4-stroke engine
 

Ok, I'm not aure if this is the right place or not.

I need to get some info on a 4-stroke nitro RC plane engine. the good the bad, maintance, how long do they last, what kind of temps to run it at, basicly anythin and everything. I run nitro cars, but I look and modded one to fit a 4-stroke plane engine.

so any help you'll can give would be great.

RE: 4-stroke engine
 

and ringed and ringless engines, which do you prefer? what the ups and downs on the two?

RE: 4-stroke engine
 

I wouldn't think that a four stroke would make a good car engine because you couldn't mount on of the big heatsink heads on it. Cooling would be a real issue I would think unless you had some sort of fan arangement to keep a steady flow of air across it.

Power wise and realibility wise, they are great. They won't crank the high RPMs that the 2 strokes do, so again that may prevent it from being what you want. 10,000 it a rough rule of thumb on them. Just like a real car four stoke, if you run to fast, the valves well float and then who knows what might happen. I have a 70 Magnum that will run up to 11,000 but I detune it to top off at 10,000. My smaller 52's are good for 9800 to 10,500 depending on the props used. The four stroks have good low end torque so acceleration is good with them.

Don't know if this answered your questions, and I'm sure someone out there has a better prespective than I do on using them in a car.

Don

RE: 4-stroke engine
 

here a video of a car with a plane engine in it http://youtube.com/watch?v=IFTvObTPaQI that somthing like waht I want to do

how many gallons can you get out of one, do you have to shim the valves, what do you have to do as far as maintance, basicly I know nothing about fourstrok engines, and need to know everything or atleast as much as I can. so is there like a FAQ thread or somthing that tells all this?

RE: 4-stroke engine
 

This is the only one I know of specifically designed for cars.
http://www.osengines.com/engines/osmg2091.html

I seem to recall reading somewhere in RCU that they were easily modded for more HP but I don't remember any details.

RE: 4-stroke engine
 

They have a long life in a airplane, where cooling air is abundant. OS made two fourstroke models for kyosho cars and they used small belt driven fans to engine temps under control. The OS car engines were based on airplane engines but had high RPM cams and much stronger valve springs to keep valves from floating during high revs. This is where you are going to have problems with a airplane engine, when your car drive train unloads and rpms skyrocket, your engine will be damaged. This rarely happens in a airplane because even a small prop will still load the engine enough to keep the engine from completely unloading.

If you are going fourstroke, you should at least look for one of the OS fourstroke car engines because they are better suited for the punishment of a car.

RE: 4-stroke engine
 

You could use a regular airplane four stroke, if you pay attention to some details. First will be cooling. Second will be gearing. Gearing will be important to prevent damage from over-revving the engine. Like the guys say you can damage an engine by floating the valves. Most OS engines are non interference engines and will not bend valves. By gearing it appropriately the revs will be kept in check. The biggest problem would be making a clutch work with the supplied shaft.

I have both the OS 26 and 40 four strokes in car versions. The 26 is little changed except for stronger valve springs, a different cam, short stubby crank, straight intake manifold, and a modified crankcase breathing arrangement. The springs, crank, and cam are available through Tower, so theoretically if you couldn't find an old stock FS-26S-C or FS-30S-C you could make one from the airplane engine. The FS-40S-C has all the above changes plus larger valves than the airplane .40.

This is a thread I started a while back. It contains a link I found on the FS-26S-C.
http://www.rcuniverse.com/forum/m_5482581/anchor/tm.htm

Saito has also produced a car version of their FA-30. I've never seen it, nor a catalog listing for it.

RE: 4-stroke engine
 

Ok, I do know over reving will kill a fourstroke. My Dad has a CRF450R, its a 4-stroke race bike and that engine will turn 12,000-13,000rpms and reading on it, I always heard DON'T OVER REV" so I do know about the valves flowting (sorry if my spelling is of or bad, I don profread any thing on here.)

and as far as cooling, I plan on make a fan that will run off the engine's rpm's, kinda like a supercharger would, gearing I know I'm going to have to gear that thing aLOT.

I'll I need to know is stuff like tuning, maintence, how many gallons, (just a ruff amount) what temp the engine should be ran at, ringed or ringless, do I have to check the valves, or shim them (like my Dad's bike) and when I rebuild a 4-stroke engine, do I have to replace the piston, sleeve, piston ring (if there is any) and con-rod?

RE: 4-stroke engine
 

There is a new player now in car engines davis diesel has converted the ST28 to diesel. it is on you tube at diesel st-1. the advantages are they run cooler, very good fuel econony
fast response, lots of torque and more power output, a 28 diesel conversion is equilvant to to at least a 35 glow maybe 40. I do believe this is past the RandD stage. appears to be less hassel , no glow plugs . it is of course 2stroke the VP 21 4 strk may be uo to a 25 now Mecoa, but not a barn burner ditto for OS, I am not getting into the 2stk.vs. 4stk debate
The one thing they have in common of course is fuel economy martin


\One big advantage of the diesel is since they run cooler less issues with this

I missed Gregs post on this so looks Like he has done it. intresting enough he just converted a Mag52 4 strk to diesel for me but it is slated for aircraft use, my knowledge of RC cars is limited had a traaxax 12 years ago, but I am getting the ST truck with the diesel from Davis to mess with

RE: 4-stroke engine
 

Tuning the carb is the same as any other engine. You might get detonation if you go too lean, but unlikely in a .40 or smaller. Gallons of fuel? Just whatever it uses? Life, pretty long. Though, I think you would see less life in a car. Maintenance: adjust valves after break-in and occasionally after that, do a search in this forum, it comes up almost daily, and after-run oil in the crankcase for an airplane version. Engine temperature same as a two stroke, 200-280°F at the head. Rebuild: New ring and liner for an OS, new ring and cylinder jug for a Saito. All current production four strokes are ringed, except the OS FL-70. ASP supposedly made ABC four strokes, but I have never seen one except as a catalog listing. Replace parts as needed.

http://www.osengines.com/manuals/index.html

Download the OS manuals for their FS-26S-C (near the bottom) to get an idea of what you are looking at.

