firefighter3931]

No air horn, carb was a Holley 850 DP. Yes, the change resulted in the AF ratio going richer, from low to mid 13s to low 11s. No jets were changed for the next run with the Allstar and the AF ratios stayed around the mid 11s, but yes, lots of jets were changed on the dyno. So I think it was a pretty fair comparison. I'm hoping the domed lid will fit nicely under my bulge hood. $50 isn't too much to pay to find out.

We slapped on a Quick Fuel 850 carb, I think it was a Q series, for a final run and it was already showing more promise than my Holley. I immediately recalled the guy at the parts counter trying to get me into a Quick Fuel carb when I bought my Holley. But all I saw was a pile of Quick Fuel carbs sitting next to him that they wanted to sell and didn't trust his opinion. They were cheaper too.

I really like the Quickfuel/ProForm carburators....have a QF 1050 on my stroker and it runs great. With the jetting sorted out it's got a nice even A/F ratio in the high 12's - low 13's from 1500 > redline. Idle AFR's I set at 13.5 to keep it nice and clean at idle. 

If it was running in the 11's AFR that would certainly explain the drop off in power. I agree with you that the domed top is better but the significant drop in power can not be totally attributed to the filter top...jetting and AFR's will play a role as well. 

That being said ; my first choice would be the domed top as long as you have enough hood clearance. Sometimes a flat top is the only possible choice so it's a compromise we have to make. 

This is where a wideband O2 sensor really comes in handy by allowing you to make jetting changes and get immediate feedback on how those changes are affecting AFR's and consequently performance. Shoot for high 12's to low 13's on the AFR under load and you'll be a happy camper ! 



Ron

[Chargerguy74]

Makes sense. And with some jetting a bit of that power was gained back. With the domed lid, and jetted properly, there was still a loss of 13hp with the Allstar. Couldn't get it all back.

Time to order up some new exhaust with O2 bungs.

[XH29N0G]

I had an exhaust shop weld in a bung to one of my headers.   

[Chargerguy74]

I have ceramic coated TTI headers with no bungs, and I'm a little nervous about messing with them for this. I've gotta order up a new 3" X pipe system for this motor and will probably have the bung(s) installed a little down stream of the headers.

[myk]

I have ceramic coated TTI headers with no bungs, and I'm a little nervous about messing with them for this. I've gotta order up a new 3" X pipe system for this motor and will probably have the bung(s) installed a little down stream of the headers.

Couldn't they just weld the bungs into the beginning of the X pipe?

[Chargerguy74]

I'm thinking that'll be the best place. Downstream of the X I might add electric cutouts also. I'll decide when I get there.

[myk]

Please update us on what you decide; I need to get bungs installed as well...