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[Midnight Rider]

[smiley=confused5.gif]   This is a nice looking air cleaner, but one thing about this has me slightly confused.  They claim a 15% increase in air flow, but no remapping is required (not talking about closed loop systems either).  Let me see, same amount of fuel, 15% more air, but A/F remains the same.  Maybe in some parallel universe, but not where I'm sitting. [smiley=nixweiss.gif]

Jerry

Jerry, you are certainly light years ahead of me on this subject, so I have a question...is the ECM able (with a PCIII or SERT) to compensate at all for small changes in air flow, or other conditions.  I've got a handle on how the things work, but not all of the nuances of it's adaptability, or ability to compensate for changes in air density, etc.

[grc]

Terry,

One big difference between the H-D EFI and the one on our cars and trucks is a mass airflow sensor.  Cars and trucks have them, and H-D does not.  If our bikes did have one, then it would make the EFI capable of adjusting to actual airflow (stock filter / dirty filter / low restriction filter / etc.).  As it is, all we have is a MAP (manifold absolute pressure) sensor and IAT (intake air temp) sensor to help approximate air density.  (And, in their infinite wisdom H-D chose to locate the IAT sensor in the throttle body, where it picks up heat from the heads and tells the ECM to lean out the mixture, which makes the engine run even hotter.)

Jerry

[Midnight Rider]

Terry,

One big difference between the H-D EFI and the one on our cars and trucks is a mass airflow sensor.  Cars and trucks have them, and H-D does not.  If our bikes did have one, then it would make the EFI capable of adjusting to actual airflow (stock filter / dirty filter / low restriction filter / etc.).  As it is, all we have is a MAP (manifold absolute pressure) sensor and IAT (intake air temp) sensor to help approximate air density.  (And, in their infinite wisdom H-D chose to locate the IAT sensor in the throttle body, where it picks up heat from the heads and tells the ECM to lean out the mixture, which makes the engine run even hotter.)

Jerry

Jerry...thanks for that explanation, and I understand that on the pre '07 bikes (other than the 06 Dyna) there was no real feedback "loop" from any sensors so that things will adjust themselves...no closed loop whatsoever.  One thing I would like 'splained to me (I have a thought on this, but would like another opinion) is I'm looking at two Dyno pulls on a bike with a PCIII...on one pull the engine (SE A/C (K&N)) is showing 92tq/90hp and A/F at WOT of 13:1 - 13.4:1.  Next run the A/C is removed and replaced with a slightly higher flow unit, much like the Doherty...95tq/94hp (I'm rounding to the nearest whole number), but the A/F is now running at WOT 12.8:1 - 13.2:1, so it got richer.  My armchair explanation for this is that because more air is moving through the intake, the sensor might be cooler, and the MAP would change as well, so it let's more fuel in.  Am I way off base here?  And if the mix becomes richer with more air flow through the manifold because of a different A/C, but same pipes, is there a reason to be concerned as long as it all stays within reasonable parameters?  Reasonable being 12.8 to 13.6, definitely never getting over 14:1.  I know you don't want the thing going all over the place in A/F ratio, but if it's staying within .2 of a target ratio (either side), is this acceptable tuning?  Obviously, something is telling the ECM that the motor needs more fuel in this particular case.

What's going on?  What role is the PCIII playing in the above mentioned situation?

[ESJ JESTER]

I wonder on that one Terry if the tps switch could have been deciding factor. i dont  believe the air temps sensivity is as factorable as that of a air density/mass air flow sensor. The platinum wire heated to 1400 deg in a mass air flow indeed can "sense" the air flow as it's "temperature" directly changes with volume flow and thus adjusts the pulse width(open time) of the injector.  I wonder actually  what the refresh rate of the ecm is?  I would think map/tps might be the primary factors involved??     Just wondering along with ya [smiley=nixweiss.gif]
Gene

[grc]

Terry,

The MAP and IAT sensors are used to approximate air flow, so the result you saw on the dyno with the two different flow rate air cleaners is understandable.  My point was that this is a rather imprecise method versus direct measurement of flow with a mass airflow sensor, especially with the location H-D uses for the IAT sensor.  After paying a bunch of bucks for a precise dyno tune, do you really want a +/- 0.3 or 0.5 on your A/F?

