Thread: Are K&N air filters safe ?

Have a look at this site
http://motorcycleinfo.calsci.com/Filters.html
Regards Philip A

Originally posted by PhilipA
Have a look at this site
http://motorcycleinfo.calsci.com/Filters.html
Regards Philip A

STRUTH! doesn't sound good! But i remain unrepentant, on the dyno these things showed a useful HP increase and i'm still getting a good run.

Shaunp - i've heard of the hotwire airflow meter problem (in general) so i can see how a bad airfilter would cause a problem, lucky for me my bike doesn't use one! One sure way to test for dust is to grease the inside of the airbox down from the filter and see what collects, i'll give it a try next time i have it opened up.
I think with any kind of 4WD your better off just using the original setups, my series 3 still has the oil bath and it'll be just fine.

They breath good, like I said we have some big ones on the race car, 383 chev blown, injected, Edlebrock alloy heads etc, 700hp at wheels and that was the last engine the new one has a bigger roller cam and a new Nascar block and a billet crank, the last block crack everywhere even thugh it was grout filled. The throttle bodies flowed 1200 cfm with filters

Originally posted by shaunp
They breath good, like I said we have some big ones on the race car, 383 chev blown, injected, Edlebrock alloy heads etc, 700hp at wheels and that was the last engine the new one has a bigger roller cam and a new Nascar block and a billet crank, the last block crack everywhere even thugh it was grout filled. The throttle bodies flowed 1200 cfm with filters

Excellent! What're your et's? I'm running 9.3's at 240 kmh (ish) using Nitrous or 330kmph top speed. I used to have a Milodon slide rule which could calculate power off those figures but it's missing, if you have one can you give me the reading? I reckon it's into the 200's at the back wheel now. Pushing a 200 kg bike + 100kg rider you know i'm having a good time [img]style_emoticons/<#EMO_DIR#>/laugh.gif[/img] [img]style_emoticons/<#EMO_DIR#>/laugh.gif[/img]

We don't drag it, the engine is in a V12 Etype jag can't get big enough tyres under it to get traction off the line, it does carry the front wheels in to 2nd. The car is used for Hill climbs and Historic street sprints, won Leyburn sprints first outing a couple of years back, broke an axle at Gatton, all 4 wheels a foot of the ground at Speed on the Tweed year before last. Had some trouble getting the injection correct, the map sensor would not respond quick enough when it come on boost and it would go lean, back fire into the manifold then the malpassy fuel reg would think it had heaps of boost would up the pressure to 75psi and it would go rich. I got the firmware of the ecu changed so we could tune just on throtle postion and that fix it. When we dynoed it to make the new fuel maps we noticed a bit of light rattle sounded like crook rocker so we kept tuning. Anyway it had 580 ftbl of torque at 2800rpm with 30% throttle anymore and it would smoke the tyres on the roller (i've got the pictures) and 700hp at 5000rpm at 70% trottle again with the tyres smoking, wrecked a set of RA compound sprint tyres in an hour and a 1/2 on the rollers. So the thing was off it's head. Took it to Noosa hill climb but by 2/3 track it was filling the oil catch tank and spray it over the pipes so we had to back off but Dave was quicker than last year even coasting the last 1/3. Pulled it down and found the noise, one piston was about to loose the top and 6 others had broken ring grooves. The block had lotts of small cracks and it was clear the bearing were starting to move a round.

So got a new "world block" from the US and a billet crank, some Carillo rods to replace the Scat crank and rods and a much bigger roller cam. Also changing the manifold, it was running a B&M blower manifold that we modified to take injectors but it was blowing back between cylinders on over lap, now have a Victor injection manifold but have to do some work to fit the bower on. Blower is an Opticon auto rotor srew chrager.