Airflow Performance FM-200 Air Inlet

I have an IO-360-M1 with Airflow Performance fuel injection (FM-200 controller). Using the smooth lower cowl and firewall forward kit from Vans which has a fiberglass filtered air inlet plenum made for a Bendix fuel injector ? hence flat face mating surface with four bolt holes. Several questions:
1) Has anyone modified the Vans plenum to fit the FM-200 controller? I am aware of several builders who have placed a wye on the FM inlet and used one branch for the filtered air inlet and one branch as ram air inlet. This requires adding a hole in the lower cowl and I?m looking for other solutions.
2) What is the recommended method of attaching inlet plenum to the FM-200 controller?
3) Do you have any attachment pieces that could be used to transition between the fiberglass plenum and the FM-200 inlet?
Photos and/or drawings for the above would be greatly appreciated.

Ron Jagels (RV-8A)

FM200 and air filter

I have the same question - just realized that the Van's snorkel is not going to work with the AFP FM200.

Anyone have a "best and easiest" recommendation for this setup? Thanks!

The least complicated approach is to modify the lower end of the snorkel so it slips onto the FM200, and add a bump/blister to the lower cowl, in front of the FM200, for good clearance.

It's been done before...search is your friend.

Thinking out of the box, assuming your FM200 is new, Don at Airflow might work out a swap deal for an FM150, which is the same length as an RSA-5, and has the same flanges. It will cost you a bit less than 0.5" hg MP.

DanH said:

The least complicated approach is to modify the lower end of the snorkel so it slips onto the FM200, and add a bump/blister to the lower cowl, in front of the FM200, for good clearance.

It's been done before...search is your friend.

Thinking out of the box, assuming your FM200 is new, Don at Airflow might work out a swap deal for an FM150, which is the same length as an RSA-5, and has the same flanges. It will cost you a bit less than 0.5" hg MP.

Click to expand...

Dan is right, modifying the snorkel is easiest. Cowl modification is not required.

Before that with a different engine, I modified the cowl for straight in air flow, with a filter by-pass feature. That worked well but it was a huge amount of work to get to fit together.

Dan Checkoway, an early contributor here, did some testing and found no advantage to straight in by-passed air flow over the snorkel.

The Vans snorkel is well designed and while not perfect, works very well.

Amen on the FM150, that's what I have in the 8. The 7 had FM200.

Split, fit, finger, re-join

I cut mine in half... fit the top and bottom independently, then rejoined them.

At the fuel meter... lop off the flange and lay up the opening for a close slip fit.

At the filter... fit and secure.

The two pieces will not align perfectly but can be adjusted easily by fingering both ends and working the shape a bit with the help of a heat gun ... tape the inside to hold it together... remove and glass and fill the outside... remove tape... glass and fill the inside.

AFP FM200 air filter snorkel

Thanks gents. Looks like I'm going to have to break out the rubber gloves and start playing with the fiberglass.

Or...you can put a scoop on the cowling as I did. Bought the scoop from Rod Bower and integrated an airbox from Spectre Performance. See below:



Fits on the FM200 just fine. Funny thing is that the only other place I've seen this installation was on one of the RVs at the Reno Air Races this year. If you want more detail pics, let me know and I'll get them. I'm going to the airport tonight.

Mark, I'd love to get as many pictures as you have, that would be great!

How hard is it to remove the bottom cowl?

Just looking at your site - seems very clear and very clean. Thanks for the info.

rv8ch said:

Mark, I'd love to get as many pictures as you have, that would be great!

How hard is it to remove the bottom cowl?

Just looking at your site - seems very clear and very clean. Thanks for the info.

Click to expand...

I made the scoop removable which helps a lot...the 3 blade prop is a bigger PITA than the scoop. Still it requires a few carefully aimed expletives to get it all in place.

