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Honda 1.8L on RV6A Now Flying!

If I recall correctly, the system requires passing through it at every taxi. It's now done with the least possible manifold pressure, rather than shoving the throttle to pass through it quickly?



I posted four Holzer examples earlier, since deleted. As you know, your system can be modeled when you find reason to dismantle the Marcotte for accurate measurements. No point in GIGO.

As before, the urethane bushings are a poor choice for two reasons. The model would show you one of them. And there is still the mystery of the rod bearing failures.

Yes, idle speed above the resonant range, a desirable design goal. No flywheel makes it more impressive. It didn't happen using the million monkeys approach.


Correct, I pass through the resonant range as I start the taxi, bringing the throttle up quickly and commence taxi above 1300 rpm (590 prop rpm).

I hope I don't find reason to dismantle my drive any time soon, but I will at the first sign of spline wear, bearing scratchiness, increased backlash, signs of metal in the oil or increased GB oil temps. I do look at the coupler bushings more often now and I'll pull the vacuum pump at 100 hours since overhaul to see what that coupler looks like.

Yes, still no firm reason for the rod bearing condition. Could be TV related or not.

The urethane engine mount bushings, probably not the best choice but others have experimented with them here and other places. They work. This engine is much smother than a Lycoming. I inspect the mount ever time the cowling is off which is pretty often hour-wise.

Yes, my FWF package is a lot more experimental than most. I realized that from the start when I was designing and building it. I've been happy with the performance and education I received in doing it despite some "moments", frustration, head scratching and do-overs on some parts.
 
I do look at the coupler bushings more often now and I'll pull the vacuum pump at 100 hours since overhaul to see what that coupler looks like.

The coupler bushings between the flywheel and the gearbox are the ones I had in mind. I suspect the model will suggest a much lower spring rate, and anyway, urethane has too much hysteresis.

yes, still no firm reason for the rod bearing condition. Could be TV related or not.

Here's the theory. The prop is the major inertia, the anchor against which the rest of the system oscillates. The Marcotte ring gear bell is massive, likely be both very stiff and high inertia (http://www.glasairproject.com/GlasairI/images/guymgear.jpg). So, the F1 node, typically assumed to be close to the prop (i.e. in a PSRU's prop shaft) could be pushed toward the flywheel. If true, the oscillating inertia, being just the crank, would be reduced, thus its frequency would be higher. Imagine what significant oscillation would do to the oil wedge in the rod bearings.

If correct, your subsequent higher inertia flywheel assembly should help. Devising an experiment to prove or disprove would be, ummm, noble ;)
 
The coupler bushings between the flywheel and the gearbox are the ones I had in mind. I suspect the model will suggest a much lower spring rate, and anyway, urethane has too much hysteresis.



Here's the theory. The prop is the major inertia, the anchor against which the rest of the system oscillates. The Marcotte ring gear bell is massive, likely be both very stiff and high inertia (http://www.glasairproject.com/GlasairI/images/guymgear.jpg). So, the F1 node, typically assumed to be close to the prop (i.e. in a PSRU's prop shaft) could be pushed toward the flywheel. If true, the oscillating inertia, being just the crank, would be reduced, thus its frequency would be higher. Imagine what significant oscillation would do to the oil wedge in the rod bearings.

If correct, your subsequent higher inertia flywheel assembly should help. Devising an experiment to prove or disprove would be, ummm, noble ;)

The present redrive coupler bushings are really low stiffness, I measured them at 25 lb/ft./ degree (collectively). Given the strange marks on the bushing bores and the condition of the bushings, I wouldn't attempt anything with lower stiffness nor would I use urethane there. Would be interesting to install bushings with triple the stiffness and observe the results. I just can't find any. It works well enough for my purposes at the moment.

At some point, maybe the engine will be apart again and I can take a boo at the bearings. Certainly curious but couldn't conclude with certainty whether the flywheel mass changed that aspect.

While some things may universally apply to auto conversions and TV, I think we should leave this thread to discuss Charlie's results rather than mine at this point. There is another long thread on my experiences here already. Given my seriously limited time to even fly these days, I won't be doing any FWF mods to my plane for a while.
 
The present redrive coupler bushings are really low stiffness, I measured them at 25 lb/ft./ degree (collectively).