The following is the formula used to approximate flow with a MAP/IAT system:
Mass Airflow Rate [ch8776] RPM × (MAP / TEMP)

As for the PCIII, it only adds or subtracts a percentage of fuel (based on the map, throttle position versus rpm) to the amount previously calculated by the ECM.  It would not have caused the affect you noticed.

Jerry

[Midnight Rider]

dyno run...

[Midnight Rider]

Terry,

The MAP and IAT sensors are used to approximate air flow, so the result you saw on the dyno with the two different flow rate air cleaners is understandable.  My point was that this is a rather imprecise method versus direct measurement of flow with a mass airflow sensor, especially with the location H-D uses for the IAT sensor.  After paying a bunch of bucks for a precise dyno tune, do you really want a +/- 0.3 or 0.5 on your A/F?

The following is the formula used to approximate flow with a MAP/IAT system:
Mass Airflow Rate [ch8776] RPM × (MAP / TEMP)

As for the PCIII, it only adds or subtracts a percentage of fuel (based on the map, throttle position versus rpm) to the amount previously calculated by the ECM.  It would not have caused the affect you noticed.

Jerry

Thanks again, Jerry...the experience I have with air flow/temp measuring all comes from the HVAC industry, and particularly measuring lab hood/stack velocity to ensure a negative pressure differencial regardless of hood opening position, and differences in pressure for "clean" rooms in bone marrow transplant units, so I understand the principles, but not the specifics of adding fuel to that whole scenario.  Appreciate the explanation!

[Midnight Rider]

Received my Doherty Powerpacc yesterday...it was delayed (ordered last Tuesday, the 9th) as they were waiting on a couple of parts to come in.  Overall impressions just pulling it out of the box and checking all the parts...VERY well made, good clean machine work, quality pieces.  All the aluminum is polished to a high sheen, so it looks chrome.  The backplate is a machined piece, not stamped, and the venturi is a highly polished, close tolerance (the way it fits into the backplate) fit, with an O ring to seal the venturi against the backplate.

103...the filter oil is BLUE!!

The filter itself is a bit wider than the 800 K&N (will stick out slightly further)  I'll take some pics tomorrow when I install everything, and you can judge for yourself.  The way the backplate and filter mount is different, and looks to be a better design than the stock, or the SE piece.  

[Chief]

Received my Doherty Powerpacc yesterday...it was delayed (ordered last Tuesday, the 9th) as they were waiting on a couple of parts to come in.  Overall impressions just pulling it out of the box and checking all the parts...VERY well made, good clean machine work, quality pieces.  All the aluminum is polished to a high sheen, so it looks chrome.  The backplate is a machined piece, not stamped, and the venturi is a highly polished, close tolerance (the way it fits into the backplate) fit, with an O ring to seal the venturi against the backplate.

103...the filter oil is BLUE!!

The filter itself is a bit wider than the 800 K&N (will stick out slightly further)  I'll take some pics tomorrow when I install everything, and you can judge for yourself.  [highlight]The way the backplate and filter mount is different, and looks to be a better design than the stock, or the SE piece.[/highlight]  

How can that be?

Very interested in hearing your impressions. Would have been more interested if I hadn't just received and mounted my own Roll your own, but still interested.

Chief

[Midnight Rider]

How can that be?

Very interested in hearing your impressions. Would have been more interested if I hadn't just received and mounted my own Roll your own, but still interested.

Chief

Chief...I'll be putting in on tomorrow, but looking at the directions, they don't use the same kind of bolt configuration for holding the filter on...I can't remember what the bolts are called, but on the SE unit there are three bolts that go through the backplate and screw into the TB...those bolts have threads in the end to hold on the filter, so you've basically got a pretty good bit of stress on those three bolts going into the TB with the weight of the filter and cover basically "hanging" off something threaded into the TB...I've had two of them break off in the TB on me (probably overtightened by tech at dealer), and almost lost my entire filter and cover...it was hanging by one bolt, and it happened all of a sudden too.  I know there is a better bolt out there from Zippers (and probably elsewhere).  Fortunately, that happened to me on the way to the tuner for my PCIII, so we were able to fix it in his shop, but one of the bolts had broken off in the TB with no "tit" to get a pair of vice grips on to get it out, so had to drill out (very carefully, I might add... [smiley=nervous.gif])...no harm was done, but it took a few minutes.  Must be very careful not to overtighten those three bolts!!!!

