Glow plug v4

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choptop

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Got a quick question and hope for some help.... I am building some rc replica cars and when it comes to engines it gets complicated.... I work with Conley Precision Engines and do some machine work on engines and i build his chassis for him. I am looking at $20,000.00 cars with his engines but i would like to try something different and i would like to use standard parts of a glow plug style OS engine and make it like a v8 or a v4 engine to put into some of my model cars...Has anyone every did this and if so is there pictures or prints to look at? Any help would be great and i would like to discuss with people on why or why not....Thanks
 
Well . . . . I don't think you will see too many of them. The parts are big money. Most people here would just rather make the parts because it's cheaper and adds to the enjoyment of the build. Think of it like this, building an engine with purchased parts is like going golfing and only playing 11 holes. Personally I would play 18 even tho it takes longer.

If you did make an engine using OS parts you would end up with something that would look more suited for an airplane. An automotive engine has a specific style that you probably can't achieve with RC parts.

Another thing to consider is cooling. The mini V8's you see here and on Youtube create a lot of heat. Runs of more than about 3-5 minutes are tough on them You radiator would need to be huge. A boat would be a much better choice with the almost unlimited supply of cool water.

All that aside there is no doubt that it could be done with with some thoughtful planning and a few sharp tools.
 
Here are plans for v12 & v6 RC-like 4-stroke glow configuration for reference or ideas. No commercial RC parts cross compatibility that I'm aware of (other than maybe carbs, possibly rings?). But like Steve points out regarding cooling, both are of the aircraft engine variety & have the big diameter whirly fan up front.

http://www.engineman.de/

http://www.cad-modelltechnik-jung.de/baumotor/6_zy_v.htm
 
I have considered it. The only thing it saves you from making is sleeves, pistons, and rings, and maybe valves and springs, if you can design a head to work with them, they are short. It will still lack an oil ring. Purchased sleeves might not work if the head is one piece or may need to be ground to equal heights. Rocker arms maybe. I was going to go even cheaper and buy Magnum parts. I have another project going where I might use an Enya 4C crank, rod, piston, and rings and build the rest.

I just caught up on Conley's updates the other day. Even though I've seen his work for years, it still amazes me. I'd love to visit his shop.

I disagree that it's cheaper to make the parts, especially if any heat treating or plating is involved. I modify a lot of RC four strokes and haven't built a whole engine yet. It's all about what you want to do. I have little interest in building an engine that runs no load, but I love watching them at NAMES.

Greg
 
Thanks for the response this is what im looking for... I was wanting to make a crank for all of the pistons hook to so that was a given to do but the piston,rods and sleeves that can be purchased and save alot of time and money doing a build like this. I will make casted aluminum blocks and heads for these (lost wax casting) and use purchased parts for the other items (except crank)...I have a cnc machine shop and do alot with casting, i learned from Gary Conley... My concern is the firing of the pistons and getting the glow plugs to work all at the same time? Im a little fuzzy on that part but machining and designing is what i can do...

Thanks again and please lets keep on this topic..
 
I just did a Google under '4 stroke rc car engine' & it does turn up some interesting creations for reference. I cant post links right now, but including some screen grabs. They seem to be confined to single cyl commercial retrofits (maybe out of cost but probably because there are few/any RC commercial V's & even only a handful of opposed variations).

How they are cooling these 4S engines in car enviornment would have to be further investigated. I would think heat that would be an issue in enclosed enviornment. What little I know of nitro rc heli's, I think they mostly incorporate fans & 99.9% single cyl?

rc car 1.jpg


rc car 2.jpg


rc car 3.jpg
 
The plugs are all just wired in parallel. There are a couple sources for glow plug drivers up to 9 cylinders, but they aren't cheap. Glow ignition is just about getting the compression ratio right 7-8:1 is typical, higher if you pay attention to the combustion chamber. Glow eliminates the distributor and drive.

Rods are of no use to you unless you get into the larger engines which have split big ends. In those sizes parts do get expensive, but depending on how many you're making it could still be cheaper. If your intention is to sell these, cost becomes much more important. The OS FT-160 rod is $51, piston $35, liner $37, rings (not OS) ~$12, valve/spring set $58. A V8 then becomes $1544, for just these parts. If you're making one or a couple, probably acceptable if the selling price can absorb it. If you're making dozens to sell, you should be making these parts. Using these parts would get you a 6.4ci (105cc) V8.

The easiest thing to do is buy the parts you might use and measure them to see if you can make them work in your design. A used FT-160 can be had for around $400 on Ebay at times.

Peter, most of the time those cars have a fan of some sort installed if the engine is not out in the open. Glow engine get some cooling from the fuel so they don't need quite as much air as a gas engine.

4-stroke_truck006.jpg
 
I disagree that it's cheaper to make the parts, especially if any heat treating or plating is involved.



With the prices you have cited in the above post how can you not think it's cheaper to make them.

$51 for a rod. $20 in material and I can make 10
$35 for a piston and again a $30 rod of 7075 and i can make 10
$37 for a liner and another 10 for a 20 dollar piece of stock.

Unless you are factoring in shop time which to a hobbiest doesn't apply, What am I missing?
 
Those prices only apply if you buy OS parts with huge mark up.

ASP engine parts can usually be had for around $4 a piston, $4 per ring and about $5 for a cylinder sleeve. Thats around $100 for a v8.

Unfortunately though, things like rods and valves are a lot harder to find and a lot more expensive, so they may be cheaper to make.
 
ASP engines? Thank you, been looking for information about this.


Sent from my iPad using Model Engines
 
For an As Soon as Possible engine have a look here !

http://fabrication-moteur.over-blog...et_Proton_dream_projet_2013_2014-7082670.html

this young buddy is working hard at a similar attempt for building single & multi 4 stroke engines with "ready made" parts.
the main points (apart the beautiful castings he made) are cylinder liners cut from a polished seamless steel tube, pistons from a commercial anodized aluminium bar stock and rings with viton orings; machining is reduced to holes for wrist pins and grooves for orings, amazing.
I'm now building a 4s single with one of his cored monoblock castings, to test by myself his approach, and I will post the results soon.
 

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