The air box I used was the Spectre Performance 9833: http://www.spectreperformance.com/search/product.aspx?prod=9833

The best info I could find (and I'm not sure how good this is) says that the filter provides 450 CFM...seems a bit optimistic, but according to the calcs, my engine would require about 289 CFM at 2700 RPM, so I'm thinking I'm ok...that and seeing the same setup on a Reno air racer made me a little more confident that this will be fine. If you use this air box, you'll need to cut it down on both ends, but it will fit perfectly and leave clearance between the air box and the scoop for a rubber duct interface.

I'll send more pics tonight.

I had the very same problem and was wondering how to make the snorkel fit the FM-200 without cutting the lower cowl. I did not find a way without a cutout. I finally exchanged the FM-200 with a FM-150 and the installation was easy because the FM-150 has the same dimensions as the Bendix servo. However the mixture lever was just touching the lower cowl and this without engine sag and movement due vibration or negative G´s. So I ended up making a bump in the lower cowl to clear the mixture lever.

Mark Dickens said:

The air box I used was the Spectre Performance 9833: http://www.spectreperformance.com/search/product.aspx?prod=9833
The best info I could find (and I'm not sure how good this is) says that the filter provides 450 CFM...seems a bit optimistic, but according to the calcs, my engine would require about 289 CFM at 2700 RPM,

Click to expand...

CFM without a pressure loss value means zip. That cone filter doesn't have enough media area for low restriction.

Been there, done that.

http://www.vansairforce.com/community/showpost.php?p=370492&postcount=9

This one did have enough media area. Start at post 11:

http://www.vansairforce.com/community/showthread.php?t=44856&page=2

DanH said:

The least complicated approach is to modify the lower end of the snorkel so it slips onto the FM200, and add a bump/blister to the lower cowl, in front of the FM200, for good clearance.

It's been done before...search is your friend.

Thinking out of the box, assuming your FM200 is new, Don at Airflow might work out a swap deal for an FM150, which is the same length as an RSA-5, and has the same flanges. It will cost you a bit less than 0.5" hg MP.

Click to expand...

Dan, did you mean to say that the switch from FM200 to FM150 would cost 1/2" of MAP? Or did you mean that the snorkel installation through a filter would cost 1/2" of MAP relative to ram air?

Ron,
I just finished mine, AFP200 on an RV8, IO-390. I can't seem to figure out how to post photos, If you PM me with an email address, I will email you photos.
Dick

scsmith said:

Dan, did you mean to say that the switch from FM200 to FM150 would cost 1/2" of MAP? Or did you mean that the snorkel installation through a filter would cost 1/2" of MAP relative to ram air?

Click to expand...

FM200 to FM150, but I spoke hastily, and should clarify.

While researching a Kitplanes article, I asked Don Rivera to run a number of different fuel controllers on the Superflow bench. Here are the numbers, as published:

Airflow was set at 1560 pounds
of air per hour, an approximation of
a 540 Lycoming running 2700 rpm
on a 70?F day at Reno. The numbers
below represent carb loss in inches of
water?the loss of manifold pressure
due to intake restriction. Each control
was fitted with a standard intake bell
mouth before measurement.

RSA-5 12.75 inches
FM-150 10.0 inches
FM-200 4.0 inches
RSA-10 4.9 inches
FM-300A 2.6 inches

So, at 1560 lbs per minute, the difference between an FM150 and an FM200 was 6" H2O, or 0.44132" Hg. That's the hasty part; I didn't recall the flow rate. Obviously the loss would be a bit less with a 360. For our purposes here, lets assume 2/3's of 0.44, or about 0.3" Hg

DanH said:

FM200 to FM150, but I spoke hastily, and should clarify.

While researching a Kitplanes article, I asked Don Rivera to run a number of different fuel controllers on the Superflow bench. Here are the numbers, as published:

Airflow was set at 1560 pounds
of air per hour, an approximation of
a 540 Lycoming running 2700 rpm
on a 70?F day at Reno. The numbers
below represent carb loss in inches of
water?the loss of manifold pressure
due to intake restriction. Each control
was fitted with a standard intake bell
mouth before measurement.

