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  #61  
Old 07-30-2018, 08:07 AM
sorry dog sorry dog is offline
 
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Wonderful project. I am thankful that there are others out there that are tinker minded and put the experiment in experimental.

I am wondering why the R18 was chosen instead of the R20. Wouldn't the R20 be a free 10 or 15 hp for little or no weight penalty?

Is it cost, availability, technical, or some other reason?

Thanks again for sharing.
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  #62  
Old 07-30-2018, 03:29 PM
pr1malr8ge pr1malr8ge is offline
 
Join Date: Oct 2014
Location: NW Indiana
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I've been looking at this thread on and off since it's inception.

I had my thoughts on how Honda engines would fair with being put into this type of situation. More specifically I was wondering about the VVT and how it would be, it seems that this is an issue. I wish the OP the best of luck in this en devour and he may over come those issues.
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  #63  
Old 07-30-2018, 06:19 PM
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charosenz charosenz is offline
 
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Location: Longview, Wash
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Quote:
Originally Posted by sorry dog View Post
Wonderful project. I am thankful that there are others out there that are tinker minded and put the experiment in experimental.

I am wondering why the R18 was chosen instead of the R20. Wouldn't the R20 be a free 10 or 15 hp for little or no weight penalty?

Is it cost, availability, technical, or some other reason?

Thanks again for sharing.
Dog,

Thank you and great question on the R20. They are viftually identical, with a few exceptions. The R20 having a longer stroke of course. Also it has a counter rotating shaft to offset additional rotational vibration that very long stroke induces. Both are great engines in my book. I chose the R18 because it is slightly lighter (I am not sure how much), and more importantly, there are more R18 in production, I.E. in junk yards. There are a few more minor differences as well. Either would work great, imho.
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  #64  
Old 07-30-2018, 06:31 PM
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charosenz charosenz is offline
 
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Location: Longview, Wash
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Quote:
Originally Posted by pr1malr8ge View Post
I've been looking at this thread on and off since it's inception.

I had my thoughts on how Honda engines would fair with being put into this type of situation. More specifically I was wondering about the VVT and how it would be, it seems that this is an issue. I wish the OP the best of luck in this en devour and he may over come those issues.
Thanks. Good to hear. It is important for readers to know that VVT and V-Tec ( or i=Vtec) are quite different.

The VVT has to do with variable or adjustable cam shaft gears. This has been been widely used in(primarily) older honda engines and is designed to create additional power at higher RPM in many Honda, but NOT, the R18 or R20.

The R18 and R20 use i-VTEC which is quite the opposite. (see more detail in previous posts in earlier posts in this thread). But in short, i-Vtec uses an oil control (spool) valve to activate the cam lifters between the default "power" lobes or when it senses a low load it activates the lifters to have the "economy" lobe profiles.

In my case I simply hard wired the spool valve so it would presurize the lifters to always use the "power" profile cam lobes.

Charlie
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  #65  
Old 07-30-2018, 06:42 PM
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charosenz charosenz is offline
 
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Originally Posted by BillL View Post
What was the internal failure? Pistons or valves? Failures tell us what is weak. Keep the progress coming.
Bill,

Good question.

It was primarily my stupidity for not watching the plugs close enough during testing. I mistook that stumble at 5000 rpm as the engine "missing" when it was really pre-ignition. It did not have that tell tale typical sound to me.

I could have reground the cylinders, but when these engines are only $550 with less than $20k miles on them it was an easy choice to just get another one.

Hope this helps.

Charlie
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  #66  
Old 07-31-2018, 12:25 PM
BillL BillL is offline
 
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Originally Posted by charosenz View Post
Bill,

Good question.

It was primarily my stupidity for not watching the plugs close enough during testing. I mistook that stumble at 5000 rpm as the engine "missing" when it was really pre-ignition. It did not have that tell tale typical sound to me.

I could have reground the cylinders, but when these engines are only $550 with less than $20k miles on them it was an easy choice to just get another one.

Hope this helps.

Charlie
Charlie, I was not implying that you did the wrong thing. That engine is 10.7:1 compression ratio, meaning that any boost will amplify combustion issues. A teardown to see what how things fared would be revealing. If the PI just burned a hole in the piston, but the rings and skirts stayed cool enough not to gall, then that shows good cooling. If the rings stuck and then skirts galled along with the crown melting, then one might still be concerned about overall piston temperatures even with desired heat release. This is why I asked. Auto engines running under full power for hours will exhibit different failure modes than short dyno runs. or race car engines. It's not that auto engines (in general) can not be used in aircraft, but the weaknesses must be revealed for correction before they affect people. Either super instrumentation or teardowns with some careful test progression are needed to do that. Teardowns would be suggested simply to understand the health of an engine as it progresses to flight configuration. Repairs are not necessary. Many other parts can be inspected in a teardown. (like bearings, wrist pins, etc)
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  #67  
Old 08-04-2018, 09:54 PM
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charosenz charosenz is offline
 
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Quote:
Originally Posted by BillL View Post
Charlie, I was not implying that you did the wrong thing. That engine is 10.7:1 compression ratio, meaning that any boost will amplify combustion issues. A teardown to see what how things fared would be revealing. If the PI just burned a hole in the piston, but the rings and skirts stayed cool enough not to gall, then that shows good cooling. If the rings stuck and then skirts galled along with the crown melting, then one might still be concerned about overall piston temperatures even with desired heat release. This is why I asked. Auto engines running under full power for hours will exhibit different failure modes than short dyno runs. or race car engines. It's not that auto engines (in general) can not be used in aircraft, but the weaknesses must be revealed for correction before they affect people. Either super instrumentation or teardowns with some careful test progression are needed to do that. Teardowns would be suggested simply to understand the health of an engine as it progresses to flight configuration. Repairs are not necessary. Many other parts can be inspected in a teardown. (like bearings, wrist pins, etc)
Bill,

No mystery on the lost of compression on two cylinders, it was my error for allowing pre-ignition to happen largely because of way too much advance, and a few other issues, like too lean AFR settings. A lesson learned.

