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Rod Bower Ram Air IO360 forward injector

Larco

Larco

Well Known Member
If anyone has the Rod Bower Ram Air system installed on a IO360 with forward facing injector, would you please either post or send me a picture of the system installed? Some private comments would also be appreciated, positive or negative. I am considering installing one on my RV-7 and any guidance would be appreciated as well. Thanks, Larry
lschneider39 at cox.net
 
Likewise for me. I called Rod and asked questions recently and after the conversation I was concerned that the scoop he sold me may not fit around the filter housing as he mentioned that I might have to space the scoop off the cowl a bit to get clearance. Not something I want to deal with.

I also wonder if there is any real performance gain over the snorkel intake setup?

Randall
 
When filtered, the stock Vans snorkel from the left cowl intake is much superior. The Bower system draws its filtered air from inside the lower cowl (hot, and low pressure) and does so against its own plastic flapper valves.

When running unfiltered, the Bower intake provides a little more MP. Unlike the Bower, the Vans snorkel filter can't be removed from the airflow in flight, and its size is limited by the available intake ramp area.

It is possible to build a fully filtered system with restriction comparable to an unfiltered Bower. The trick is merely finding enough space for a lot of filter media area.
 
With the RV-7A I seriously considered the Bower ram air system but finally decided to roll my own over the cost issue.

I bought the valve from AFP and a ring from Sam James to provide the ram air intake. It took some cowl glass work to get it to fit but was not too big a deal. For filtered air there was an internal K&N cone filter connected to the other side of the AFP valve intake.

There was performance loss using internal filtered air, but as soon as the ram was opened after take off, the engine responded noticeably. It was ok but not optimal.

With the RV-8 it is the snorkel and so far i am most satisfied with it.

FWIT Dan Checkoway has reported there is little or no performance improvement with ram air over the snorkel.
 
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I have the Rod Bower ram air and just starting on the Sam James cowling install. Would love to see some pictures from others with the same combo. The lever to flip the door open and closed sticks out to the side and hits the cowling meaning an ugly bump-out. I'm thinking of twisting the whole ram air intake it so the door lever is on top, just not sure how well it will work there plus the engraved front of the flap door would now be sideways. Perhaps I could just flip the door over, need to see how easy it is to remove the tiny screws holding it on without stripping them.
 
I put the RB unit on with vertical induction, forward facing FI and crossover exhaust. It was a serious PITA and Rod had to mfg some custom spacers for me. Check out my blog for pics. As for the RB unit, I wouldnt do it again for reasons I have stated on here previously. I dont want to keep rehashing it publicly so if you want to know more, send me an email at ronduren5 "at" hotmail.com
 
I like my Bower RamAir. Works exactly like I thought it would. Yes it takes warm cowl air until Ram Air is opened, but that is ok for me. WHen open I think it adds a bit of horsepower.



install pics




Clearance issue with the James Cowl, I ended up cutting the cowl and reglassing it for spacing. No bump though.
 
Rod bower ram air

I don't know if this helps - I continued my plennum straight down to the bottom of my cowl. Behind the air filter and in front of the sump. I have an IO-540 with a forward (horizontal) facing sump (stock Vans is vertical placed). Now I get only cold air to my filter, and nearly all the air entering goes over the cylinders.

35mmglg.jpg
 
Evolution10 said:
I continued my plennum straight down to the bottom of my cowl. Behind the air filter and in front of the sump. I have an IO-540 with a forward (horizontal) facing sump (stock Vans is vertical placed). Now I get only cold air to my filter, and nearly all the air entering goes over the cylinders.
Click to expand...

The lower bulkhead is an interesting approach, usually seen only with Steve Wolf acro cowls and Continentals. Makes sense with the AC compressor installation, as the alternative is a huge leak in the intake ramp for the belt, or a convoluted ramp floor.

Got more recent photos? I'm not sure what you're doing to complete the sealing. The lower front bulkhead would get a flap seal, as would the small cheeks outboard of the front cylinder heads. However, why the plenum lid, and how are you sealing to the upper cowl or intakes?
 
Not really

Everyone seems to think that you are getting a few more horsepower when you open this unit to bypass mode. Really, what you are seeing is the difference in a choked engine. I have now removed 2 of these from RV-10's. The engine was dramatically choked at takeoff power as evidenced by activating the bypass during the takeoff roll and witnessing a dramatic surge in power and a much more normal takeoff roll and climb profile.
Van's standard set up really does work OK. :)

Vic
 
DanH said:
When filtered, the stock Vans snorkel from the left cowl intake is much superior. The Bower system draws its filtered air from inside the lower cowl (hot, and low pressure) and does so against its own plastic flapper valves.

When running unfiltered, the Bower intake provides a little more MP. Unlike the Bower, the Vans snorkel filter can't be removed from the airflow in flight, and its size is limited by the available intake ramp area.

