60PS Turbo Charged RC390

Ryanthegreat1

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That would probably work. 60hp is about 6lb/min of air. That is right in the fat of the compressor map for the RHB31 turbo they used. That would be about 9psi of boost, seems reasonable. I wonder what the spool time is like.

And with the turbo mounted so low I am curious about how well the turbo oil drainage works.

Edit: I see on the R3 they have an oil pan spacer. No such spacer on the RC390 that I can spy. I wonder if that oil screen on the front of the RC390 is the scavenge pump and you could make that drain bolt an oil return from the turbo. Then the oil would be scavenged out of the turbo and no worries about blowing oil into the turbo.
 
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Fasteddy

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Yes, front small screen is input to suction / scavenge pump, left side bigger screen is between suction and pressure pumps then off to the oil filter...
I was looking at the lubrication system in regard to oil cooler discussion, with out metering of flow through the oil cooler I think it would be detrimental to the rest of the system and with the flow to the oil cooler cut down why bother, but, a turbo would not need to rob too much flow from the system. Out the oil filter cover through turbo / meter jet in the front screen...

I did not even see a oil line going to the turbo on the RC in the pics, it just looked like a blocking plate...
 

Ryanthegreat1

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I think the block off plate is for the water jacket on the turbo center section.

Here is the water manifold that would bolt on there.
Water Cooling Tube for Mini turbocharger VZ21 IHI RHB31 Turbo | eBay

What is more puzzling is the lack of wastegate actuator. You can see the pivot for the internal gate sticking up and it has nothing on it.

Even on the R3 version the wastegate actuator is just hanging out there in the breeze.

Yamaha-R3-Turbo-KTM-RC-390-Turbo-27.jpg

Here is the RC390 with the arm of the internal gate removed and just the nub of the pivot hanging out.
Yamaha-R3-Turbo-KTM-RC-390-Turbo-24.jpg
 
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Fasteddy

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Thanks for the link, I am lagging behind in turbo tech (pun intended) I did not know that thing was water cooled, I did note the lack of waste gate and figured they probably can get away without it by keeping tunning under control, or carrying spare head gaskets! I would assume they would cut a copper bead seal into the head to control the pressure and mill the the piston???
 

Ryanthegreat1

New Member
For 9psi a normal MLS head gasket should be adequate. No need to get fancy with fire rings. But we have not exactly got a great track record with the stock head gaskets.

I guess you could run with the wastegate welded shut and just use the turbine housing choke line as your boost control. Seems like a poor idea because the compressor map goes to ~15psi before it hits the choke line. It could work I guess, kind of hard on the turbo.

Using the turbine choke limit would probably send the EGTs through the roof as well. And create a lot of EGR and lead to detonation at the worst time.
 
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Fasteddy

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Maybe pics were more for show? not ready for prime time, I have been looking at that turbo on google pics some interesting projects with it. Turbo Ruckus, Turbo Vespa etc...
 

ritz83

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this bike has also been created with the help from my dealer and his mechanics :) I live in Padova in Italy. I have seen and heard live .. a monster. I am talking to the workshop boys were spoken to me that they were about making final arrangements because they want to create it with road homologation kit (at least in Europe, do not know the U.S.A. directives if they are equal)
 

psych0hans

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The biggest question is how it will fare on a track... I'm not sure turbos are ideal for track usage, but I could be wrong.
 

cjwell

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60 PS is more than that engine will take for long. I'm on the threshold at 50 hp... The I built the turbo Diavel making 235 hp and 130 ft/lbs of torque on 10 psi. That was a job. I like turbos, hats off to you. Just watch how much boost you throw at it for longevity reasons. I've torn up plenty of parts at 50 hp :p
 

Ryanthegreat1

New Member
What parts are you breaking at 50hp? I seem to remember something about valve spring retainers.

The thing I really like about turbos is they don't raise peak cylinder pressures that much but they do raise the mean pressure a lot. So they are rather gentle on engine parts until you start hitting knock and heat limits.
 
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TheRoadWarrior

New Member
What parts are you breaking at 50hp? I seem to remember something about valve spring retainers.

The thing I really like about turbos is they don't raise peak cylinder pressures that much but they do raise the mean pressure a lot. So they are rather gentle on engine parts until you start hitting knock and heat limits.


if the engine and tuning is solid, its usually other things that start to go.... transmission and driveline parts that were not designed to handle 50% more than the stock power


that being said, i would TOTALLY grab this kit if the price is reasonable.... i love the look, size, feel of the RC390 for zipping around town, its just lacking power (and it sounds horrible)... a turbo would fix both those problems.

id imagine if youre driving it only on the street semi-casial with a little bit of fun like i am it should last for awhile.... beating it up at the track going max effort is probably gonna break some stuff fairly quick
 
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