In other words it is not the engine, and certainly not the 5 lbs of boost. It was "pilot error".

The good news is that this is all happening on a test stand in my parking lot, and there is a lot success happening, and of course an occasional set back once in a while, just like with all projects, right?

The parts.....there was galling on the piston sides and some scuffing on the cylinder walls, and the rings were in poor shape. The piston tops and head domes were all in good shape.

Ill be adding all those solutions that I listed a few posts back.

Ill also be testing water/meth injection - hopefully tomorrow. This is an often overlooked very simple solution to reduce IAT. Once I have completed that testing, I will add an intercooler. But I am purposely taking things in steps to verify if there are advantages or not.

Charlie

Last edited by charosenz : 08-04-2018 at 11:05 PM.
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  #68  
Old 08-05-2018, 01:46 PM
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charosenz charosenz is offline
 
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Default Things looking great

Good success with the addition of the solutions I listed earlier.

I transitioned through 5200 RPM at 35" MAP with breeze today.

I added water/meth injection but I developed a leak in the pressure gauge connection so I did not use it long. My initial impressions are that it dropped the IAT 10*F. This is with only a M1 nozzle which is very small. A lot more to play with on this concept. There should be more like a 20* drop if things are set up correctly.

I suspect there may be some water being sucked in to the intake at high vacuum settings so the temp results may be skewed. A lot of people add electric valves to prevent this, but I am a fan of keeping things simple so I wont add that until I am sure it is needed.

The most important to me is that there was no hint of stumble or miss, or preignition at all and this validates the list of solutions I previously identified. Anyone who may want to venture out on a project like this should do the same.

I am hoping for 40" at 5000 rpm and right now I can only get 35" at that RPM. I am at 19* pitch on the prop, and I can add more but I think much more and I will be past the point of the prop being efficient. It is only a 68" 3 bladed tapered warp drive prop. Great Prop, I love it, but I might need a 70" or 72" prop to get me at the settings I want to be at.

I do have a bleed valve on the turbo wastegate, and I plan to do some air bleeding, but I suspect without more prop pitch or diameter, this will only increase RPM......

I encourage others to chime in here and offer thoughts.....

Charlie
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  #69  
Old 08-05-2018, 04:37 PM
BillL BillL is offline
 
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Quote:
Originally Posted by charosenz View Post
The parts.....there was galling on the piston sides and some scuffing on the cylinder walls, and the rings were in poor shape. The piston tops and head domes were all in good shape.
Not a setback at all, just part of the development process.

From my experience, if the crown was not melted, then it is a deficiency of skirt cooling. Obvious, but it would mean the piston cooling jets might need to be enlarged.

It is typical in heavy duty engines to see a skirt failure with a cooling jet problem. Just something you might want to adjust in this engine for continuous high power.

Actually, this is a good indicator for the strength of the piston crown!!

Keep up the reports!
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  #70  
Old 08-05-2018, 08:22 PM
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charosenz charosenz is offline
 
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Quote:
Originally Posted by BillL View Post
Not a setback at all, just part of the development process.

From my experience, if the crown was not melted, then it is a deficiency of skirt cooling. Obvious, but it would mean the piston cooling jets might need to be enlarged.

It is typical in heavy duty engines to see a skirt failure with a cooling jet problem. Just something you might want to adjust in this engine for continuous high power.

Actually, this is a good indicator for the strength of the piston crown!!

Keep up the reports!
Bill,

The engine is one of the most advanced featured and turbo friendly engines on the market and it would be crazy for anyone to alter any of the internal components. The only error was on my end, certainly not the engine.

It is running excellent now with steps I listed a few posts back.

Here is an excerpt from Fullrace.com that highlights some of the advanced features on the engine. I think you and other readers will find this very informative.


Top 10 things that make the R18 perfect for boost.

ultra-lightweight engine, and transmission, showing cylinder head with integrated manifold.

Bore and Stroke are identical to the legendary GSR and ITR B18
The R18 uses a full 1-piece main bearing girdle

“Long-rod” Forged Steel Connecting rods with rod BOLTS (not studs – easy to upgrade to ARP hardware)

The R18 has a 10% reduction in friction from a special cylinder wall hone and moly-sulfide bead blast and ion treated piston rings. High durability and low friction.

Pistons cooled by built-in oil jets (typically only found on high end Honda motors). This is important for a turbocharged engine which has increased piston temperatures.

Cylinder head design is an ultra efficient way to deliver high temp exhaust gasses immediately to a turbocharger

Easy to disable EGR using OE Honda components

The R20 is available for more power and any R18 guys looking for BIG power can do a bottom end swap to the R20 (or sleeve your R18 to 2.0L!)

Hondata FlashPRO is available!! MAF based engine management makes tuning very accurate and simple.


I agree with you, all I have learned about this engine, is that it is very well designed and an excellent choice for my project.

Charlie

Last edited by charosenz : 08-05-2018 at 10:00 PM.
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