That's interesting. Very soft indeed, which makes the question "For how many degrees?" It's a pin in a socket, soft only until the pin reaches the edge of the bore. At 25 ft-lbs/deg (1.942 kNm/rad), the coupler would have to have around 10 degrees of displacement just to handle nominal torque, not cyclical peak, nor resonant. Don't think you have it available, my friend. The pins are hard against the wall, which is why it hammers.

Seriously, consider a basic analytical model to establish a desired coupler stiffness, then choose something like a Centaflex A. All the values are known, so it lends itself to design rather than "experimenting". I'm just sayin'.

http://www.centa.info/data/products/32/int/cf-a--en-17-15lowres.pdf

... I think we should leave this thread to discuss Charlie's results rather than mine at this point.

You got it.
 
Fellas, just for the record I have been off the grid for a few days out of state. The TV discussion is interesting and important, and I am sure many will enjoy reading about it.

My main goal at this point is to get the engine mounted on the airframe and up and running. I just don't like the engine being sidelined for long periods of time.

There will be some "plumbing" challenges with the cooling tubes and intake pipes for sure. Hence I will have to remount the TB and of course create a new throttle linkage systems.

....can't wait!

Charlie
 
Ross, I will ask Jan about testing he has done that prompted him to cut the disc.

Charlie, would you care to share his response?

Dan share with us if you get the Newton Meter ratings on the GAB01-017.

As noted, I wrote to ask for the values required for torsional design, as spelled out in SGF's own published guidance (copied below). The response today was "Unfortunately we are not allowed to share internal company data."...meaning that particular coupler is a proprietary BMW part number.

It is possible to determine static torsional stiffness by measurement in the field, but dynamic stiffness and all the rest would be a guess, assuming someone actually wished to design a torsional system. I recommend switching to a coupler for which design data is available.

____________________________

Is it possible to obtain the following design/application data for the SGF GAB01-017 driveshaft coupler?

TKN
TKMax1
TKMax2
TKW
∆TMax
∆Kr
ΔKa
∆Kw
Ct and Ctdyn
Cr
Ca
Drel and ψ
PKW50
nmaxDauer
nmaxKurz

Thank you.
 
I did ask Jan at Viking on a Zenith forum asking why the disc was cut and Jan replied ...

"Viking only use the OEM part and modify it according to the torsional damping required by a particular engine / gearbox / propeller combination. "

I follow up after that answer with more questions tonight asking for more details about the testing.

regardless, unless troubles surface I am comfortable using this BMW driveshaft coupling. ( but at this time of my testing I am choosing to leave my disc whole, not cut)

There are two factors that are meaningful to me. 1) There are about 500 of the viking engines and or gearbox sold and in some degree of use, and I have only heard of one"failure". From what I know based on what is shared in a viking video it was not a caused by a failure of the disc but rather the 3 prong spyder flange; and that part as since been beefed up so it has a larger flange base.

The other reasons I am comfortable with the flex disc, is that they are in use and have been for years in most of the BMW on the road. Yes, I do completely understand that their use in a automotive driveshaft is different than as an interface coupling between a engine and gearbox. But in fairness, there is also nothing that shows that it is not a perfect interface device between the engine and gearbox.

Charlie
 
radiator process

Update:

I am beginning the radiator phase. As I have often done, I am going to take advantage of what others before me have done, and for me this means copying what Ross at SDS did on his RV6A. (I know he benefitted from others doing this too).

Here are 2 pics from Ross' page.

Question for Ross if you see this post..... Can you confirm the amount of attachments for the radiator itself, is it just these bolts circled in red at the top ends of the radiator? did you capture the "L" angles with 3/16th bolts?

Thanks.

oWS.jpg


another shot of Ross' radiator install that I plan to copy...

oWV.png


I have a request for a quote from a local radiator shop to build it for me, I believe it will be about $400 to be built.

Charlie
 
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There were a couple .063 vertical tabs welded to the rad tanks with 2 nutplates on each. Two 90 degree angle brackets were riveted to the belly skin with some heavy doublers sandwiched in between. These allowed me to hang the rad and hoses. The rad is really held in place mostly by the scoop. It fits into the recess you can see in some of the other photos.

You'll notice that only the core is wetted, the tanks are not in the airstream like many installations where people get lazy. My coolant hoses and connection are also out of the duct airstream.

Note the guide vanes on my installation. Through flow testing, I found these were required to avoid separation. Russell Sherwood found the same thing in his testing yet you'll find that hardly anyone else uses them.



