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Rolling your own induction

I modified mine for a bigger filter and to create enough starter clearance (mine wouldn't fit as it came from Van's). But making a new one from scratch would be a pain.

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I worked the Van's FAB into shape

Hi Ryan,
I agree with Heinrich. The Van's Horizontal FAB may not (almost certainly will not) fit your engine/baffles/cowling without much modification but it would be much, much harder to build your own from scratch.

I cut the FAB in half, fitted the bottom end, fitted the top end then made good the join in the middle. Also had to make clearance for the alternator bracket and no.2 cylinder oil line.

If you're in Dan H's fibreglass fabrication league then I'm sure it would be no issue to build your own but for a fibreglass novice like me, making the Van's FAB fit was the right way to go.
 
OK thanks guys..sounds like starting with Vans fab is the way to go. I am defiantly not in DanH league of fiberglassing. I assume with the Rod Bower Ram air canister then Vans fab is not needed at all? I am considering this route too.
(forgot to mention the engine is IO 360 A1A 200hp, forward facing sump)
 
Now that Ive done it...wouldnt do it again

Hi Ryan,
I had the same thoughts as you, so I decided to make my own.
Steps:
1: Make wood attachment block at attached to injector
2: Make wood copy of filter and attach to baffle
3: Join both with aluminium tubes at each corner, bending as required to make a shape that fits around everything and clears the cowl. (BTW hadnt fit my cowl yet....first mistake)
4: Fill inbetween the tubes with foam, spray foam etc and smooth.
5: Cover with plaster and sand.
6: Fit cowl (This should have been 1)
7: Attach sanded plug into position.
8: Try to put cowl on.
9: Swear.
10: Swear again.
11: Take off cowl,
12: Hack mecilessly at plug destroying previous nicely smoothed shape to fit cowl.
13: Replaster
14: Resand
15: Paint, and polish
16: Finally!! Wrap with glass. Cant bag it...too wierd a shape...so wrap with saran wrap.
17: Wait.
18: Peel off saran wrap.
19: Swear at voids because of no bagging
20: Sand, reglass voids, fill and sand.
20a: Wait some more
21: Refit.
22: Look at transition from duct to venturi. Rework interior with ramps to smooth transition.
23: Fill and sand again.
23a: Wait .......
24: Refit
25: Put cowl back on.
26: Check clearances again....VERY difficult to get sight line
27: Dont like clearances....remember engine shakes.
27a: Swear for quite a while this time.
28: Remove cowl
29: Slice forward part of duct off, reglass, refit.
30: Done.


There ya go.

Good thing I only make $0.23 an hour!!!

Chris
 
-A1A may help

Your -A1A may well help. Mine is an -M1B and I suspect that the Van's FAB is a better fit to the -A1A than to the -M1B.
 
I am on a 3rd induction method with the horizontal AFP system and must conclude it has been much work and not much difference in performance except the straight ram air intake works fine in flight.

First I tried a modified version of the Van's unit. I pitched it as it took too much space.

Second I build an aluminum box with a filter and connected it with 3" scat. I was ok, but the filter was too small.

Third I am using an internal, quite large K&N cone filter, and it too works ok. The ramp in front of #2 cylinder is now closed for (perhaps) better cooling.

I still suffer nearly an inch loss of manifold pressure on take off and don't like that one bit, but once in the air, ram air is introduced and the engine likes it very much. This is flying in hot summer air, it will probably be much better on take off once temps come down a bit. (I still do get off in less than a 1000' most day. :)
 
shuttle said:
Your -A1A may well help. Mine is an -M1B and I suspect that the Van's FAB is a better fit to the -A1A than to the -M1B.
Click to expand...

I have heard two different stories on this... one is that the Van's horizontal filtered airbox only fits the A1A and doesn't fit the M1B. The other story is that there is a FAB for the M1B that has a different part number. Anyone know the real truth? It won't be too long before I need to order one!

thanks,
mcb
 
Ryan a friend of mine and I developed a new ram air scoop for our Rockets and it works great, won't be very much work to transplant to an -7. I'll post some pics tonight.
 
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vans is a good starting point...

the vans snorkel is a good starting point but be prepared for quite a bit of work to get a good fit, especially if you need to modify the fuel meter side for an air flow performance setup. as supplied the snorkel is prepared for a smaller opening with a flange connection that needs to be chopped off and enlarged for a slip fitting.

i ended up cutting the snorkel in half and fitting the pieces separately to get acceptable clearances then rejoined them. the rejoin was slightly offset and turned but was pretty easy to mate up by slicing fingers and using some heat to blend the shapes... wrap it all with duct tape and start glassing inside, remove tape and glass the outside... then sand and finish to make the inside smooth.

i had this part in my hands for many many days during the build... glass and sand, glass and sand...

now flying it works pretty darn good.

the surgery shot...
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after fitting each side separately
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inside shot of the join with sliced fingers to blend the halves
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the finished product installed
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mburch said:
I have heard two different stories on this... one is that the Van's horizontal filtered airbox only fits the A1A and doesn't fit the M1B. The other story is that there is a FAB for the M1B that has a different part number. Anyone know the real truth? It won't be too long before I need to order one!

thanks,
mcb
Click to expand...

