I like that it uses the factory air box which would save some frustration. It has very good reviews also.

http://www.sporttruckdirect.com/True_Flow.html
http://www.sporttruckdirect.com/Pics...talled_Big.jpg


DODGE INSTALLED VIEW - #30501 Kit.
Note the clean simplicity of design so that all components work with existing factory elements to deliver a very professional underhood appearance. Installed and making added hp & torque in 20 minutes!

When the 5.7L Hemi kit was dyno tested, it made an amazing 19.1 hp and 37.3 ft-lbs of torque!

 

True Flow is trying a large advertising campaign
where they claim to be the 'honest' manufacturer
who emphasizes that they do flow tests of their filters
and that increased cfm flow
will mean increased horsepower.

However, this is deceptive too.

An engine will produce more horsepower
if the pressure drop across the filter goes down.

You can read the actual formula used to predict what the horsepower will do if the pressure changes on page 415 of the Bosch Automotive Handbook 5th ed...which can be read for free online if you get a Gmail account and password.

If the tested flow rate of a filter is higher
it will give a slightly lower pressure drop
but there is a point of
'dimishing returns'
and bigger, bigger, bigger
means less, less and less.

What that means is that you buy a True Flow filter
that measures 1000 cfm
and use it to replace a filter that tests 500 cfm
you won't get twice the horsepower
you might only get 0.1% more horsepower.

On a 2003 5.7 Hemi
the airflow is about 530 cfm at 5400 rpm wide open throttle
where the net shaft horsepower is about 345
if there is no power steering pump
and the engine has been 'broken in' a bit.

The MAP sensor at this rpm and open throttle
is reading within about 0.6 inches Hg of full atmospheric pressure
so there is not a lot of room for improvement
by improving the air flow
of either the throttle body, filter, or air ducts.

In one of their official press releases about the 5.7 Hemi engine
Chrysler bragged that the pressure drop of the entire 5.7 intake system
into the cylinder's combustion chamber was
'less than 10% of atmospheric pressure'

Since the pressure of the atmosphere changes with the weather
but is usually around 30 inches of mercury
that means that the entire combination of
air ducts,
filter,
throttle body,
manifold runners,
cyl head intake port,
and intake valve
creates a total of 3 inches hg of pressure drop.

Since we know the restriction of the air ducts, filter and throttle body
(in front of the MAP sensor)
is about 0.6
that means that the manifold runners, port and valve
create about 2.4 restriction.

This is why race engine builders
concentrate on porting runners and stuffing in bigger valves.
There is more room for real improvements
that result in more horsepower.

 

That is expensive!!! You can buy an Airaid MIT kit (just the tube) for about $100.00 and then buy a drop in filter from K & N for about $65 and have the same set up. Airaid also has the cone filter kit available that uses the botttom of the stock air box and you only have to replace the top piece to be opened. No hassles with this. It just snaps into place over the bottom. This is the set up that I have and it was the same price as your true flow. I would also be a little weary about buying a filter that is color dyed and has print on the actual filter. Common sense would make you think that the ink and dye would restrict air flow in the area.

 

After researching several different CAI systems, I opted for the Airaid CAI for just the reason you mentioned: it uses the bottom of the stock airbox which makes installation a snap (no pun intended! ). Its coming today so unless we get some severe T-storms I will be installing it later this evening.

 

That True Flow intake looks just like my Mopar Liberty Intake. Except I paid $27.00.

 

I would like to check that out (just for reference). Where can I see one at?

 

Deleted by Pappy...It just ain't worth the hassle

Hey man I like your train of thought using the bottom of the stock air box.

 

Look at my gallery. NOW, if you have a 4.7 or 5.7, I dont know if the size of the intake is different from the 3.7. But you can go to dodgeparts and go to the jeep section, then look for the jeep liberty intake 2005.