The work that the air pump has to do is based on restriction and flow.

You are going wrong in doubling the restriction since air is being pulled in at that restriction on each side.

Velocity and turbulence play a factor as well in arriving at restriction.

 

If you got more insight ,I'd love to hear it. To me it seems as a simple calculation ,two tubes at .6 psi on each side x2. Someone with good physics skills is needed here

 

I already am, but my explanations were disregarded.

 

I didn't see an explanation I only seen your calculation that .6 plus .6 is still .6. did I miss something else ?

 

Flow loss in any dual ducting is a binary factor. Any additional ducting would create an average restriction, not a cumulative. How could more flow create a higher obstruction?
Take my word for it, airflow restriction in any poly configuration amasses to an average. In your previous example, .6 drop on one side and a .6 drop on the other side would be a total of .6 drop for both. The average of .6 and .6 IS .6.
Follow this....... if there was a 10% drop on one of two sides and a TOTAL blockage on the other side, there would NOT be a combined loss of 100% + 10%. It would be half of the total @ 55%. Average. Not accumulation.

 

I didn't see an explanation I only seen your calculation that .6 plus .6 is still .6. did I miss something else ?

 

Somehow I think the engineers at Jaguar were smart enough to size the filters for these cars. Does the XKR-S and the GT use the same filter set up.

 

Think of it like two electrical wires.

If you measure 1 ohm resistance on each wire; the resistance for both of the wires together is still 1 ohm.

The resistance you measure on each path is an average not a total - because air is flowing at that resistance.

If you have three wires with 1 ohm resistance, the resistance is still 1 ohm.

 

And apparently Mercedes engineers we're thinking that a 350hp e55 AMG needed an air filter 35% larger than 416h or 510hp in 5.0 xkr. Engineers are human after all, and there are different factors such as cost, time and so on they they follow by to get things done.

 

If we are to follow this logic it would make no difference on where the restriction is measured in the intake tube, but it does make a difference . If I measured the restriction at near the throttle body restriction would not be at .6 but much higher, the higher you go up the streem the higher restriction gets because it's cumulative and not an average. Two streams of air from both tubes will meet up and create higher velocity and flow volume and thus more restriction. By calculations In my head there is no way that it will be .6 by the throttle body vs on one side of the intake . Would love to be proven wrong though ...

 

I would assume the 349 HP is a NA fed engine where the addition area would be needed. Don't know the dynamics here but would believe the engineers picked the optimum needs considering the performance criteria they were aiming for. Bigger isn't necessarily better.

 

The Merc is probably just designed for higher capacity. I.e. longer service interval or more extreme use, such as Saudi desserts.

 

They probably have similar filter surface area, so similar life at a given air flow. The Jag has many more pleats than the Merc, so probably similar filter area. The main difference is velocity through the filter, the Merc air face velocity is lower than the Jag at the same air flow rate. Higher velocity translates into higher pressure drop, so the Jag would need a deeper vacuum to draw the same air flow as the Merc.

 

In the original photo and post this is a k&n filter for the e55 but the stock looks to have the same amount of pleats and about 35% more area compared to xkr, plus the Mercedes air filter sits right on top of the throttle body with minimum restriction compared to the longest intake tubes that I've ever seen on our xkr's ,Go figure
Below is e55 OEM filter

 

Naw, that's not a K&N filter, they don't use paper. You posted a K&N picture in the first comment in this thread.
Below are the K&N filters for an XK:

 

Cee Jay, he is talking about his comparison photo.

 

I would use BMCs: https://www.bmcairfilters.com/eng/ca...55-20/1228/art

 

His post was edited/corrected. He probably just loaded the wrong pic by accident. I've done that also.