RE: 4-stroke engine
 

yeah, I know about Davis diesel.

I reeally want to stick a 4-stroke in it. and I plan on doing it to.

RE: 4-stroke engine
 

What is the project exactly?

RE: 4-stroke engine
 

Greg I have the asp 30, 52, 4 strks they are the same as magnum also under the SC Label in the UK . the ASPs are available from just engines but with the exchange rate of the GBP
to the the US$ -- now 2 bucks to the GBP costs a lot less to buy magnums stateside martin

RE: 4-stroke engine
 

the project, is area 51 classified. just kidding:D

I plan on taking my Jammin CRT truggy, and making new mounts, modding the clutch assem. and making a belt driven fan to keep it cool. so basicly its like taking a little 4cly car and stuffing a big block V8 or better yet a bigblock V10, now we're talken.:D hehe. and man is my CRT going to sound SWEET.

after I finish it there will be pictures in the RCU truggy forum. or I might post some here alwell.

RE: 4-stroke engine
 

OS also had a .40 fs designed to be used in cars

RE: 4-stroke engine
 

What kind of power does the supplied engine make? Using your analogy you might be going from a 600CC racing motorcycle engine to a Harley V-Twin. That might be lateral move in power, but a completely different animal. If you are going to use a large airplane engine be prepared to make many of your own parts, like clutch, engine mounts, exhaust, etc.

RE: 4-stroke engine
 

JB Comp:

If you do a little searching on Google, you should probably be able to find info on past four stroke conversions in cars. Just off the top of my head, from memory, there have been numerous T-Maxx trucks that have run OS four stroke engines. The OS26 four stroke was a factory mod to be used in Kyosho Super Ten cars and it used a cooling fan.

There is a fellow here on RCU who stuffed a Saito twin cylinder engine into his CEN monster truck. He also used a cooling fan.

The video you linked too, is an OS 120 supercharged four stroke. A monster sized engine stuffed into that truggy.

In Europe, it is wildly popular to put huge four stroke engines into sled pulling trucks. "Micropullers" they call them. (Well, two strokes also).

RE: 4-stroke engine
 

Heres a picture of a revo with a 4-stroke in it, I got the picture from RCtruckRacer

I'm running a STS 30 right now and that engine is a BEAST. but I want anew project to work on, and somthing, for when I crank it up at the track people go, what is that!:D

http://www.rcccs.com/index.php?act=A...pe=post&id=288

RE: 4-stroke engine
 

I'm planing on using a OS FS-70 surpass, or a OS FS-91 surpass, so need info on those two, how do I set the valves (or adj) how often do I replace the valves, cam, rockers, and on a 2-stroke engine the fuel/oil go through the crank, and case the lube the inside of the engine, so where dose the oil come from to lube a 4-stroke?

Can you rotate the carb on these engines?

I'm running a 13/62 gearing right now =4.76 gear ratio and I'm planing on running a 21/48 gearing which =2.28 dose that sound ok?

sorry for asking so many qusetions, I'm trying to get a hold of the guy with the revo, but I don't know how too.

RE: 4-stroke engine
 

Go to the link above and download the specific manuals. There is no need to replace any parts as long as you have the correct fuel. Model four stroke fuel is premix just like two stroke. OS recommends 18% oil in their four stokes. The engine shouldn't wear. After many, many, hours you might replace the ring and hone or replace the liner. You might consider making a straight manifold instead of using the airplane style.

As far as gearing you need to try to load the engine to full power (1.6HP for the FS-91) at 10-12kRPM. If the old engine topped out at 1.6HP at 25kRPM (searching turned that up) you probably need to change the ratio by a factor of 2 or so. So if the original is 4.76 you should try to get close to 2.38-2.0.

RE: 4-stroke engine
 

I know on my Dad's bike, he has to (or the manaul say) to check the valves often, and that they need to be shimed and all that stuff. so I didn't know if all thats needed on these fourstroke.

RE: 4-stroke engine
 

Yes, if you have a Ducatti the biggest maintenance issue is the valves. Every 3-4000 miles? You can check them as often as you like.

If you can wait I would use the OS FSa-81 when it arrives. It has a lubrication system that ensures oil will get to the top of the valve train and there are no breather vents to mess with. The FSa-56 is already out.

RE: 4-stroke engine
 

well I plan on getting a used engine, I can't afford a new one. with the rest of the stuff I have to buy.

RE: 4-stroke engine
 

dose anyone know of a good supercharger, not the ones made by RB?

RE: 4-stroke engine
 

No such thing. If you want a supercharged glow engine, go after a YS four stroke which uses the crankcase to supercharge the manifold.

http://www.yspower.co.jp/index.html