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Vertical Draft Fuel Injection

Jonathan Cude

Jonathan Cude

Active Member
These Questions probably border on really stupid, but here goes...

I have a fuel injected IO-360, but the sump is vertical like a carb, not the forward facing one.

1. Electric Fuel Boost Pump... which one do i need and where do i get it! (Superior io-360, precision fuel injection (bendix clone?))

2. How do i determine cable length for Throttle and Mixture? Anyone have the numbers for this install?
 
What I did

Mine is also the Superior IO-360 XP Plus with vertical induction, kind of like a carb. I used the FI fuel pump from Van's. There are, I hear, other options, but this one at least came from a known source with some documentation. I installed it where Van's says to - immediately forward of the fuel selector. I then installed the fuel-flow sensor for my GRT between that and the firewall, went through the firewall where the carburetor version would have come out. I also then turned right along the firewall and installed the Andair gascolator, then looped back to the engine driven fuel pump with Van's rubber hose. There are certainly other ways to do all this, this is just information for you.
My throttle cable was OK. My mixture cable needed to be longer, but I goofed and got it a little too long. The good news is that you can cope with a little extra, but not a little to little. If you have manual trim, you will have to cope with the need for a longer trimcable (as in -8) or else, as I did, come up through the plumbing of the pump. Feel free to write directly if this is too confusing or if you have other questions. I'm not an expert, but I did survive this issue and am now in Phase 2.
 
I found that I needed a 50.5 inch throttle and mixture cable (both) for this set up. If you look at Van's catalog close enough, you will see that for the IO engine that is what's required. I found out the hard way and had to reorder. :mad:

Larry
 
Jonathan Cude said:
2. How do i determine cable length for Throttle and Mixture? Anyone have the numbers for this install?
Click to expand...
FWIW, I think I used 1/4" plastic tubing to "simulate" a cable run. Measured it out, and that was my custom cable length right there.
 
I had a couple of other issues I had besides all of the above. One was the length of the mixture control arm. There wasn't enough travel in the cable from Van's to get full rich and idle cut off. I drilled a new hole to shorten the length of the arm. Also I needed to fabricate a spacer to lower and align the FAB to the cowl air inlet. I can send pictures of my installation if you want.

Neil
RV-7 N748M
AEIO-360 B1B
 
I had a couple of other issues besides all of the above. One was the length of the mixture control arm. There wasn't enough travel in the cable from Van's to get full rich and idle cut off. I drilled a new hole to shorten the length of the arm. Also I needed to fabricate a spacer to lower and align the FAB to the cowl air inlet. I can send pictures of my installation if you want.

Neil
RV-7 N748M
AEIO-360 B1B
 
I have the vertical induction on my io-360 as well. For one more data point, my answer is virtually identical to the one provided by "Hevansrv7a" above. I however, did not install a gascolator. Most people with FI do not have one, although that is not to say its a bad thing.

erich weaver
 
Yes, please..

NeilMcLeod said:
I had a couple of other issues I had besides all of the above. One was the length of the mixture control arm. There wasn't enough travel in the cable from Van's to get full rich and idle cut off. I drilled a new hole to shorten the length of the arm. Also I needed to fabricate a spacer to lower and align the FAB to the cowl air inlet. I can send pictures of my installation if you want.

Neil
RV-7 N748M
AEIO-360 B1B
Click to expand...

Can you post a few pictures of your servo/airbox installation here? I have fabricated several spacers, but I'm trying to figure out what I want to do. I have to use a 1.5-1.75" spacer to get the airbox low enough to align with my cowl air inlet.

I'm trying to decide whether to use all that much spacer, or go with a 1" spacer and fabricate an inlet duct out of fiberglass that curves up to meet the FAB.

Thanks.
-Geoff
RV-8
 
Are you using the Sam James cowl or the stock cowl? If you are using the stock cowl, you probably don't need the spacer at all. The spacer is intended to make the height of the fuel servo the same as the carb. But you really don't need it...therefore you can do away with the upward bend of the airbox top plate.