Above is a photo of a Thunder Mustang setup. Superb composite work but terrible execution inside the rad duct with a big, flat wall of sheet metal for the air to hit. Lots of drag and lots of turbulence. Don't do something like this if you are trying to keep the drag low. Stacked coolers creates even more momentum loss. IMO, it's better to use a good water to oil cooler and enlarge the rad a bit to compensate for the higher heat flow to the coolant.
 
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Ross,

Thanks for the quick response. Yes, I do understand that the scoop structure also plays a role in supporting the radiator.

I also understand that the importance of channeling the air in to just he core area of the unit is important.

I can tell you and the followers here that since I plan to build my scoop out of .032 aluminum sheet, it will not be nearly as nicely rounded as what you built using wood and fiberglass. But I do plan on enclosing the whole radiator and hoses inside the scoop, and then add additional walls inside the scoop to channel the airflow to only the core area.

I am not sure yet on how I will channel the air from the engine compartment, so it does not go in to the scoop. I may have to split the fresh air in to two inlets on the sides, and funnel the cowling air in the middle and aim in downwards. I think once I get things going it will become obvious.

Thanks again.

Charlie
 
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Another aspect I am considering is the use of a manual valve in the bypass loop, or the heater core loop.

They look like this.

oWg.jpg


Ross, do you or anyone out there have any experience with these... good or bad?

Seem like it would be easy way to adjust coolant flow, much like the purpose of the adjustable exit ramp after the radiator...

Charlie
 
Charlie- Nice looking package! Do you happen to know the design duty-cycle of this engine? (time permitted at full power, or % power permissible for continuous operation). - Otis
 
Charlie. I used one of these initially as a heater valve. When I did my big overhaul in 2013 I removed the heater core from behind the panel and all the coolant passing though the cockpit. I just took hot air off the heater core/ supplemental rad mounted FWF. Works well.

I'd just use a standard ball valve if you want to restrict coolant flow somewhere. Cheaper and more robust/ reliable.
 
Charlie. I used one of these initially as a heater valve. When I did my big overhaul in 2013 I removed the heater core from behind the panel and all the coolant passing though the cockpit. I just took hot air off the heater core/ supplemental rad mounted FWF. Works well.

I'd just use a standard ball valve if you want to restrict coolant flow somewhere. Cheaper and more robust/ reliable.

The heater core issue is a bit down the road for me but I do want to think it through and that helps. This engine actually has two bypass loops. I plan to put a heater core in one and duct the exit through the firewall for heater. Actually defrosting the windshield more than anything.

Charlie
 
Charlie- Nice looking package! Do you happen to know the design duty-cycle of this engine? (time permitted at full power, or % power permissible for continuous operation). - Otis

Otis, welcome to the thread, and thank you for the kind words.

Your question is a good one and yet it is also one that if I am not careful, will cause this thread to spin out of control over the endless (and not solvable) debate.

It is like answering where is the ark of the covenant buried?!

There are those out there who have a firm stance that "alternative" engines cannot be relied on to run for extended periods of time at high output settings (75%+). Others believe that they can operative for well over a thousand hours at high outputs settings. Both have some research to support their positions, but mostly it is anecdotal.

Obviously since I chose to use a Honda Civil 1.8L engine. I am in the later camp.

I hope that answers your question to a limited degree and I also hope that others will resist the temptation to jump in and try to use this thread to crack open THAT Pandora's box. I just want to keep this thread as a venue to share what I am doing, and keep it fun and friendly.

Thanks again for posting and welcome to the project.

Charlie
 
The highest stress on prop blades, propshaft, gearbox, coupler, crank, and engine accessory drives is unlikely be found at 75% or WOT. Nor will it be found at any static throttle position.
 
test fit with cowling

Here are two pics from the first fit of the engine in the cowling. The tough part for me was fitting this set up in a cowling that I made for a different engine. But, the good news is that it look like there will not have to be much modification for things to work out.

Nothing here is hooked up so don't be concerned about all the loose wires and hoses, etc.

Sorry for the hazy pic.

oW3.jpg


The turbo side. This will be the busy side. Turbo and exhaust, coolant tubes running down and around to a belly mounted radiator, and of course the outlet from the turbo that will be routed to the other side where the intake is....(and disregard the TB you see here. That will be routed lower to fit in the cowling.....

