Which filter with a ram air kit?
Which filter with a ram air kit? I'm getting ready to order a FTRA kit for my LS1. Without a pressurized system I've found that there is little difference between a paper filter and a K&N or Holley filter. My question is now that I'll have a ram air kit and a "pressurized" induction system, is it worth going to one of the more expensive filters?
I should say do you see performance gains with a K&N filter when you add a FTRA or is the gain still negligable with this filter..even with the pressurized induction?
For you technical types out there, does the pressure drop across the filter come into play now that I have a FTRA?
Thanks.
<small>[ June 11, 2002, 05:33 PM: Message edited by: equandt ]</small>
I should say do you see performance gains with a K&N filter when you add a FTRA or is the gain still negligable with this filter..even with the pressurized induction?
For you technical types out there, does the pressure drop across the filter come into play now that I have a FTRA?
Thanks.
<small>[ June 11, 2002, 05:33 PM: Message edited by: equandt ]</small>
Re: Which filter with a ram air kit? I saw a minimal difference between paper and
the Donaldson filter in my "Shop Vac Test".
That is, at whatever flow rate the shop vac
was capable of, [totally uncalibrated, but
relatively repeatable] These are the pressure
drops I recorded, in inches of water:
Lid, no filter: 0 - same as open shop vac port
Lid, Donaldson: 1/2"
Lid, Purolator: 3/4"
Lid, Fram: 7/8"
Lid, OEM: 7/8"
By comparison:
OEM Lid, open: 1-1/8""
MAF with screen: 2"
The Oiled membrane filters will be somewhere
between the paper filters, and nothing. Yeah,
you could gain a whole 1/2" H2O of pressure.
That's like, what, 0.02PSI of boost. Maybe the
intake flows twice as much as my shop vac. Call
it 0.04PSI. Our throttle area is < 2X as big.
On the supercharger price/performance scale,
you're looking at something like $300 per PSI
of boost.
So if the filter costs more than $12, it's more
expensive per lb of boost - incremental horse-
power - than a supercharger.
From what I read, each PSI of boost looks good
for maybe 30 HP. Sanity check this as 325HP stock
HP / 14.7 PSI = 22 HP/PSI.
So using the latter, the ultimate filter [zero
drop] would give you about 22HP/PSI*0.04PSI or
1HP over the better paper ones.
Woo-hoo! Ain't science fun?
I put the Donaldson in a box and run with the
Purolator since that last horsepower isn't
someting I use often and the filter's not
cheap [I dunno if I can even get a replacement].
the Donaldson filter in my "Shop Vac Test".
That is, at whatever flow rate the shop vac
was capable of, [totally uncalibrated, but
relatively repeatable] These are the pressure
drops I recorded, in inches of water:
Lid, no filter: 0 - same as open shop vac port
Lid, Donaldson: 1/2"
Lid, Purolator: 3/4"
Lid, Fram: 7/8"
Lid, OEM: 7/8"
By comparison:
OEM Lid, open: 1-1/8""
MAF with screen: 2"
The Oiled membrane filters will be somewhere
between the paper filters, and nothing. Yeah,
you could gain a whole 1/2" H2O of pressure.
That's like, what, 0.02PSI of boost. Maybe the
intake flows twice as much as my shop vac. Call
it 0.04PSI. Our throttle area is < 2X as big.
On the supercharger price/performance scale,
you're looking at something like $300 per PSI
of boost.
So if the filter costs more than $12, it's more
expensive per lb of boost - incremental horse-
power - than a supercharger.
From what I read, each PSI of boost looks good
for maybe 30 HP. Sanity check this as 325HP stock
HP / 14.7 PSI = 22 HP/PSI.
So using the latter, the ultimate filter [zero
drop] would give you about 22HP/PSI*0.04PSI or
1HP over the better paper ones.
Woo-hoo! Ain't science fun?
I put the Donaldson in a box and run with the
Purolator since that last horsepower isn't
someting I use often and the filter's not
cheap [I dunno if I can even get a replacement].
Re: Which filter with a ram air kit? Thanks, jimmyblue that is exactly what I was looking for. I completely understand what you are saying...I think I'll just stick with the paper filter for now. If I ever have an extra $45 to just throw at the car I'll pick up one of those pretty blue Holley filters.
Re: Which filter with a ram air kit? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by equandt:
<strong>Thanks, jimmyblue that is exactly what I was looking for. I completely understand what you are saying...I think I'll just stick with the paper filter for now. If I ever have an extra $45 to just throw at the car I'll pick up one of those pretty blue Holley filters.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I would reccomend getting a K&N or Holley simply because the FTRA is going to turn your filter black in 2,000 miles. With those cotton-oil filters, you can wash and re-oil them, and good as new. If you stick with the paper filters, you'll be buying new filters on a regular basis.
<strong>Thanks, jimmyblue that is exactly what I was looking for. I completely understand what you are saying...I think I'll just stick with the paper filter for now. If I ever have an extra $45 to just throw at the car I'll pick up one of those pretty blue Holley filters.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I would reccomend getting a K&N or Holley simply because the FTRA is going to turn your filter black in 2,000 miles. With those cotton-oil filters, you can wash and re-oil them, and good as new. If you stick with the paper filters, you'll be buying new filters on a regular basis.
