IO-390 Question (Airflow Performance Fuel Injection)

Reflex · #1 08-02-2019, 07:57 AM

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

Carl Froehlich · #2 08-02-2019, 08:07 AM

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

DanH · #3 08-02-2019, 08:32 AM

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/B...yond%20(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.

Nova RV · #4 08-02-2019, 08:44 AM

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

Carl Froehlich · #5 08-02-2019, 08:56 AM

Quote:

Originally Posted by DanH

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

Reflex · #6 08-02-2019, 10:20 AM

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

JDA_BTR · #7 08-02-2019, 02:59 PM

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.

mturnerb · #8 08-02-2019, 07:10 PM

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.

Cwood2000 · #9 08-02-2019, 08:13 PM

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?

JDA_BTR · #10 08-02-2019, 09:02 PM

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.