Lost to work on!!

oW4.jpg
 
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Another aspect I am considering is the use of a manual valve in the bypass loop, or the heater core loop.

They look like this.

oWg.jpg


Ross, do you or anyone out there have any experience with these... good or bad?

Seem like it would be easy way to adjust coolant flow, much like the purpose of the adjustable exit ramp after the radiator...

Charlie

I can comment on that valve. It looks exactly like the heater valve used on millions of Ford vehicles, decades ago, including my 1970 Bronco. They do not throttle, even though upon visual inspection it appears that they should. Heater is on if the knob (cable actuated) is off the stop. After that it doesn't matter if it's wide open or just a tiny bit. in 25+ years and a couple of hundred thousand miles of ownership I've been through a few of them. Despite regular coolant replacement they eventually rot out and spew coolant. If you choose to use one anyway, be advised that they are also directional. Some aftermarket valves have an arrow indicating flow direction stamped on them, but not all. Run them backwards and they leak.
 
Always an exciting part to put the cowling up and see how everything clears- or doesn't. Good to see the progress.
 
I can comment on that valve. It looks exactly like the heater valve used on millions of Ford vehicles, decades ago, including my 1970 Bronco. They do not throttle, even though upon visual inspection it appears that they should. Heater is on if the knob (cable actuated) is off the stop. After that it doesn't matter if it's wide open or just a tiny bit. in 25+ years and a couple of hundred thousand miles of ownership I've been through a few of them. Despite regular coolant replacement they eventually rot out and spew coolant. If you choose to use one anyway, be advised that they are also directional. Some aftermarket valves have an arrow indicating flow direction stamped on them, but not all. Run them backwards and they leak.

Thank you for sharing your results. I am still undecided on using it. It would have some advantages to have a valve in the heater core bypass, but I am also a fan of keeping it simple and not adding "things" that are not needed.

Charlie
 
Turbo remount

I decided to "flip" the turbo to fit inside the cowling better. I thought I would share this because some people may not know that the center section commonly calls the CHRA (center housing rotating assembly) and the compressor can be rotated, or "Clocked".

In my case, as in a lot of installations, how you configure the mounting of the turbo can include many different positions. All are a trade off. The main issues to work through are the routing of the exhaust pipes and of course compressor outlet pipes so it can connect to the intake. None the least is to also work out the best passage for the oil drain hose.

Here is a picture of the turbo flipped compared to the previous position. You can see from my previous photos this position lowered the turbo by several inches, created a better clearance from the cowling. It does make it a bit more of a challenge to route the exhaust and the drain tube, but overall I like this set up better. You can see that I had to weld up an a short 2" adapter so as the turbo bolt pattern is different that the Honda exhaust flange.

I have not re-positioned the CHRA and Compressor yet. That is to come..

oWQ.jpg


Charlie
 
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changing the mount plates to move engine up.

One of the advantages of the engine mount and plates of this design is the flexibility to move the engine a minor amount up/down/left/right without having to build a new mount.

Once I rotated the turbo 180 degrees (flipped it) it allowed for a lot of room above the engine overall. With this new room, it just made more sense to move the engine up almost an inch. While that does not sound like much, it will be quite beneficial in my case as it will allow me to do less modification to the cowl, especially around the spinner.

To move the engine up almost an inch, I just need to lower the points on the engine plates down an inch. Here is a pic of the top engine plate being re-drilled with the engine mount bolt holes relocated.

oWP.jpg


Notice the lower plate with the mounting bushings still in place. The lower plate mod will be next.

Also, one tool that is exceptionally handy at this stage is the use of a Center Point Punch. As you can imagine, it is critical to get the engine mount bolts holes drilled in the precise location. Fortunately you can get a set of center point punches at most hardware stores for a reasonable price. If you venture down the road to do a alternative engine installation they are a "must" have tool. There is just no other way that is easier and more precise to transfer patterns that this.

oWW.jpg


I will post pics when both the plates are done. One thing I know for sure at this point, I will also have to redesign the idler pulley mount. Not a big deal but something to accomplish. Those weird challenges are almost enjoyable to me.. It is a chance to tackle something new. If that sounds crazy to you, you are probably not one to take on a alternative engine installation project. If it sounds like something you would also enjoy, you are probably "wired" just right. :) for an alternative engine install....

Charlie.
 
