Found a way to drop my gearing....

[Hellcat]

Air filter setup     stock filter with metal screen removed. Intake air tubes modified to be straight. Airbox lid modified, stock opening sealed, two holes 1 3/4' ea drilled into front of lid. requires re-jetting and tunning. 

Ignition mods      modified stock TW for 6 degrees, with dyna, curve 7, +10 degrees at hwy speeds. -10 degrees curve is +/-1 degree compared to stock I/S ICM. stock coils. did have CBR1100xx coils, but they kept burning out the dyna, although spec wise they shouldn't have.

Any write-ups out there about the air filter mod? And can you run 87 gas with your ignition mods?

87 octane all of the time no problems.  just pop the metal screen off to increase airflow. And the filter last much longer than the 12k honda says.

any idea how the k and n compares to that mod?

[98valk]

any idea how the k and n compares to that mod?
[/quote]

K&n lets in too much dirt, its a race track item. oil anaylsis will show how much dirt it allows into an engine.

The oem filter is a great filter, it provides plenty of airflow due to its large surface area and airbox, my bike dyno'd 100 HP. This is the marketing trick K&N used yrs ago. they found a car with an undersized aircleaner/filter which restricted top end power. Put in a k&n or no airfilter, more airflow, more power. So the marketing result was a K&n filter in any application increases HP, which is just not so.  this is good to read http://www.rc51.org/airfilt.htm
some links
http://www.ibmwr.org/otech/airfilter.html

http://www.lubespecialist.com/airfilt.htm

http://www.fordmuscle.com/archives/2000/01/airfilters/index.shtml

http://www.safari4x4.com.au/80scool/tech/filters.html

http://www.donaldson.com/en/index.html

http://www.baldwinfilter.com/

http://www.gadgetonline.com/airinduction.htm

http://vettenet.org/knfilter.html

http://www.seansa4page.com/resource/airfilter.html

http://www.seansa4page.com/frames/autotechmain.html

http://www.uti.com/~hoser/K%26N4.htm

http://uaf.com/   Good tech

http://www.bmwe34.net/E34main/Upgrade/Air_filter.htm

http://www.ramair filters.com/frames.html   Click on filter facts

http://www.filtnews.com/

http://theoildrop.server101.com/cgi/ultimatebb.cgi  Great oil and Air filter forums

http://www.dirtcheapracing.com/tech/airfilter/

http://www.bolhuijo.com/airflowtest/index.html

http://www.mcagraphix.com/filter/test.htm

http://www.cummins.com/na/pages/en/customerassistance/faq/answers.cfm?uuid=00060D72 0093 1B8D BCF080C4A8F00000

http://dieselplace.com/forum/forum_posts.asp?TID=10642&PN=1&TPN=4