RSA-5 12.75 inches
FM-150 10.0 inches
FM-200 4.0 inches
RSA-10 4.9 inches
FM-300A 2.6 inches

So, at 1560 lbs per minute, the difference between an FM150 and an FM200 was 6" H2O, or 0.44132" Hg. That's the hasty part; I didn't recall the flow rate. Obviously the loss would be a bit less with a 360. For our purposes here, lets assume 2/3's of 0.44, or about 0.3" Hg

Click to expand...

Thanks! this is fantastic data to have. Working with Bob Mills, he has a RSA-5 on his moderately souped up IO-540. This will definitely help him decide what his options are.

scsmith said:

Thanks! this is fantastic data to have. Working with Bob Mills, he has a RSA-5 on his moderately souped up IO-540. This will definitely help him decide what his options are.

Click to expand...

Bob is not a Kitplanes subscriber?

Shame, shame....look what you're missing!

DanH said:

Bob is not a Kitplanes subscriber?

Shame, shame....look what you're missing!

Click to expand...

Bob just needs to juggle less and read more! Steve's pinging me on the side, as I fly people and peanuts from place to place...he always has my back! So the 10.15" delta from RSA-5 to FM-300A equates to about .75" of MP? My old ram air did that, and it was consistently worth 3 mph (multiple tests and races showed it, and that matches the rule of thumb I was taught...1" MP = 4 mph...YMMV). The follow-on James inlet produced similar results, even filtered, likely attributable to better cowl inlet shape (thanks Steve!). I've had my eye on the FM-300 for a while...now that the engine is off for a mount repair, I may not have an excuse left. May try an internal plenum experiment to see if I can better the .75". One friend said I couldn't add horsepower via a mount change, and I said "watch me". Guess I better step up!

Steve and I were looking at the AFP site and trying to verify that the 300A is the non-purge valve version. Is that correct Dan?

Thx...great info as always!

Cheers,
Bob

DanH said:

FM200 to FM150, but I spoke hastily, and should clarify.

While researching a Kitplanes article, I asked Don Rivera to run a number of different fuel controllers on the Superflow bench. Here are the numbers, as published:

Airflow was set at 1560 pounds
of air per hour, an approximation of
a 540 Lycoming running 2700 rpm
on a 70?F day at Reno. The numbers
below represent carb loss in inches of
water?the loss of manifold pressure
due to intake restriction. Each control
was fitted with a standard intake bell
mouth before measurement.

RSA-5 12.75 inches
FM-150 10.0 inches
FM-200 4.0 inches
RSA-10 4.9 inches
FM-300A 2.6 inches

So, at 1560 lbs per minute, the difference between an FM150 and an FM200 was 6" H2O, or 0.44132" Hg. That's the hasty part; I didn't recall the flow rate. Obviously the loss would be a bit less with a 360. For our purposes here, lets assume 2/3's of 0.44, or about 0.3" Hg

Click to expand...

Pressure squares with flow so if you reduce the flow by 2/3 (66%), the delta pressure will change to the square of the amount changed.

So while the flow between the two engines is assumed to change by 66% the pressure drop between the 2 engines would be 43% resulting in ~2.6136" H2O or 0.1922" Hg.

rvmills said:

So the 10.15" delta from RSA-5 to FM-300A equates to about .75" of MP?

Click to expand...

Yes, approximately.

May try an internal plenum experiment to see if I can better the .75".

Click to expand...

...which will vary with altitude, temperature and velocity, so be sure to compare apples. If we assume 5150 (Stead +100) altitude, 70F local, normal baro, and 230 KTAS, available Q would be 2.05" Hg. Yes, there is some room for improvement.

Is 230 about right, and how many RPM?

Steve and I were looking at the AFP site and trying to verify that the 300A is the non-purge valve version. Is that correct Dan?

Click to expand...

