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Discussion Starter · #1 ·
Has anyone here thought if it is possible to make a free valve system that uses pneumatic and electric solenoids? It in my early understanding of it is possible and may help with issues concerning the head issues we all know of but disregard because we are gluten for punishment.. please let me know if any of you are developing one or have thought the same idea.
 

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I've not seen valve issues talked about. Cylinder cooling is a complex issue that is less the head and more of a mixture of unequal exhaust scavenging and lack of piston squirters on the EJ. It hasn't been an issue really on the fa platforms.

Typically it's ringlands, rods, and on the high power end cylinder and head deflection. A solenoid valve system wouldn't help more than heavier valve springs.

You may have power potential and the ability to custom tune the power and dynamically for all occasions, but that's a complex solution. I'm sure you could figure something out, but tuning would require aftermarket engine management. Maybe haltec?
 

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I had an issue where my timing belt skipped and caused my valve to smash into pistons. I was thinking it could be programed into a micro computer like a raspberry pie an if this then that script where if the sensor looses signal or sees something wrong then it will send a signal to the solenoids to put the valves in a position where they will not be hit by a piston. And you would have to go standalone ecu as well as hav a compressor in the trunk to run the pneumatic solenoids and a very good battery. But I was wondering if it would be a new idea to solve an issue as well as a challenge to possibly do a concept on. It's been done on a miata before and the cool thing about solenoids is that you don't need to run liquid cooling to them so that would make it a bit less complicated to set up, as well as you would be able to access the spark plugs easier for maintenance
 

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in the old school V8 days they went from timing chain to gear drive timing to get around the problem of failures at high rpm and/or high pressure valve springs doing a number on the timing chain/gears.
you could design a gear drive system to replace the timing belt and pullies but it would probably have 14 gears lol
pneumatic controlled valve train sounds like formula 1 technology and if it was viable the rally race guys might be using it. it could be cost prohibitive or not allowed by rules. cheaper for the racers to just change timing belt after a few race days.
in F1 they run 12,000 rpm so they may have done it to counter harmonics problems. it could provide some kind of damping effect because spring forces get "stacked" at certain rpm's due to harmonics lining up.
i didnt google any of this recently. i looked into this stuff maybe 10 years ago i knew a guy with a BB chevy dragster (had timing gear drive instead of timing chain and gears) he kept having valve spring failures. even brand new high dollar top of the line springs, the best he could buy, would fail because of the high rpm and high spring seat pressures.
 

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I had an issue where my timing belt skipped and caused my valve to smash into pistons. I was thinking it could be programed into a micro computer like a raspberry pie an if this then that script where if the sensor looses signal or sees something wrong then it will send a signal to the solenoids to put the valves in a position where they will not be hit by a piston. And you would have to go standalone ecu as well as hav a compressor in the trunk to run the pneumatic solenoids and a very good battery. But I was wondering if it would be a new idea to solve an issue as well as a challenge to possibly do a concept on. It's been done on a miata before and the cool thing about solenoids is that you don't need to run liquid cooling to them so that would make it a bit less complicated to set up, as well as you would be able to access the spark plugs easier for maintenance
That's massively uncommon.

I don't think a raspberry pi would be what you want. Even with the high speed canbus systems I don't think the data loop would be fast enough for the raspberry pi to work.

Pneumatics is flat out. Air would be too compressible. You'd want something like hydraulic or electric. There is a company that has developed the electric yet although I don't know if it was ever implemented. FIAT was working on it too for the dart years back but I don't think it went anywhere.

Your challenge is tracking the exact position of the crank shaft at every moment.
 

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I had an issue where my timing belt skipped and caused my valve to smash into pistons. I was thinking it could be programed into a micro computer like a raspberry pie an if this then that script where if the sensor looses signal or sees something wrong then it will send a signal to the solenoids to put the valves in a position where they will not be hit by a piston. And you would have to go standalone ecu as well as hav a compressor in the trunk to run the pneumatic solenoids and a very good battery. But I was wondering if it would be a new idea to solve an issue as well as a challenge to possibly do a concept on. It's been done on a miata before and the cool thing about solenoids is that you don't need to run liquid cooling to them so that would make it a bit less complicated to set up, as well as you would be able to access the spark plugs easier for maintenance
It hasn't really been done on a miata. One guy managed to make a lawnmower engine idle with pneumatic solenoids and then made the parts for an NA 1.8 head. I don't know if it went anywhere but there were no power gains worth reporting.

