I recently change to a smaller filter because of the intake tube I am using will only fit a small 8" filter and not the 12" one. I went to the track and my times are different.

I was running 93-94 mph in the 1/8th with the big filter. Now I am at 89 with the small filter.
The other change is my 60 foot times. I dropped them from 1.9's to mid 1.6's. I know spinning has some effect on mph, but how much?

I suppose I could cut the power pipe, but I don't want to if I don't have to...

 

How was your time? Did it improve? In past experiences when my 60ft improves my mph drops. You are showing a huge improvement in your 60ft. You hooked hard. Probably more related to the track condition vs the pipe/filter. Then again if the pipe/filter drops your time by .3 how bad is that.

 

--Joe

 

On the freeway and the track it feels as though it is dragging at higher speeds... So I was thinking it might be the filter. I changed the tires so that is why the 60 foot times went down. My ets dropped about 2 tenths.

 

I thought that if my 60 foot times dropped 2 tenths then my 1/8th mile times would drop more than 2 tenths...That is why I have this filter size question in my head. Also if you do the math for what K&N recommends they say I need a larger filter for the 567 rwhp...

 

I understand that is you drop 2 tenths 60' you should see approx. 4 tenths drop in your ets... that is 1/4 mile.

As far as what k/n says... I don't think they take into account a forced induction motor. If you have the proper flow of fresh air , then that is what matters most (my opinion of course).

If my memory serves me right; Sal from PSP showed that a stock setup actually loses power with a cone type filter setup.... and that the main problem is the hot engine air being sucked up by the motor...
Good Luck,
John