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IO-390 Question (Airflow Performance Fuel Injection)

Reflex

Well Known Member
Recently I ordered the IO-390 for my -14. After speaking with Tech, I chose the Airflow Performance Fuel Injection option at no charge.

Yesterday, I got an e-mail from Van's wanting to make sure that I really wanted the Airflow system as it is difficult to fit in the cowl. This is the first I've heard of this potential issue.

Just wondering what the rest of you are doing with regard to Avstar vs. Airflow on the RV-14?

Fred
 
There are several posts on AFP on an RV-14 IO-390 engine so recommend a quick search. If memory serves you will need to modify the snorkel, but most important is you need to give Dan at AFP a call as he has a tailored control linkage kit for this engine.

Side note - I ordered my RV-8 IO-360-M1B from Thunderbolt (Lycoming) with the AFP injection. After many frustration attempts I determined that it would simply not fit without major cowl modification. The good folks at Thunderbolt exchanged the system for the standard Precision unit at no cost. I would however had preferred the AFP system.

Carl
 
Depends on the choice of FM-150 or FM-200.

The 150 has a flanged inlet and mimics the physical dimensions of an AvStar or Bendix RSA-5, thus there should not be cowl or snorkel issues.

The 200 is larger, and has no intake flange, just a round tube shape requiring a clamped connection. The extra length can require a cowl mod, and the flanged Vans snorkel would need modification if it's your choice of intake filtration.

The linkage kit is apparently required with the FM150, but that's not a cowl issue.

Photos: https://www.danhorton.net/Articles/Bendix-and-Beyond (1).pdf

Carl, I'm curious...your fit issue was FM150 or FM-200? I'm flying an FM200 on an 8, same horizontal sump.
 
For the FM-150 in the RV14 you need the throttle and mixture control adapter kit that allows you to use the stock cables with the FM-150 and also has the spacer required for the Fm-150 to fit the sump without hitting the throttle mechanism. Those are simple bolt in mods (probably simpler than the stock bellcrank mixture arm deal). You also have to modify the snorkel slightly since the Fm-150 is now farther out from the sump than the Avistar stock servo. There is a long thread on VAF on how to do it - not difficult, just a mod that needs to be made. There are zero mods needed to the cowling itself.

PS- very happy with the Airflow Performance system and the service from them on my 14A
 
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SNIP

Carl, I'm curious...your fit issue was FM150 or FM-200? I'm flying an FM200 on an 8, same horizontal sump.

FM-150.
I tried every orientation, talked to Don at AFP as well as Thunderbolt. The lower cowl curves up too fast. I found one way to do it but this would require modifying the control linkages, the fuel ports as well as the snorkel. At that point I decided my desire for the AFP system was outweighed by the added work to make it happen.

It turns out I was not the first person to find this out as several other RV-8 builders had to exchange the AFP system for the stock Precision unit. Talking with Van?s they also made it clear they were discussing the issue with Thunderbolt as well.

That said, I would not hesitate to install the FM150 on an RV-14(A) IO-390.

Carl
 
Gentlemen,

Many thanks for your replies. I took your advice and contacted Don. He told me exactly what the three of you posted. I am moving forward with APF.

Thanks again,

Fred
 
I got the FM150 not knowing the difference. It was recommended by the Lycoming Thunderbolt rep. Of course I needed the linkage kit. And a hose was different from the red cube forward as I recall. And the snorkel had to be adjusted which was a learning opportunity but not really hard. Later on I found it matters how the mixture control cable is bolted because nut down the nut hit the cowling enough to start rubbing a hole.

I also have a whole bag of parts that the stock throttle used to attach the mixture cable that I didn?t need.

I don?t know if the fm150 is better. But it works well and my install looks great. The stock throttle is probably less hassle.
 
I ordered FM-150 with my Thunderbolt IO-390 and used the airflow mounting plate for throttle/mixture cables. No problems with cowling, but did have to modify the snorkel to fit - easy but a bit time consuming.

I ordered my hoses from TS Flightlines - they are familiar with this setup, no big deal at all.
 
Very timely string as I as scratching my head how I was going to make this work. I’ll order the kit, can someone point me to the modifications required for the snorkel?
 
The snorkel is something you just figure out. It comes in an upper and a lower half. I cut out the four corners in lower part of the upper half - like making long slots. That freed the sides to be moved so they would slide into the box of the lower half. The fore and aft sides moved forward a bit. The right and left sides I trimmed like a trapezoid. Trimmed and fit then glassed the assembly in place. Finished with flox and fabric to make it all smooth.