Here is a picture of my setup (taken during construction):

p1000625.jpg

p1000896.jpg

p1010114.jpg
 
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It's an insulator, also

Scott Will said:
Are you using the Sam James cowl or the stock cowl? If you are using the stock cowl, you probably don't need the spacer at all. The spacer is intended to make the height of the fuel servo the same as the carb. But you really don't need it...therefore you can do away with the upward bend of the airbox top plate....
Click to expand...
I had a conversation with Superior about the spacer. They say it is an insulator. They couldn't say what happens without it, but it's there to keep the TB cooler, not only for dimension adjustment. Just FYI.
 
Counterpoint: In my conversations with Aero Sport Power, they indicated it wasn't needed. They didn't even ship me one! Engine has been running great without it.
 
Huh?

hevansrv7a said:
I had a conversation with Superior about the spacer. They say it is an insulator. They couldn't say what happens without it, but it's there to keep the TB cooler, not only for dimension adjustment. Just FYI.
Click to expand...

I always thought a "TB" was a turn and bank indicator but obviously here it refers to something else.....give us a clue.
 
Captain Avgas said:
I always thought a "TB" was a turn and bank indicator but obviously here it refers to something else.....give us a clue.
Click to expand...
Presumably TB = throttle body
 
dan said:
Presumably TB = throttle body
Click to expand...

Yeppers. In the automotive world, it's a common abbreviation. Also t/b. As with aircraft, injected cars and trucks will run upside down. Ask me how I know... :eek:
 
Need for spacer.

hevansrv7a said:
I had a conversation with Superior about the spacer. They say it is an insulator. They couldn't say what happens without it, but it's there to keep the TB cooler, not only for dimension adjustment. Just FYI.
Click to expand...


OK, we've established that the TB is in fact the FI servo unit and that presumably Superior claims you need a spacer between the sump and the servo for "insulation".

Does that make any sense. I imagine that lots of vertical updraft Lycomings have no spacer between the sump and the servo. Can we clarify this.
 
No clarification, just theory

Captain Avgas said:
OK, we've established that the TB is in fact the FI servo unit and that presumably Superior claims you need a spacer between the sump and the servo for "insulation".

Does that make any sense. I imagine that lots of vertical updraft Lycomings have no spacer between the sump and the servo. Can we clarify this.
Click to expand...
I cannot comment on your observation - a good one. However, an insulator would have the effect of keeping the fuel cooler as it goes through the metering mechanism of the TB (Throttle Body) and it would delay the warming of the air until it was inside the sump. Important? I don't know. We've now exhausted my knowledge of the subject. I will add that it is "fact" according to Walter Atkins that Superiors are stronger right out of the box than are Lycomings for the same specification (such as IO-360). I'm sure there are other factors involved, but he attributed it to volumetric efficiency. These comments were in previous posts on VAF.
 
Spacers and bends...

Scott Will said:
Are you using the Sam James cowl or the stock cowl? If you are using the stock cowl, you probably don't need the spacer at all. The spacer is intended to make the height of the fuel servo the same as the carb. But you really don't need it...therefore you can do away with the upward bend of the airbox top plate.
Click to expand...

Stock cowl.. If I don't use the spacer, the entrance to the airbox doesn't line up with the entrance to the cowl because the injector servo is shorter than the carb would be. Here's what it looks like:

airbox3-w.jpg


A 1.25-1.5" spacer seems to work best for me. It lowers the airbox to align it with the opening in the cowl. It also prevents me from exchanging my fuel servo for the one you have (where the mixture arm points up instead of down), and I don't have to make the little cutout in the side of the airbox to accommodate the mixture arm.

I still need the upward bend in the airbox top plate in order to make the opening in the airbox the same size as the cowl (2" vertically). Without the upward bend, my airbox opening would only be 1.75" vertically. Without the spacer, I'd have to make a downward bend in the airbox top plate and cut off / remake the fiberglass bottom of the airbox at the entrance.

Here's a pic with the spacer:

airboxspacer-w.jpg


On a completely different topic (still airbox, though), what kind of clearance do you have between the left side of the airbox and the cowl? The servo isn't centered under the engine. I shifted my airbox as far to the right as I could, given the location of the pre-drilled holes in the mounting plate. But I ended up with less than 1/2" clearance between the airbox and the cowl. That doesn't make me happy, but I'll live with it if that's the way it's supposed to be. Here are some pics of that:

airboxclearance1-w.jpg


airboxclearance2-w.jpg


Thanks in advance for any comments/suggestions..

