Two stroke type IV?, Random thought of the day |
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Two stroke type IV?, Random thought of the day |
bondo |
Aug 10 2004, 12:50 PM
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#1
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
Has anyone ever attempted this sort of conversion? I would think it would require VERY extreme mods to the case and cylinders.. but you could get soooo much power! (and a hole in the ozone layer that follows you around)
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phantom914 |
Aug 10 2004, 12:58 PM
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#2
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non-914-owner non-club member Group: Benefactors Posts: 1,013 Joined: 24-February 04 From: Covina,CA(North ofWest Covina) Member No.: 1,708 |
QUOTE(bondo @ Aug 10 2004, 10:50 AM) (and a hole in the ozone layer that follows you around) You want to run it on CFC's?(IMG:style_emoticons/default/huh.gif) (IMG:style_emoticons/default/biggrin.gif) |
J P Stein |
Aug 10 2004, 01:06 PM
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#3
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Irrelevant old fart Group: Members Posts: 8,797 Joined: 30-December 02 From: Vancouver, WA Member No.: 45 Region Association: None |
QUOTE(bondo @ Aug 10 2004, 10:50 AM) Has anyone ever attempted this sort of conversion? I would think it would require VERY extreme mods to the case and cylinders.. but you could get soooo much power! (and a hole in the ozone layer that follows you around) Are you any relation to Mueller? (IMG:style_emoticons/default/laugh.gif) |
phantom914 |
Aug 10 2004, 01:08 PM
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#4
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non-914-owner non-club member Group: Benefactors Posts: 1,013 Joined: 24-February 04 From: Covina,CA(North ofWest Covina) Member No.: 1,708 |
What about mods to the case and using heads and cylinders from four air-cooled open class dirt bike engines. My 490cc made about 50 HP and 4x ft-lbs. Multiply that by 4 and that would be one hot engine.
Andrew |
crash914 |
Aug 10 2004, 01:28 PM
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#5
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its a mystery to me Group: Members Posts: 1,826 Joined: 17-March 03 From: Marriottsville, MD Member No.: 434 Region Association: MidAtlantic Region |
Hmmmm...I did have the thought of installing a motor from an outboard...only problem was the drag from dragging a lake arould with you....
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phantom914 |
Aug 10 2004, 01:30 PM
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#6
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non-914-owner non-club member Group: Benefactors Posts: 1,013 Joined: 24-February 04 From: Covina,CA(North ofWest Covina) Member No.: 1,708 |
QUOTE(crash914 @ Aug 10 2004, 11:28 AM) ...only problem was the drag from dragging a lake arould with you.... ..and the rust (IMG:style_emoticons/default/ohmy.gif) Andrew |
Jake Raby |
Aug 10 2004, 01:53 PM
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#7
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
It has been done, more than once. The cylinders were very wild!
With enough time/ money anything is possible! |
bondo |
Aug 10 2004, 02:36 PM
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#8
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
Jake: hehe, I figured if anyone knew it'd be you (IMG:style_emoticons/default/smile.gif) Do you know what the power output/longevity was?
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914werke |
Aug 10 2004, 02:44 PM
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#9
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"I got blisters on me fingers" Group: Members Posts: 10,057 Joined: 22-March 03 From: USofA Member No.: 453 Region Association: Pacific Northwest |
Why re-engineer just find the 3 cyl. from a Saab Sonnet (IMG:style_emoticons/default/barf.gif)
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lapuwali |
Aug 10 2004, 03:02 PM
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#10
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 |
One doesn't necessarily need to redo the cylinders, though it would still be a major job. You could run the cam at crank speed and use a custom fuel injection system. The only time I've seen this done (two-stroke with cams and poppet valves), a supercharger was used as well, to help scavenge the cylinder fast enough on the exhaust stroke. I think it also used direct injection and the blower only pushed air.
Given the valvetrain speeds required, I'd expect you'd either be limited to about 3500rpm, or you'd need OHC heads. At 6000rpm, the valvetrain would "see" the same speeds/loads as it would at 12,000rpm on a four-stroke. I doubt the pushrod valvetrain would hold up to that for long, if at all. There's been quite of bit of work on making clean two-strokes. An Australian company called Orbital managed to draw a lot of press about 10 years ago, and got GM and Ford interested for awhile. They used direct injection and managed to get a 1.0L three-cylinder to make as much power and torque as a Ford 1.9L four, at less than half the weight, and 2/3rds the size. Emissions w/o a catalyst were equal to the emissions of the 1.9 with a catalyst. Quite impressive. No idea why the idea wasn't pursued. I'd expect longevity concerns were part of it, as well as the politics involved in anything "new". |
bondo |
Aug 10 2004, 03:58 PM
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#11
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
Wow, I didn't know 2 stroke technology had gotten that advanced. I suppose these clean 2 strokes have a regular pressure fed oil system instead of the oil in gas setup? Seems that the valvetrain speed issue could be resolved by using 4 valves per cylinder and alternating, so only one valve would be open at a time, reducing valvetrain speed. I could see how a valved 2 stroke would need a turbo or supercharger, if it didn't have the advantage of a pressurized crankcase induction. I should do some experiments with a lawnmower engine.. I could clean up on the Jr. Dragster circuit (IMG:style_emoticons/default/smile.gif)
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phantom914 |
Aug 10 2004, 04:22 PM
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#12
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non-914-owner non-club member Group: Benefactors Posts: 1,013 Joined: 24-February 04 From: Covina,CA(North ofWest Covina) Member No.: 1,708 |
QUOTE(bondo @ Aug 10 2004, 01:58 PM) Wow, I didn't know 2 stroke technology had gotten that advanced. I suppose these clean 2 strokes have a regular pressure fed oil system instead of the oil in gas setup? Yes, one of the reasons it burned cleaner is that the atomized fuel never entered the crankcase and so never mixed (got contaminated) with the oil. The fuel was injected directly into the combustion chamber with high pressure air (IIRC) to super atomize the fuel. Andrew |
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