Matt,
It is true that there have been two different designs for the Van's Snorkel.

My one is the same as the one in Stephen's photos below (VA-132-1).
The physical difference as I've seen it in photo's is that the newer VA-132-1 has a flat surface on the lefthand side where the alternate air door goes. The VA-132-1 is spec'd by Van's for both the -A1A and the -M1B. I suspect the earlier design was made just for the -A1A. Rene Bubberman's PH-VII website shows photos of the earlier design.

The challenge I had at the top (air filter) end was getting the snorkel to align where I wanted the hole to be in the baffle ramp. The uncut snorkel put the hole too far forward in the baffle ramp. By separating the top half of the snorkel I was able to move the baffle ramp hole back about half an inch which much improved the positioning of the front edge of the hole relative to the front edge of the baffle ramp and also the cowling inlet.

The other thing I ended up doing was building out a 3" dia round extention in that flat outside surface to position the Alt Air Door in appropriate alignment for the control cable run under the rocker box covers.

Hope that makes sense :)
 
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So you're saying there are actually two airboxes that won't fit the M1B? ;)

We appear to have the same setup, so I'm sure I will be following in your footsteps when I get to that point.

thanks,
mcb
 
FYI

Matt,

Pg 10 of accessory catalog says...

Filtered Airbox - Horizontal Draft
FAB System for:
180hp (IO-360M1B) or
200hp (IO-360A1B6)
in the RV-7/7A and 8/8A ONLY

.BTW, Mine went on a Superior IO-360 and had to cut it in half , glassed the gap, not that bad, just a moderate amount of swearing at the time... Yes, completed the cowling first.

.
 
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My FAB fitted the -M1B

mburch said:
So you're saying there are actually two airboxes that won't fit the M1B? ;)

We appear to have the same setup, so I'm sure I will be following in your footsteps when I get to that point.

thanks,
mcb
Click to expand...

I have a Lycoming YIO-360-M1B and the FAB fitted without a problem.
The only modification required was for the alternator bracket.

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Made a drilling jig


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To drill the holes accurately


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1/8" clearance between FAB and starter


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Trimmed the top


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For clearance to the ramp


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With good results


The only modification required was for clearance to the alternator bracket
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Cut the FAB


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And re-glassed.
 
Hi Andre,
Glad your's went in easy. Wish mine had. That looks a nice clean install.
Lots of variables come to play here I think.
Your's is on an -8, mine's on a -7 (cowling/baffle differences?)
Your starter is different to mine.
Etc, etc.
 
rocketbob said:
Posted 08-25-2010 Ryan a friend of mine and I developed a new ram air scoop for our Rockets and it works great, won't be very much work to transplant to an -7. I'll post some pics tonight.
Click to expand...

Where are the pics Rocketbob? I building a 7 I'm looking into doing something too.
 
yakdriver said:
Rod Bowers has a really nice air intake scoop. His whole filtered system works great. Don
Click to expand...

From his site:
Designed for FUEL INJECTED MOTORS with VERTICAL and FORWARD FACING SUMPS.

Does anyone have a few pics of a 7 with his setup with FF induction (smooth cowl)?

yakdriver said:
Hey Carlos, I did the test flights on a friend's PL-1 and I'm also one of the few to fly the Pazmany Storch. Don
Click to expand...

Not the fastest or most room (hence the RV-7) but fun to fly wasn't it? I miss it.
 
pazmanyflyer said:
From his site:
Designed for FUEL INJECTED MOTORS with VERTICAL and FORWARD FACING SUMPS.

Does anyone have a few pics of a 7 with his setup with FF induction (smooth cowl)?



Not the fastest or most room (hence the RV-7) but fun to fly wasn't it? I miss it.
Click to expand...

What was interesting is I flew the test flights on another friend's RV6A with the same exact engine and prop combination as the PL-1 within a couple of weeks. The 6 is 40mph faster than the PL-1. I have to say the PL-1 was built like a bridge. Don
 
Van's snorkel didn't fit my ECI IO360 with cold induction and Silver Hawk at all. I tried to modify it by cutting it in half, splitting part of it and removing all the areas that interfered with the alternator etc but finally just threw it away and built my own.

Made a shape from foam blocks and used a carbon fiber sock and WEST.

It was a lot of work but the results are worth it.

It can be done.
 
Paul K said:
Van's snorkel didn't fit my ECI IO360 with cold induction and Silver Hawk at all. I tried to modify it by cutting it in half, splitting part of it and removing all the areas that interfered with the alternator etc but finally just threw it away and built my own.

Made a shape from foam blocks and used a carbon fiber sock and WEST.

It was a lot of work but the results are worth it.

It can be done.
Click to expand...

I'm running into same situation. ECI IOX360w/7 degree cold air. Lots of modifying around alternator bracket, but still think the fab is a great starting point. I also had to cut the snorkel in half and rotate it, because I need to compensate for the 7 degree tilt from fuel fuel servo, to correctly mate up to the fuel servo.
 
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