It is possible to build a fully filtered system with restriction comparable to an unfiltered Bower. The trick is merely finding enough space for a lot of filter media area.
Click to expand...

Dan,
I have an early bower system on my 7. It uses ram air for filtered, not sure why it was changed to pulling air from inside the cowl.
imagecvh.jpg
 
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Thanks everybody for the taking the time to respond, great input. My concerns have been addressed so back burner for now. I'm actually quite happy with the current filter system but was looking for another inch up high like I had on the O-360 RV6. But not at the sacrifice of power on the take off roll. I was worried about that scenario. Larry
 
vic syracuse said:
Everyone seems to think that you are getting a few more horsepower when you open this unit to bypass mode. Really, what you are seeing is the difference in a choked engine. .....Van's standard set up really does work OK. :)

Vic
Click to expand...

I have flown with several other RV's and always carry more MP than they do. I agree that the surge I feel and hear when first opening the ram is a false sense of power. I guess the ramair doesn't add HP, but it does maintain that power to a higher altitude. 10500 (11500DA) I'm still getting 21.5". 8500 I'm around 23.5-23.8".

so, +MP= more HP.

I open my Ramair after I get up out of the bug zone
 
Brian, I noticed in your picture you mounted the arm on top instead of the side which is what I'm contemplating. What did you do about the door? Did you leave the engraving facing forward and sideways or were you able to reverse the door so the engraved face is now inside?
 
door is unchanged, I just rotated the whole canister about 45* to clear the cowl.

BTW, I have the larger filter housing meant for a 540. I got it used(unistalled) from someone who went a different route, so saved a bit of money. But had some fitment issues stuffing it in the James Cowl.
 
best of both worlds

Here's how I did my ram air inlet. Similar to Bower, except mine pulls filtered air from the cooling ramp.

See this link:
http://www.vansairforce.com/community/showthread.php?t=49556&highlight=ram+air+intake

I'm very happy with it, but......

As Dan H. says, and as Dan Checkaway proved, a well designed filtered intake in the cooling ramp can achieve almost the same MP with cleaner cowl lines, and less build effort. Key is not only to put as big a filter as you can fit in the cooling ramp, but also put radiused lips around the perimeter to avoid flow separation at sharp corners at the intake.

If/when I do it again, that's what I would do.
 
I don't have a Rod Bower System, but I do have a RAM air system similar to DanH's. Actually I installed the same filter and copied it (thanks Dan :D). Previously I had the Van's FAB, so the changes involved replacing the exhaust, adding a Superior Cold Air sump and re-glassing the lower cowl.

The new filter is a lot nicer in that it doesn't have all the issues associated with the FAB eating itself and getting full of fluids. On the performance side I have noted very little difference.

Vans stock filters are very good. The Rod Bower unit is known to perform poorly until it is opened. I can't see the Sam James unit being too good either given the limited media area.

I would stick with stock. They work great. You might be able to do better than Vans but there is very little to be gained in the first place and you will expend a lot of effort.
 
Steve, I like what you did. The only problem with my install is it is in a Sam James cowl and plenum so there is no intake ramp to pull the filtered air from.

Perhaps Dan can put his two cents in here and hopefully I describe it well enough to understand my thought. How about a snorkle intake around the existing intake. The inner part is the ram air intake and the outer ring of the intake would bring in direct air to the sides of the ram air unit for filtered air. When the door is opened the ram air will cause a higher pressure and reduce the amount of filtered air coming through. Inside the snorkle is some runbber/baffle seals so the cowl can easily be put on and removed. This seals will keep the air coming in from the outer filtered air intake from blowing through under the engine.

Dan H., I looked over your posts through the links but most of the pictures are gone now. I only saw the final product but it looks a little too big to fit inside the Sam James cowl. I remember from many years ago seeing Dan Checkoway's ram air build for his -7 on his site but all his stuff is long gone.
 
hydroguy2 said:
I have flown with several other RV's and always carry more MP than they do. I agree that the surge I feel and hear when first opening the ram is a false sense of power. I guess the ramair doesn't add HP, but it does maintain that power to a higher altitude. 10500 (11500DA) I'm still getting 21.5". 8500 I'm around 23.5-23.8".
Click to expand...

Better calibrate that MP gauge.

Capflyer said:
How about a snorkle intake around the existing intake.
Click to expand...

Take a look at the intakes on the Showplanes cowl for the RV-10

Dan H., I looked over your posts through the links but most of the pictures are gone now.
Click to expand...

I've moved them to a better host and re-posting as time allows. Airbox post now fixed.
 
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I have the system and no mp differences with the standar snorkel. If i build a new plan i will not consider again the ram :(
 
DanH said:
Better calibrate that MP gauge...
Click to expand...

I checked it again today, it appears I have an error of about .4"MP. I haven't checked it since phase 1, so looks like I have a sensor going south. Now, I wonder if that's why my % power hasn't seemed correct for a while.
No way to adjust it, so looks like I need to order a replacement.
 
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