Ask Don. I suspect you can have it either way, drum or disk mixture valve. Disk valve units have a lower leak rate in idle cutoff, thus in theory don't need a purge valve...the real purpose of which is to bleed drum valve leakage back to a tank rather than into the engine.

rvmills said:

So the 10.15" delta from RSA-5 to FM-300A equates to about .75" of MP?

Click to expand...

Negative. If you assume the reduced flow from a 540 (where the test data was collected) to the 360. You have 66% of the air flow. At 66% of the air flow the pressure drop through the fuel controller will be 43.6% so the pressure differential from the RSA-5 to the FM-300A when installed on a 360 running at 2700RPM is 4.4356 inches w.c. or ~ 0.325 inches Hg.

EDIT: OH! hey Bob. Nevermind. Yes .75" Hg. is correct for your application. I didn't think about you running a 540 :grin:

SuperCubDriver said:

I had the very same problem and was wondering how to make the snorkel fit the FM-200 without cutting the lower cowl. I did not find a way without a cutout. I finally exchanged the FM-200 with a FM-150 and the installation was easy because the FM-150 has the same dimensions as the Bendix servo. However the mixture lever was just touching the lower cowl and this without engine sag and movement due vibration or negative G?s. So I ended up making a bump in the lower cowl to clear the mixture lever.

Click to expand...

I'm having to do the same on my -7A with FM-150 and Jame's cowl. Otherwise, a great fit.

DanH said:

Yes, approximately.

Click to expand...

Thanks!

DanH said:

...which will vary with altitude, temperature and velocity, so be sure to compare apples. If we assume 5150 (Stead +100) altitude, 70F local, normal baro, and 230 KTAS, available Q would be 2.05" Hg. Yes, there is some room for improvement.

Is 230 about right, and how many RPM?

Click to expand...

Getting close. 230 is the next threshold. Last full speed 4-way test hop was 258 mph, and the qualifying speed that year (2 years ago) was 257, so good correlation. That's about 224 KTAS, so we're in the ball park. 2700-2780 seems to be the sweet spot...fine tuning that gets into the hard to measure range...still tweaking! Call it 2750 for calcs. Your estimate is probably within the second place after the decimal!

The plenum/velocity stack experiment is one that a fellow racer in a Lancair 360 conducted (Tom, who also posts here). He added an AFP servo and his plenum/v-stack, and gained MP. However, he did them together, and he concurred that he can't make attribution of the gains to one part of the change or the other. Here's the mold for my version, and the v-stack I laid up with Tom's design as a baseline.







The v-stack goes inside the plenum, and both attach to the servo inlet. Of course that v-stack is sized for the RSA-5, so I'll need to make another if I spring for the FM-300.

Steve is doubtful that the plenum did much, but the experiment beckons. Its been slow-rolled due flying other race aircraft and our wing project...and I need to focus on spar stubs, so a step by step approach to the quest for MP is probably a likelihood. Like I said...juggling a bit!

DanH said:

Ask Don. I suspect you can have it either way, drum or disk mixture valve. Disk valve units have a lower leak rate in idle cutoff, thus in theory don't need a purge valve...the real purpose of which is to bleed drum valve leakage back to a tank rather than into the engine.

Click to expand...

Will do...need to get smarter about the disk/drum differences, and the operational characteristics of each. Currently have a sniffle valve.

Thanks for the great feedback!

Weasel said:

Negative. If you assume the reduced flow from a 540 (where the test data was collected) to the 360. You have 66% of the air flow. At 66% of the air flow the pressure drop through the fuel controller will be 43.6% so the pressure differential from the RSA-5 to the FM-300A when installed on a 360 running at 2700RPM is 4.4356 inches w.c. or ~ 0.325 inches Hg.

EDIT: OH! hey Bob. Nevermind. Yes .75" Hg. is correct for your application. I didn't think about you running a 540 :grin:

Click to expand...

Thanks...appreciate the six cover though! Kinda cheatin' with this motor!

Cheers,
Bob