-Geoff
RV-8
 
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Geoff:

Maybe something is different with the -8 cowl, but I can tell you that

a) I have a ton of clearance around the airbox on my -7A.
b) Without the spacer my top plate was about 1/8 lower than the scoop.

Weird. :confused:
 
Geoff, that looks like trouble...

Not enough clearance. When the engine starts up and shutdown there is a lot of movement. I think that you will have the cowl knocking on the side of your airbox.
I had a similar issue with my mixture control on my IO-320. I needed to cut a small relief in my cowl and made a bubble about 3 inches around.
I think that you will need a good 1.5 inches to be safe.

Kent
 
Spacer location

hevansrv7a said:
I cannot comment on your observation - a good one. However, an insulator would have the effect of keeping the fuel cooler as it goes through the metering mechanism of the TB (Throttle Body) and it would delay the warming of the air until it was inside the sump.
Click to expand...

I see in Post # 17 that Geoff shows the spacer as being between the Servo and the FAB (not between the sump and the Servo). That's where I always thought a spacer would go. If that's the case then the spacer provides no "insulation". I'd like to get to the bottom of this. Does anybody put the spacer (if required) between the Servo and the sump.
 
What Mattituck says...

Captain Avgas said:
I see in Post # 17 that Geoff shows the spacer as being between the Servo and the FAB (not between the sump and the Servo). That's where I always thought a spacer would go. If that's the case then the spacer provides no "insulation". I'd like to get to the bottom of this. Does anybody put the spacer (if required) between the Servo and the sump.
Click to expand...
In all the emails I've exchanged with Mahlon at Mattituck, he's said to put the spacer between the servo and the FAB. He's even seen a picture of my spacer installation and said that's the way it's supposed to be.

I'm not saying anyone else's opinion is wrong, but since I bought my engine from Mattituck, I have to go with the advice I received directly from the Mattituck expert.

-Geoff
 
Did anyone who is interested in this thread receive a spacer with their engine? I took delivery of a Superior IO-360 with updraft FI two weeks ago, for installation in my RV-7. I don't remember seeing a spacer in any of the boxes included with the engine, but then I probably didn't look that closely.
 
Good Posts, keep em coming, I took delivery of my XP-IO-360 a month ago, cant remember the spacer either, got to have a look again over the weekend.

Thanks Guys.
Regards,
Rudi
 
Yes I got a spacer from Superior

Lars said:
Did anyone who is interested in this thread receive a spacer with their engine? I took delivery of a Superior IO-360 with updraft FI two weeks ago, for installation in my RV-7. I don't remember seeing a spacer in any of the boxes included with the engine, but then I probably didn't look that closely.
Click to expand...
The spacer is only about 3/8 or 1/2 inch thick, dark grey. It goes between the sump and the throttle body. There are also gaskets and in my case the Van's bracket for cables, all above the throttle body. It came with my engine which in turn came with the fuel injection unit from Precision.
 
hevansrv7a said:
The spacer is only about 3/8 or 1/2 inch thick, dark grey. It goes between the sump and the throttle body. There are also gaskets and in my case the Van's bracket for cables, all above the throttle body. It came with my engine which in turn came with the fuel injection unit from Precision.
Click to expand...

Thanks. Something to look for next build session. I'll admit that when I first opened the engine box I wasn't very calm and rational.
 
Spacer issues

I forgot about this thread... I need a spacer to provide clearence (Clarence) between the FAB and the mixture/throttle arms. I think I could have got the FAB to align with the cowl without one but not really sure there. The spacer did help that. I have a Bendix RS5 (I think) servo. I had the spacer fabbed by a local machine shop and it's about an inch thick and slightly tapered to aim the FAB more directly at the cowl inlet. I also had to shove the FAB as far to the right as possible to get it to aim at the cowl inlet. I had to fabricate the top plate of the FAB to get that to work. Since I was already making one I made it out of thicker stock as well since there have been some reports of that part cracking.

Neil
 
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