For reliability, solenoid or electronics failure is more likely than skipped timing. Also most hydraulic and pneumatic solenoids start to leak by internally and need replacement approx every 5yrs even in slow and intermittent industrial applications. For engine valves, most off-the-shelf solenoids would dissolve in a few months. You would need to find much more durable ones like the ones in injectors. You also need stronger valve seats and valves. Solenoids will slam the valves back in their seats instead of guiding it back smoothly like a camshaft.

Replacing the cambelt more frequently or converting to gears as suggested will be a much more reliable system.
 

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Discussion Starter · #10 ·
in the old school V8 days they went from timing chain to gear drive timing to get around the problem of failures at high rpm and/or high pressure valve springs doing a number on the timing chain/gears.
you could design a gear drive system to replace the timing belt and pullies but it would probably have 14 gears lol
pneumatic controlled valve train sounds like formula 1 technology and if it was viable the rally race guys might be using it. it could be cost prohibitive or not allowed by rules. cheaper for the racers to just change timing belt after a few race days.
in F1 they run 12,000 rpm so they may have done it to counter harmonics problems. it could provide some kind of damping effect because spring forces get "stacked" at certain rpm's due to harmonics lining up.
i didnt google any of this recently. i looked into this stuff maybe 10 years ago i knew a guy with a BB chevy dragster (had timing gear drive instead of timing chain and gears) he kept having valve spring failures. even brand new high dollar top of the line springs, the best he could buy, would fail because of the high rpm and high spring seat pressures.
I've not seen valve issues talked about. Cylinder cooling is a complex issue that is less the head and more of a mixture of unequal exhaust scavenging and lack of piston squirters on the EJ. It hasn't been an issue really on the fa platforms.

Typically it's ringlands, rods, and on the high power end cylinder and head deflection. A solenoid valve system wouldn't help more than heavier valve springs.

You may have power potential and the ability to custom tune the power and dynamically for all occasions, but that's a complex solution. I'm sure you could figure something out, but tuning would require aftermarket engine management. Maybe haltec?
in the old school V8 days they went from timing chain to gear drive timing to get around the problem of failures at high rpm and/or high pressure valve springs doing a number on the timing chain/gears.
you could design a gear drive system to replace the timing belt and pullies but it would probably have 14 gears lol
pneumatic controlled valve train sounds like formula 1 technology and if it was viable the rally race guys might be using it. it could be cost prohibitive or not allowed by rules. cheaper for the racers to just change timing belt after a few race days.
in F1 they run 12,000 rpm so they may have done it to counter harmonics problems. it could provide some kind of damping effect because spring forces get "stacked" at certain rpm's due to harmonics lining up.
i didnt google any of this recently. i looked into this stuff maybe 10 years ago i knew a guy with a BB chevy dragster (had timing gear drive instead of timing chain and gears) he kept having valve spring failures. even brand new high dollar top of the line springs, the best he could buy, would fail because of the high rpm and high spring seat pressures.
Koenigsegg has implemented it into their motors and there are a couple people making home brew versions for their cars. (Mostly miatas and other extremely modifiable veichles) but I was thinking it could be a possibly. It definitely would require alot of trial and error which is out of my budget for the time being. Looks like I'm just going to be stuck replacing timing belts sadly. Maybe one day someone will develop it.
 

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Koenigsegg has implemented it into their motors and there are a couple people making home brew versions for their cars. (Mostly miatas and other extremely modifiable veichles) but I was thinking it could be a possibly. It definitely would require alot of trial and error which is out of my budget for the time being. Looks like I'm just going to be stuck replacing timing belts sadly. Maybe one day someone will develop it.
Future tense, they will implement it in the gemera's 3 cyl engine.

There's a difference between making a working experiment and making it better than the OEM timing system. The 2nd part is a 7 or 8 figure project and no one's going to spend that on retrofitting it to an out of production engine.

And consider this, a timing belt is a few hundred in parts, lasts 10years and it's never affected by software bugs or failed sensors. A solenoid will cost 200-300 per solenoid times 16, will last 5 years and any software bug or failed cam/crank sensor could make it slam the valves into pistons grenading your engine.
 
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