bsh

iTrader: (1)

Hi

Looking for a small 4" air cleaner for 600-650whp. I do run a pretty big KN now, but want to reroute the air filter and need a smaller one. It must have 4" inlet.
Any recommandations?

Thanks

240Z TwinTurbo

iTrader: (25)

Rule of thumb:
Determine desired flywheel hp, multiple by 1.5, and you get cfm required.

700hp(flywheel) x 1.5 = 1050cfm

You will probably need at least a 9" K&N.

bsh

iTrader: (1)

Thanks, but I meant 4" inlet flange. It seems like KN doesnt give any hp/flow info on the filters...
I could not find any 4" Amsoil filters on Amazon.
What filters are the 600 whp guys running when minimum space are available?

ihockey1

iTrader: (11)

could try the perrin, you would need a 4.5 to 4 adapter tho, its fairly compact and i would say it flows pretty well seeing as its just foam over the end of a pipe

psphinx81

iTrader: (38)

buschur sells one, its what i use

EvoDom

iTrader: (7)

I have a 4" k&n on my car and I made over 600

240Z TwinTurbo

iTrader: (25)

Roger, my reference to 9" is the total length of the filter that is assumed to be flanged for a 4" inlet. While K&N doesn't post flow specs you can call and they make a quick calculation. Their flow numbers relfect 1.5" H2O pressure drop and here is what I found...

K&N RE-0870 (901.67cfm) - 9" long cone filter
http://www.knfilters.com/search/prod...x?Prod=RE-0870

K&N RE-0860 (1202.23cfm) - 12" long cone filter
http://www.knfilters.com/search/prod...x?Prod=RE-0860

With that said people will post they have achieved 600hp@wheels with smaller filters. This may be true, but it is a restriction as compared to a properly sized filter. Same argument you see when English Racing reports 30-40hp@wheels gains when removing the MAF and switching to speed density with no filter.

I think you get the idea, running a smaller filter will hold back power.

apagan01

iTrader: (299)

EA 4560, we have a buch of them

Jrod@Buschur

iTrader: (101)

https://secure.buschurracing.com/cat...oducts_id=1548

240Z TwinTurbo

iTrader: (25)

The Amsoil EA 4560 is a replacement for the K&N version RU 4740:

RU4740 - 582cfm @ 1.5" H2O

I am not sure how much more flow you get from the Amsoil version listed above.

bsh

iTrader: (1)

Thanks all

Jrod
How much hp is it rated to? Looks very interesting.

apagan01

iTrader: (299)

There was a test conducted and ASMOIL came in 2nd out of over 5 filters, in filtration and flow.

many folks running it, with small and big turbos

https://www.evolutionm.net/forums/ev...t-results.html

Jrod@Buschur

iTrader: (101)

We had that filter custom made for us from a BIG name filter manufacturer.

Its the same filter that we run on the BAD BISH... so we know its good over 700whp on our Mustang Dyno.

bsh

iTrader: (1)

Thanks Jrod

That is more than enough for me I will place an order in your webshop.
Thanks

Jrod@Buschur

iTrader: (101)

You're welcome! Thank you for your order.

Glad I could help!