Look at a chain saw or lawn mower or some two stroke gas engine. The air/fuel mixture is being fed into the crankcase. When the piston is going up on exhaust/compression it creats a low pressure area in the crankcase. This opens the reed valve and alows the air/fuel/and lubricating oil in. The oil is mixed with the gas. When the mixture fires and the piston starts down the pressure in the crankcase goes up and the reed valve closes, sealing the crankcase. As the piston continues down in the cylinder it passes holes in the cylinder wall that lets the exhaust gas out. Shortly after that more holes are passed that opens the transfer port that connects the cylinder to the crankcase. As the piston continues down it forces the mixture in the crankcase through the transfer port into the cylinder. When the piston passes BDC it starts up and the whole process starts again. If you have a blower as a GM 2 strok deisel you don't need nor have any use for reed valves.
Just after WW2 the British designed and almost built an airliner that would have used 4 large radial engines as gas genorators using the exhaust to drive turbines driving the props. Logic jumped in and they put a compressor and burner cans foward of the turbine and built a turbo jet. The Curtis-Wright 3350 cubic inch radials in use on DC7 aircraft when I started being an A&P had turbines mounted around the collector ring and driven by exhaust gas. They were geared into the crankshaft and helped drive the prop. Called them "Turbo-Compound"
I understand the principle - but even so - the blown GM diesel two stroke doesn´t have reed valves because it has normal valves, or....? Not really a pure two stroke. Still difficult to see how you could do this without using the crankcase or a blower. My motorbike gets by just fine without any kind of valve gear or an expansion exhaust.
Uhhh.. maybe as applied to weed wackers. But you obviously haven't looked at real 2-strokes in quite some time. The unburnt fuel thing went out in the 80's. Modern racing 2 strokes, think 250cc GP motorcycles for one, are very efficient and produce a whole lot of of power for their displacement. There has been direct injection versions that have proven they can be as clean as 4 strokes. But alas the powers that be, think government, had already labled them as bad. The direct injection also gets rid of some of the nasty oil issues as well. But still 2 stroke oils have come a long way as well and burn much cleaner than ever before. enough for now, got to give a customer bad news...
To see that theory put into practice, look at snowmobiles, where weight is very important for race sleds and mountain sleds. They can't make a 4-stroke with the hp to weight ratio that compares to 2-strokes, so they're using direct injection to help the emissions issue. I run a 150hp 2-stroke twin in my mountain sled, one guy can easily pick up the engine like it's a toy. It's good for well over 200hp with mods.
When I was a young pup I worked as a Millwright and we worked and overhauled very large 2 stroke compressor engines. These all had fuel injection valves on the heads, and exhaust ports in the cylenders. Really cool power plants. Clark and Cooper Bessemer were the main stay. These had seperate power cylinders on a common crankcase. Big as a house, maxed out at about 300 rpm and 1000 to 1500 hp. They all had Babbit or alumuum bearings with a cam shaft to open the fuel injection valves. The engins would run for years with a little port cleaning bearing checking and carbon removal. They had to be set up very leval and then grouted in with Cement or Epoxy grout. Not many around any more, Smog and polution took their tole. But they were a true two cycle, sounded real cool when started up.--TV
Didn't Mercury make a big nasty V-8 two stroke outboard????? I've been in some pretty fast bass boats with knarly vee two strokes. Wouldn't it be easier to convert one of those to an automotive application rather than try to make a small block Chevy engine a two-stroke? I saw a two stroke outboard motor powered midget racer some years ago, the car was almost impossible to drive, it had explosive power that was really difficult for the driver to get it down to the track.......but it sounded really bad-ass.
That sounds real cool.....wish I could see one. Back on subject, this kind of question brings up good discussions, even if it's a strange idea. Out of the box thinking leads to real cool ideas sometimes....
What a thread! WoW Assholes and elbows. Turning a four stroke as in a Chevy into a two stroke can be done but it wouldn't be worth the effort. About 45 years ago a friend in Ireland took a BSA 500cc single four stroke and turned it into a two stroke. A two stroke uses crankcase compression to move the air/fuel mixture into the cylinder. Plus an amount of oil to lube the bearings. He cut intake ports into the cylinder wall and ran runners to the crankcase. Both intake and exhaust were used for exhaust. An intake port was cut in the crancase for the carb. In the end he said it wasn't worth the effort. A Chevy V8 (or any other V8 for that matter) couldn't be turned into a conventional two stroke because of the basic two stroke principal of crancase compression. Each cylinder would have to be sealed from each other. I suppose it might be possible to tackle the problem some other way but to turn a Chevy V8 into a conventional two stroke. No it isn't possible.
Bruce Crower did this, on a Brit Bike... I remember reading about it ( probably in HRM ), long time ago.
You dont need to run the intake charge through the Crank Case, if you use a low boost Blower. The tricky bit would be to cut the Ports in the sides of the Cylinders, when you have to go though a Water Jacket as well...
My intentions with this thread was just to see if an old crazy idea would be theoretically possible, not to collect suggestions on alternative twostroke engines. Going to build a high compression, shortstroked, highcammed, highrevving smbl chev. for my next coupe, will try my best to make it sound like the crazy twostroke in my dreams!! Interesting thou that some of you guys more or less says it possible, while some says it is not!
I´m actually wondering if a Flatty wouldn´t be easier to convert, since the inlet ports already run alongside the cylinders. If you blank where the valve comes through and cut the port through into the side of the cylinder, then its a start. Or use an aluminium block chevy and run the inlets through the block.That way you could experiment with port timing with different liners. In an iron block its probably all a bit more final once you start cutting.
Welcome to the HAMB... It can get pretty strange around here sometimes, but for the most part, just a bunch of good 'ole boys [and a few gal's] who like to talk cars and swap lies. With enough money and time, ANYTHING is possible... But that still dont make it a good idea. Want a v8 that sounds like a 2 stroke? Simple... Get a v16
Thanks for the welcome!! Yeah i think this is a really greate place with a lot of nice people with a enourmous amount of knowledge!! Louisville Ky.... Yes!! had some good memories from there.... 25 years ago...
Just to keep this discussion going, I'm going to share with you guys the reason I'm no longer an engineer for GM. It's all because of this engine. The Bourke VLB-400 I wont go into the exact reasons as to why I'm no longer with GM, but trust me, it got ugly! So ugly infact, that you will probably never see or hear about this engine again in your life except to hear it from me.
The original question here was could a chevy V8 be turned into a two stroke. I suppose it could with enough money and effort but not in the manner originally described. The basics of two strokes and four strokes are completely different. Somewhere aong the line I remember Husqvarna or Husaberg making a two stroke that had a recirculating oil system as per four stroke. Some how, like the Burke, they sealed the crankcase. Can't remember any details unfortunately. To make a V8 two stroke in the classic manner would be extremely easy. Gran Prix motorcycles were using four cylinder two stroke for a long time until they were banned in favor of four strokes. To double up to 8 cylinders would not be that difficult. Such a motor may have existed but for the rules restricting them to four cylinders. But to turn the Chevy into a two stroke as originally described? No.
Could this be the sort of thing you were looking for...? http://www.break.com/usercontent/2007/12/2-Stroke-v8-sand-car-415394.html Search for Evinrude V8 - there seems to be plenty of info.
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