R

Redwagon

Active Member
So the engine shop has come back to me with a great question re the IO360M1B destined for my RV8. They are giving me a choice between the Bendix/Precision Airmotive RSA-5 (or silverhawk experimental version) and the Airflow performance FM200. This large & well known shop actually prefers the Silverhawk and feels more comfortable with that over the FM200, but has indicated that there is less pressure loss (more HP) from the FM200 and they'll go that route if I prefer. (as a funny aside, they have all their FI servos rebuilt by AFP anyway)

I've talked to Don at Airflow Performance (very helpful!) and have seen some of his posts here. Looks like the downside of the AFP system is that its 3/4" longer out the front and not as many shops are familiar with it. There is also the purge valve return line to install, but thats not a big deal.

So of course I want more MP at altitude (the throttle body on the AFP is 3 1/16" vs 2 5/16" on the PA Silverhawk), but a little voice in me likes the conservative bendix standard. So there I'm stranded. :)

I'm planning on using the Rod Bower ram air induction, not sure if that 3/4" extra length will cause me grief as I'm a ways away from cowl work etc.

Looking to the group here for input/comments and reasoning on one versus the other......

Tim
 
Silverhawk Servo

Go with the Silverhawk. I just installed one I bought from Aircraft Spruce on my ECI kit engine and it is really nice looking.
 
I'm facing the same decison right now.

I'm leaning towards AFP. I appreciate the support Don has provided on this site, and secondly, their kit is complete for RV's (except for hoses). I haven't seen a complete kit available for Silverhawk. If someone knows differently, I'd sure like to hear about it.

Roger, Tucson, AZ
 
Don at AFP goes the extra mile and works with you on any issues you have till its right, will help you set up your injectors to go lean of peak when you are ready, and seems to monitor the VAF forums and reply as warranted. Couldnt ask for more.

erich
 
Price a replacement diaphram or any other part from Precision, then price the equivalent from Don. I'll bet you'll quickly make up your mind then.
 
There is no choice. AFP is the only way to fly.

Call Don @ Airflow Performance and interview him, then call Precision. Precision was going to enforce their $200 minimum on my order when I called to buy a $.70 gasket to conform to THEIR AD on the hex nut. They told me "No exceptions", then a month later they were giving the gaskets away for free at SnF.

http://www.airflowperformance.com/

Call Don.
 
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Bendix, etc.

rocketbob said:
Price a replacement diaphram or any other part from Precision, then price the equivalent from Don. I'll bet you'll quickly make up your mind then.
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Ditto! If AFP's servo and Rod's air inlet will fit your cowl, I would definitely go that route. If the 3/4 inch extra length gets you; the Bendix RSA-5 would be my next choice.

Ditto on Don's service. All the people in his shop are top notch. They all go out of their way to help
 
A representative from Precision who came to one of our local RV meetings indicated that even though the system is similar/identical to the certified systems, authorized shops are not supposed to work on the experimental ones (Silverhawk), requiring work to be done by the factory only. This was 6 or 7 months ago, don't know if it is still the case. I've heard many say that they want the Precision experimental one so on the road work will be easier. May not be the case.
 
AlexPeterson said:
A representative from Precision who came to one of our local RV meetings indicated that even though the system is similar/identical to the certified systems, authorized shops are not supposed to work on the experimental ones (Silverhawk), requiring work to be done by the factory only.
Click to expand...

This is precisely why you should NOT use Precision, they do not support experimental aviation. Airflow Performance is in business to serve experimental aviation, support them.
 
Just another ditto for Don at Aiflow Performance. I went to his shop to have my Rocket injectors tuned. Great people, great service, and he supports us in experimental aviation. We need more vendors like Don.
 
You can get a complete SilverHawk kit from Mattituck that includes everything (fuel lines, injector lines, adel clamps, screws, instructions, etc).

Bob
 
Does that kit include the high-pressure mechanical pump? I'm looking to do the same conversion soon, but I'm wondering how big a deal it is to make my own fuel lines, get a Tempest pump from AC spruce, and the $2400 servo/distributor/nozzle kit from either Mattituck or Spruce.
 
Having used both, I'd say that overall I didn't notice a huge difference with either system...BUT (and this is a BIG but)..

Don Rivera will spend a LOT of time helping you out with any questions. He is smart, and really supports experimental aviation builders. I just wasted a ton of his time discussing injection for my Pratt 985, and guess what...I'll be using his stuff because I like his company.

Price being equal (or even close), I'd support the guy who'll support you!

Cheers,
Stein
 
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John,

It's been a while but I think that it had essentially everything FWF you need to install and/or convert a carb engine to fuel injection. That means that you'd need the high pressure electric pump but not the mechanical.

One thing I didn't like was that they supplied fiber lock nuts for the adel clamps so I swapped them for all metal. Interestingly a friend with a brand new Lycoming also had fiber lock nuts on those clamps.

I have no affiliation with Mattituck at all but have bought a couple of things (not an engine) from them. Mahlon Russell (one of their super techies) is a frequent contributor to the Lycoming Yahoo list, so while Precision might not necessarily experimental friendly, they certainly are.

I'd have no issue with either system!

Bob
 
The choice may have been made for me....

First of all, thanks for all the input, great discussion/info.

After the initial probing, discussion with both Precision and Airflow, I was leaning heavily towards the Airflow performance FM200 because of better perceived performance and product support.

What I've found is that the Rob Bower ram-air induction may have issues with the FM200, at least on an RV8 with an M1B. First is that he makes an adapter to fit the larger throttle body, and that adds about 1.5" to the length. The FM200 is also 3/4" longer. A local friend has his Rob Bower airbox extending beyond the smooth cowl and its sticking into the scoop he made. So moving out further possibly creates a bigger scoop out front.

And, my engine builder is now strongly recommending the RSA5. I'm waiting for an explanation, my guess is that they are just more comfortable with it in terms of setup. Plus they talked with Rod Bower and advised him thats the way its gonna go for me.

So Im putting all my trust in these guys and will use the RSA5. For me I never doubted that either solution was good, it was more of an exercise in optimization, which is something hopefully we all strive for.

thanks again-

Tim
 
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