The machined backplate on the Doherty appears to be held on in two places...the "banjo" type bolts that go into the heads which provide the breathing (which hold on the PowerVents), and then three short bolts which bolt the plate directly onto the TB, then the Venturi gets stuck in the mouth of the backplate/TB...the filter gets held on my three seperate bolts that screw into the machined backplate, through a top plate for the filter, then the center hole for the cover, per normal.

Really appears to be a "better mousetrap"...I'll take some pics when I install tomorrow and post them so you'll see what I'm talking about and pass your own judgement.  What I"m impressed by most though is the machine work on the backplate and Venturi...really well made stuff.  The way it's going to make the air flow into the mouth of the TB has got to be better to some extent...not making any claims as to how much power difference that will make, but it is definitely a nice transition for the air to move through the filter and into the mouth...

[Chief]

Chief...I'll be putting in on tomorrow, but looking at the directions, they don't use the same kind of bolt configuration for holding the filter on...I can't remember what the bolts are called, but on the SE unit there are three bolts that go through the backplate and screw into the TB...those bolts have threads in the end to hold on the filter, so you've basically got a pretty good bit of stress on those three bolts going into the TB with the weight of the filter and cover basically "hanging" off something threaded into the TB...I've had two of them break off in the TB on me (probably overtightened by tech at dealer), and almost lost my entire filter and cover...it was hanging by one bolt, and it happened all of a sudden too.  I know there is a better bolt out there from Zippers (and probably elsewhere).  Fortunately, that happened to me on the way to the tuner for my PCIII, so we were able to fix it in his shop, but one of the bolts had broken off in the TB with no "tit" to get a pair of vice grips on to get it out, so had to drill out (very carefully, I might add... [smiley=nervous.gif])...no harm was done, but it took a few minutes.  Must be very careful not to overtighten those three bolts!!!!

The machined backplate on the Doherty appears to be held on in two places...the "banjo" type bolts that go into the heads which provide the breathing (which hold on the PowerVents), and then three short bolts which bolt the plate directly onto the TB, then the Venturi gets stuck in the mouth of the backplate/TB...the filter gets held on my three seperate bolts that screw into the machined backplate, through a top plate for the filter, then the center hole for the cover, per normal.

Really appears to be a "better mousetrap"...I'll take some pics when I install tomorrow and post them so you'll see what I'm talking about and pass your own judgement.  What I"m impressed by most though is the machine work on the backplate and Venturi...really well made stuff.  The way it's going to make the air flow into the mouth of the TB has got to be better to some extent...not making any claims as to how much power difference that will make, but it is definitely a nice transition for the air to move through the filter and into the mouth...

I need to work on my sarcasm. Evidently it wasn't apparent enough. I should have said... What? Someone manufactured something better than the piece of finely engineered and manufactured piece of craftmanship that Harley sells? I find that hard to believe.

That would have worked better.

Chief

[Midnight Rider]

Installed the Doherty PowerPacc today...fairly straightforward, and easy to do.  Here's some pics of the process...did not get a chance to ride today as I have the fairing off for some other work, and it won't go back on until sometime next week, so I'll have to give the seat of the pants report later.  Over all impressions: the machine work on the parts is very nice...all parts and pieces are quality made...instructions are easy to follow.  The PowerPacc vents are one way "valves" which allow pressure in the crankcase to vent either to the atmosphere, or into the inside of the filter mount, but do not allow air to be sucked back in on the downstroke of the piston.

The pics will show how it works..

First pic is of all the parts and pieces that come with the kit...

[Midnight Rider]

This is a pic of the filter backplate, which is machined out of a solid piece of aluminum, then polished.  You can see how it mounts differently to the TB...the studs for the filter mount came already in place..again, machined pieces which do not screw into the TB, but into the backplate as shown...

[Midnight Rider]

This is a pic of the PowerPacc vents, or one way "valves", O ring for sealing the venturi to the backplate...

[Midnight Rider]

Off with the old backplate....you can see the bolts which hold the filter on also thread into the TB, and the old vents bolted into the heads, which also hold the backplate on...