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Those BMW donuts are similar to what Mercedes has used for several decades.
Also redrive from air trikes in Canada use those heavy, but strong couplers up
to 180 -200 HP !Tom
 
To all who are interested in this project for learning and not critizeing, I can personally tell you Ross cooling system is fantastic, as are his SDS systems. On another note I cannot understand cutting coupler at all, and as others have found out, a stock flywheel , thou some are heavy, a 4 cylinder anything is very happy with. Lite or no flywheel does not make sense to me at all. Tom
 
Those BMW donuts are similar to what Mercedes has used for several decades. Also redrive from air trikes in Canada use those heavy, but strong couplers up to 180 -200 HP !Tom

Couplers are engineered with specific properties. They have been used successfully in thousands of different applications, and properly applied, they are excellent. However, picking the wrong one is just another fail.

Here there is no property application available. It is impossible to do torsional design without the data, and none is available for the BMW coupler. I wrote the manufacturer and asked.

However entertaining, there is no point in watching it be done wrong again.
 
To all who are interested in this project for learning and not critizeing, I can personally tell you Ross cooling system is fantastic, as are his SDS systems. On another note I cannot understand cutting coupler at all, and as others have found out, a stock flywheel , thou some are heavy, a 4 cylinder anything is very happy with. Lite or no flywheel does not make sense to me at all. Tom

I agree. While this setup does not use a flywheel, I can tell you the rotating mass of the components of the PSRU, coupling, and prop and flexplate all together are very important.

I could not agree more about the cooling scoop/system that Ross shared on his SDSEFI website. It saved me a TON of hours of contemplation and research. I hope I can be on that part of the project real soon. I don't have the desire to make mine as beautiful as his with hundreds of hours of shaping, sanding, a wood/fiberglass set up. Mine will be more utilitarian metal. I made a 24" Break last weekend to bend the sheets .032 aluminum for the scoop.

I also got the radiator in the mail today. While looking for the right radiator and talking with a local shop about making a custom unit, I found out that a Honda M/C CBR 1100 was so close to the dimensions I needed that I decided could not pass it up, so I ordered one. I think it will work out well, and they are plentiful and as such very reasonably priced.

Lots to post in coming weeks.

Charlie
 
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Radiator

Below is a picture of the radiator I am seriously considering using for the under the belly scoop (like Ross from SDS). Arguably you can consider this somewhat akin to the P51 concept.

As you can read in the pic this is what is used on the Honda CBR 1100 M/C. They are readily available on the "net" for less than $100.

It is not exactly as wide or as thick as would be ideal, but all things that I know, this should work out OK. I also plan to use a fairly generous heater core up front in the cowling on one of the two bypass loops which will also help provide some cooling.

oWJ.jpg


One issue that I will debate while building the scoop is to "tilt" the radiator to lower the profile. While I completely understand it does negatively affect the airflow, as thin as this core is, it won't be as much as if it was a 3" core. If it it was that thick I would not even consider a tilt. This is in the yet-to-be-decided category.

( updated - I end up not using this and went with one that was shorter and wider...…-CR)
 
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I wouldn't consider tilting it. Any reduction in frontal area scoop drag will be likely offset by increased drag within the duct. If you look at the angle required to actually reduce the frontal area given the depth of the core, you'd have to lay it down a lot. This makes it harder to mount as well.
 
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Ross,

I do agree "tilting" is not ideal, especially as it relates to the direction of the airflow, and knowing the radiator I am considering, it is only 1.2" "taller" than what is ideal, it would be easy to remove an inch for a better (reduced) frontal footprint.

I remember your write up, you made sure to avoid angles that are greater than 7 degrees. This is consistent with what I have read in various other articles. I also agree that ideally tuft testing for laminar flow is very helpful, and if I remember correctly in your case this helped you to learn that adding a sheet to direct flow to reduce separation and get more laminar flow.

Thanks for your willingness to share your experience.

I do plan to create a cardboard mock up and see what I like, as well as see how well things go together and of course, how much I can keep it simple but effective.

Charlie
 
Check with various race stores for shorter/wider radiator,as will make mounting/ plumbing easier ! Tom

Tom,

Thanks, I agree, and I have spent considerable time on research and various mod shops like Jegs, Summit etc....I do see how wider and shorter would reduce how much you see from a side view under the belly...but I don't see how it would make the install any easier....

We do have a very reputable radiator shop in town that does a ton of custom work and they have not found anything closer than this radiator. Based on the numbers (below) I can't see the benefit of having a custom one made...... at least not based on what I know now....