A few people here modified at the bottom of the lower half at the intake. That shape seemed too difficult for me. There are good pics in other threads showing either approach. It really wasn?t hard after I just went ahead and chopped up the top section.

Some have had the snorkel end up too high at the baffling. Mine was about 1/8 too high but now that the engine has settled it is just right.
 
At that point I decided my desire for the AFP system was outweighed by the added work to make it happen.

It turns out I was not the first person to find this out as several other RV-8 builders had to exchange the AFP system for the stock Precision unit. Talking with Van?s they also made it clear they were discussing the issue with Thunderbolt as well.

There lies the challenge for the EAB vendors. The market has been greatly expanded by the availability of kits and packages which require only assembly, with little fabrication. The larger marketplace is good for everyone.

The flip side is a growing notion that there is something "wrong" when things don't just bolt together, or that fabrication is an unjustified burden.
 
AFP FM200 Installation

Depends on the choice of FM-150 or FM-200.

The 150 has a flanged inlet and mimics the physical dimensions of an AvStar or Bendix RSA-5, thus there should not be cowl or snorkel issues.

The 200 is larger, and has no intake flange, just a round tube shape requiring a clamped connection. The extra length can require a cowl mod, and the flanged Vans snorkel would need modification if it's your choice of intake filtration.

The linkage kit is apparently required with the FM150, but that's not a cowl issue.
snipped
Carl, I'm curious...your fit issue was FM150 or FM-200? I'm flying an FM200 on an 8, same horizontal sump.

Dan,
As I also have an FM200, I'd like your thoughts/comments regarding it's fit and operation on your engine. How does your air filter housing interface with the cowl? I found some photos in your "Frankensnorkel" folder. None of them deal with the cowl interface.
 
Dan,
As I also have an FM200, I'd like your thoughts/comments regarding it's fit and operation on your engine. How does your air filter housing interface with the cowl? I found some photos in your "Frankensnorkel" folder. None of them deal with the cowl interface.

I don't think the FM-150 existed when I bought the 390, so it was the FM-200 or an RSA-5 type. I wanted Airflow Performance, not Precision.

The FM-200 may not make any additional power on a 360/390, as compared to an FM-150. The intake restriction is probably the inlet flange on the sump plenum, smaller than the FM 200's throat diameter, and requiring an adapter. Regardless, it runs fine.

The unit is installed with the mixture and throttle levers on the bottom. I welded up a cable bracket which bolts to the bottom of the sump.

As noted, the FM-200 is longer than the Bendix-style units, so a snorkel was never in my plans. That was ok, as I was going to revise the cowl anyway.

http://www.vansairforce.com/community/showpost.php?p=311505&postcount=1

http://www.vansairforce.com/community/showpost.php?p=362947&postcount=11

http://www.vansairforce.com/community/showpost.php?p=362952&postcount=13

http://www.vansairforce.com/community/showpost.php?p=364799&postcount=15

http://www.vansairforce.com/community/showpost.php?p=372665&postcount=19
 
AFP FM200 Installation

snipped The intake restriction is probably the inlet flange on the sump plenum, smaller than the FM 200's throat diameter, and requiring an adapter. Regardless, it runs fine.

The unit is installed with the mixture and throttle levers on the bottom. I welded up a cable bracket which bolts to the bottom of the sump.snipped

Yes, I have that adapter. Were you able to use the stock throttle & mixture cables supplied by Vans? If not, what length cables did you use? I like your cable heat shield, well done! How is the plastic outer covering doing? Does the heat shield protect them well?

Do you know what main jet is in your FM200?
 
Yes, I have that adapter. Were you able to use the stock throttle & mixture cables supplied by Vans? If not, what length cables did you use? I like your cable heat shield, well done! How is the plastic outer covering doing? Does the heat shield protect them well?

Do you know what main jet is in your FM200?

Cables...hmm, I've slept since then. The green ones for sure. Probably stock length, as I made an extension for one of them.

Same cables, 870 hours now.

Whatever jets Don or Kyle put in there circa 2007. Spot on.
 
FM200 Updated air box design??

I don't think the FM-150 existed when I bought the 390, so it was the FM-200 or an RSA-5 type. I wanted Airflow Performance, not Precision.

The FM-200 may not make any additional power on a 360/390, as compared to an FM-150. The intake restriction is probably the inlet flange on the sump plenum, smaller than the FM 200's throat diameter, and requiring an adapter. Regardless, it runs fine.

The unit is installed with the mixture and throttle levers on the bottom. I welded up a cable bracket which bolts to the bottom of the sump.

