Small Turbo oiling questions

[Chaulkdust]

In my on going attempt at creating a small displacement turbo bike for LSR I have finally made enough progress to start on the turbo. The bike is a 1966 CB160 Honda that has been bored out to 174cc’s, with the appropriate new components (pistons, rings, valves, gaskets etc). The bike is now running great in it’s non-turbo state. My plan is to install a IHI RBH31 turbo (really small) blow through setup, but since the little CB160’s oil pump won’t supply enough PSI for the turbo oiling function, I planned on an external oiling system. Had a couple of questions about the oil plumbing. From what I’ve read and researched so far it seems like I need a -3AN line to the turbo oil inlet from my external pump. I’m having a devil of a time finding the 3AN fittings, hose, and check valves seems like 4AN is the more common size available? Just wonder if I can use 3AN brake hose for my oil input line, which seems easier to come by. Could just use a 4AN line & fittings with a restrictor if needed. Anyway, since this my first attempt at the turbo setup thought I’d try and get some suggestions. If this isn’t the appropriate place to post this please direct me to the appropriate location.

Ron Pavlak

[Dakin Engineering]

I run an IHI RHB52, and have used brake line.
What are you using for a pump?

Sam

[Chaulkdust]

A Shurflow pump.

Ron Pavlak

[Chaulkdust]

Sam - I had to check, but it is model 8000-643-236, rated to 180 deg F, Buna-n Valves,  Geolast & Buna-N Diaphragm, max 60 PSI.

Ron Pavlak

[moirmyster]

hi im in the same procces of fittting a turbo to my xr200,i guess it has the same bottom end as the cb160,that is my bigest problem,not to sure if enough oil pressure from the engine.
How are u getting on with yours chaulkdust,what hav u come up with.
Any sugestions from any one would be cool.

[generatorshovel]

I use a small CB125 bottom end with my project, and part of my testing was oil flow / pressure.
The stock Honda oil pump has all the flow you need, but as the bottom end  uses a roller bigend bearing,and rollers in the 'box, high pressure will never happen.
I'm using a yamaha slipper bigend now, and after completely re-routing the oil flow, have pressure relief valve set at 50 psi, so the pump has the potential, you just have to split the flow, regulate the pressure, feed it to your turbo , then dump low pressure bleed of thru your engine.
Tiny

[moirmyster]

thanks for that tiny,so i was thinking off fiting a brake line fitting to top of the head stud where oil comes out,then to the turbo then the return back to the engine,does that sound like it would work.does the turbo need much pressure.

[Jonny Hotnuts]

I don’t know the little motor but you may have problems. I could see that by tapping a line off the head stud you could decrease the amount of oil pressure to the cam bearings. I am almost 100% sure that the reason you should run smaller line is to maintain pressure on the backside. This means that you should be able to run any size line you want.....as long as you have a flow restrictor.

Originally I was going to run 1 motor (now we have 3). I came up with an idea to use a small oil cooler and pump to supply the turbo with oil 100% separate from the motors oiling system.

This way I could easily remove the plenum, up pipe and turbo body and run in the NA class in about 30 minutes.

For whatever its worth....if you are already going to have an electric pump, with a small reservoir and oil cooler could very well mean you could leave the motors oil alone. (you could also be able to pull the system and run NA on the same bike as well without having to screw with the oil lines).

*BTW- this idea may be terrible....I dont know.

-JH

[Dakin Engineering]

I use Clark Solutions MG209XPB17 pump with a MGC4 12VDC motor. Magnetic coupled, internal pressure relief and adjustable output pressure. 5W 15 syn in a closed loop. Neat.

Sam

[Chaulkdust]

Jonny summed it up very nicely. What he said is very much what I’m doing on the CB160. I’m using an external oiling system with pump. I have a modified car oil catch can as my turbo oil reserve. I’ve mounted the turbo high up front with the reserve below for direct drainage. The pump is mounted in front of the rear wheel on a plate in back of the battery. I used -6AN lines from the reserve to the pump, from the pump to the oil cooler, -3AN lines from the oil cooler to the oil pressure guage (1/8 npt fitting) to the turbo. Still a work in progress, hopefully I’ll run at Maxton next June. I’ll try to get some pictures posted.

[Chaulkdust]

CB160 some pictures

[Chaulkdust]

CB160 More Pictures - I think I figured out how to do this.

[Chaulkdust]

Another Batch of photos

[Chaulkdust]

Last group of Cb160 pic's

[McRat]

Might be a tech problem.  You probably already know.

If you feed boost in the front of slide carb, you can force the slide up to the top (WOT) and it won't go back unless the boost falls.  At a minimum, I'd like a "push-me-pull-you" style slide carb instead.

You can put a vent hole up top and run a boost line to it?  Your floatbowl vent must be fed boost too.  Personally I like the carb in front of the compressor.

That is the cleanest CB160 I've ever seen.