If my notes are correct, here are the numbers that Ross has shared on his set up:

119 in2
267 in3

And I believe his engine produces considerably more HP than I expect I will ever get close to. And based on what I remember reading on some days his set up over cools to the extent at times has to reduce the intake opening as it cools too much. (Ross please correct me if I got this wrong).

This set up currently has:

143 in2
230 in3

I am good with those numbers...

Charlie
 
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I'm making about 160hp on takeoff at 35 inches.

The rad numbers are correct but I also have a 54 in2/ 88 in3 heater core plumbed in the thermostat loop which is active at all times and fed by a round, 3 inch ram tube below the spinner.

Extended ground idle and climb are your big cooling challenges on hot days.
 
Ross,

I appreciate the numbers on the cooler on the bypass loop, I was wondering what size it was. I plan to do the same.

Are you using a oil sandwich cooler? If so what size cooler on it?

I also found another radiator and a professional sheet metal guy who is willing to chop it for me for next to nothing so the other one would have a core that is 20" wide, and 2.2" thick. I would probably cut it down to about 7.5" tall.

Not a huge difference but maybe enough to avoid some high temp on the hottest days....like waiting for TO at OSH!

Charlie
 
Yes, I use a Mocal sandwich plate with oil thermostat and a large Earls cooler. This lets the oil warm up quickly and handles the oil temps nicely in a long climb. The turbo adds a lot of heat to the oil compared to an atmo engine.

On the Subaru, due to the proximity of the oil and coolant passages, oil and coolant temps are heavily tied to each other.

Yes, if going to Osh or anywhere with long holds, you need to be able to dissipate heat from the coolant almost indefinitely.

I'll measure the cooler next time I have the cowling off but I'd estimate it's about 9 X 9 X 1.25 inches
 
Ross,

Good to know. Hate to pepper you with all the questions, but do you feed the oil cooler with a blast tube? I am sure I saw scat duct on your heater core.....

Charlie
 
Now that I have the mount done, the cowling on, the turbo flipped, and the decision made to install the main radiator under the fuse.....it is time to get serious about "plumbing" and routing.

I need to find a home in the cowling for the:

1) Intercooler. Looks like this will be "inside" the engine mount. The cool air duct will probably be from a naca inlet in the bottom of the cowl.
2) Heater core on the Bypass loop. Looks like this will fit just inside the left inlet.
3) Oil cooler. Not sure yet. I might be able to snake hose from the right inlet but I need to do other work first.
4) Exhaust. This will loop 135 degrees to angle down outside the bottom of the cowling about mid way.
5) Route the coolant lines to the belly radiator.
6) Clock the turbo and create new oil feed and drain lines. These will have to be redone since I flipped the turbo.
7) New mount for the Throttle body. Which of course means new linkage too. Fun....

If you are new here and wondering that this all looks like the last few pics of the engine in the cowling are on post 267...

This should keep me busy for a couple of days. :)
 
The NACA duct isn't a good choice to feed heat exchangers, especially a thick one like a typical intercooler. A ram duct will be far more effective if you have a place to fit that in.
 
The NACA duct isn't a good choice to feed heat exchangers, especially a thick one like a typical intercooler. A ram duct will be far more effective if you have a place to fit that in.

Yes for sure. I certainly am open to that idea, I would think that a 2" opening would be more than enough (considering it is ram air up to 160+ mph) (?)...and the bottom of my cowl slants downward so it really does lead well to doing this. I might try to create a mock up using PVC pipe of what just crossed my mind to see if this is what you are thinking.....(Essentially having a 2 inch tube protrude a very slight amount and glass it in...)

Charlie
 
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Yes for sure. I certainly am open to that idea, I would think that a 2" opening would be more than enough (considering it is ram air up to 160+ mph) (?)...and the bottom of my cowl slants downward so it really does lead well to doing this. I might try to create a mock up using PVC pipe of what just crossed my mind to see if this is what you are thinking.....(Essentially having a 2 inch tube protrude a very slight amount and glass it in...)

Charlie

I doubt if a 2 inch round duct would provide the required air and you'd need a very efficient diffuser to wet the whole HX surface efficiently.
 
Based on some early design ideas i do think I ll be able to get the air flow coming at the face of the heater core and intercooler.

There's always a trade off. Either bends in the supply routes or bends in the cooling tubes, but rarely are both sets straight.