As noted, the FM-200 is longer than the Bendix-style units, so a snorkel was never in my plans. That was ok, as I was going to revise the cowl anyway.

http://www.vansairforce.com/community/showpost.php?p=311505&postcount=1

http://www.vansairforce.com/community/showpost.php?p=362947&postcount=11

http://www.vansairforce.com/community/showpost.php?p=362952&postcount=13

http://www.vansairforce.com/community/showpost.php?p=364799&postcount=15

http://www.vansairforce.com/community/showpost.php?p=372665&postcount=19

Is this the Mk II air filter design? It doesn't look like the filter setup in your "Frankensnorkel" folder. Photos linked below

https://www.danhorton.net/VAF/Frankensnorkle/PA120002.JPG

https://www.danhorton.net/VAF/Frankensnorkle/PA120003.JPG

https://www.danhorton.net/VAF/Frankensnorkle/PA120005.JPG

Was the pressure drop with the design above unsatisfactory? Why the change? My search of K & N didn't turn up a part number for BD20A4.
 
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When checked on the flow bench at AFP, the cone filter was too restrictive. Don suggested I try to design something with a deep pleat flat filter. I did, and it flowed very well.
 
I purchased the stock IO390 sold by Van's, and the AvStar that Lycoming recommended in 2018 for the 14A. The Van's RV14 build drawings, photos and firewall foreword parts all fit perfect without mods. After 140 hours, this IO390 with stock Slick Mags is the smoothest running Lycoming I have ever owned.
 
I purchased the stock IO390 sold by Van's, and the AvStar that Lycoming recommended in 2018 for the 14A. The Van's RV14 build drawings, photos and firewall foreword parts all fit perfect without mods. After 140 hours, this IO390 with stock Slick Mags is the smoothest running Lycoming I have ever owned.

As always, an RV flies fine with a stock engine choice.
 
Great article Dan!

Depends on the choice of FM-150 or FM-200.

The 150 has a flanged inlet and mimics the physical dimensions of an AvStar or Bendix RSA-5, thus there should not be cowl or snorkel issues.

The 200 is larger, and has no intake flange, just a round tube shape requiring a clamped connection. The extra length can require a cowl mod, and the flanged Vans snorkel would need modification if it's your choice of intake filtration.

The linkage kit is apparently required with the FM150, but that's not a cowl issue.

Photos: https://www.danhorton.net/Articles/Bendix-and-Beyond (1).pdf

Carl, I'm curious...your fit issue was FM150 or FM-200? I'm flying an FM200 on an 8, same horizontal sump.

Dan,
Great write up. Your article in Kitplanes really lays out the advantages of the Airflow Performance Servo. I started reading the article a few days ago, but did not have time to finish it till last night. For all others following this thread, I recommend you read Dan's article linked above.

Dan, are you still using the drum style mixture valve in your FM200? Or did you upgrade it to the FM200A spec?

Per AFP, the FM150 is 5.5" long, same as an RSA5. I dug out my FM200 [which I had just packed away in 2" of bubble wrap 2 days prior] to measure it. Length from throat to base flange is 6.12". My adapter adds 1 3/16" to that.

I'm going to have to remove my sump to see if there is any way to weld up and relocate the servo mounting stud holes. That would eliminate the adapter. The sump throat would also have to be opened up or tapered.

Charlie
 
Dan, are you still using the drum style mixture valve in your FM200? Or did you upgrade it to the FM200A spec?

Mine is the simple drum. Works fine, but as a practical matter, requires the purge valve for clean idle cut-off.

I'm going to have to remove my sump to see if there is any way to weld up and relocate the servo mounting stud holes. That would eliminate the adapter. The sump throat would also have to be opened up or tapered.

Before going to the trouble, I'd set up a flow bench check to determine the plenum inlet restriction (or lack thereof). The easiest way to do it would be to simply machine two faux inlets in a flat aluminum plate. One would duplicate the inlet hole in the sump plenum, complete with adapter. The other would be the enlarged, no-adapter hole. Set the plate on a box or tube, something to sit over the flow bench inlet. Talk to Don for detail. I'll bet he would cheerfully run it on his Superflow.

In the not too distant future I'll be measuring inlet air temperature just short of the intake port, for comparison with OAT. Already have some injector bleed deltaP and port pressure wave measurements.

As for welding the existing stud holes, consider rotating the FM200 a bit. A bit out of the box, but no law says it must be mount on cardinal points.
 
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A question for the moderators

Since this thread is really more about fuel injection than building an RV 14 would it perhaps be better if this thread was moved into the fuel injection section?

Charlie
 
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