I know the goal is to work on the design to get the most fresh air there with as few (sharp) bends as possible. And... without compromising the supply lines.....
 
The bigger concern is that a 2 inch round hole only has an area of around 3 square inches and you won't get the same mass flow as my inlet which has about 17. 17 may be overkill but pretty sure 3 isn't nearly enough. Climb is where you'll see most oil temp issues where your mass flow is about half of what it is at 160 mph.
 
Sorry I may not have been clear. I'm leaning towards a ram air for the intercooler. The left nose inlet for the heater core and a separate dedicated ram air for the oil cooler. Sizing of ducting TBD...
 
Sorry I may not have been clear. I'm leaning towards a ram air for the intercooler. The left nose inlet for the heater core and a separate dedicated ram air for the oil cooler. Sizing of ducting TBD...

Depending on compressor efficiency, boost and altitude, the heat load of the intercooler can be substantial and you'll need a fair size duct feeding that too. I was way too small on that initially. I eventually re-positioned the intercooler and tripled the size of the duct feeding it. IATs all good now.
 
I got the heater core yesterday. This is what I plan to use for the bypass loop. This one has a core that is 9"x6"x1.5". It is a heater core from the CJ series of Jeeps.

The pics show it held up front behind the left inlet of the cowl. It fits very nice there. But if i moved it to the right side I could dedicate the left side for the intercooler, which would save me the need punch a hole in the bottom of the cowl for a new ram air source for the intercooler. The only problem is the right side of the cowl is really busy and squeezing even that small heater core will be a challenge.

o1R.jpg


o1Y.jpg
 
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Belly radiator in progress

Here is a look at the newer slightly larger main radiator that will go under the belly. I opted to go with it instead of the Honda M/C CBR 1100 radiator because it was slightly bigger. The Honda was about 200 Cu In, and this will be about 290 cu.in. Since they both had to be cut down, I figured might as well go with the one slightly larger. Plus at 24" wide this just happens to be the right width for me to be able to capture the angle aluminum in the belly which will be a good place to rivet to.

This is in the cut down stage prior to being welded.

o1r.jpg


This pic below gives a better view into the cut off section. I used a metal blade on my table saw, which does an excellent job of cutting it. the top part of the core is actually a coolant tube that I split with the table saw blade. I will reinforce this with a 0.125 bar of 6061-t6 as well as cap off the side tanks. The tanks were much larger than I prefer at 2.75" square, but not so large I was interested in cutting them down. It calcs out to about 4.3 lbs of water in the side tanks so not real bad...

o1w.jpg


One thing you cannot see it the filler cap that I cut off and this will be closed off with 0.125" 6061-T6 as well.

Charlie
 
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new rendition of the throttle body location

I thought I would show my newly modified TB mount. It is in the mock up phase and I hope to have it welded by Tuesday.

P.S. I cut 1/4" and 3/8" aluminum plate on my table saw with a non-ferrous metal blade with no kerf. These are common in the aviation section in Lowes or HD. Works great!

o1G.jpg


It will go where the intake variable length runner motor/actuator usually live. I took it out. Not beneficial for my needs. ''

There is no free lunch. I spent a lot of time last weekend trying to find the best home for the intercooler and after much trial and error it will live within the engine mount. I will dedicate the 4" line straight from the left nose inlet for it. I do believe it will work well.

I still plan to put the heater core up front on the right side and probably run the oil sandwich coolant lines over tot he left side and feed it from a naca duct.

The real challenge will be getting the main coolant lines to the belly radiator and of course build the belly scoop .

Lots more coming in this thread soo.
 
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Exactly one year milestone - and 36,500 views!!!

Tomorrow will be the 1 year anniversary of this thread. Considering it logged over 36000 views is really remarkable.

For a variety of reasons there are a lot of people interested in this project, at least conceptually. I just don't think it is very common to average 100 views a day for a year, for a simple project like this.

I hope this encourages others to be willing to share their ideas and projects, even if it includes an alternative engine for power.

I also hope we can learn from each other, remain respectful, and just sit back and enjoy the process.

I truly appreciate all the words of support and encouragement.

Much more to follow...

Charlie
 
Tomorrow will be the 1 year anniversary of this thread. Considering it logged over 36000 views is really remarkable.

Continued best luck... I've been following your progress for several months. Wish I lived closer so I could come and take first hand look.
 
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