[cajunfj40]

Hello craysus,

CSRV vs. Poppet Valve - Coates International Ltd.

Using a cammed intake system similar to above, and taking changing the profile based on simple rotation. You could imagine taking this to the next phase, and implementing a Wankel style interface as the cam, instead of the twin cams used byu coates...and therefore simplifying the movement down even further..

Ooh, Coates! Nice rotary valve idea. Thought I'd seen some other arrangement of that before, here's a good article on the problems with rotary valves in general, and many attempts to get around them:
Rotary-Valve Internal Combustion Engines - way2speed I think the "Aspin" is the most similar to the one I saw.

Alternatively, electrically controlled "valves" could be utilised on a more conventional head...and if the valves opened / shut normally, but could be extended INTO the cylinder, to increase compression at the desired part of each scycle..(Making the valves a solid tube to take up volume..maybe twisting open / closed to vary between a solid tube and a fuel delivery / exit path)

There've been many attempts at solenoid-controlled valves. Some successful, most not so. I think the main problem was power consumption for direct electric solenoid control. Hmm, here's a Jalopnik article on a Koenigsegg Freevalve equipped Saab. What It's Like To Ride In A Car With The Camless Engine Of The Future Pneumatically actuated valves, so the electronics control the pneumatics, greatly reducing the power consumption of the solenoids, and pushing it off onto an air compressor instead. The article's low on tech, but hits the advantages pretty well. Freevalve has a website, too. FreeValve | Setting Engines Free I like the idea - I wonder how well it stacks up vs. cam phasers and other VVT designs from a cost/reliability standpoint.

Hello freebeard,

Quote:
Originally Posted by Permalink #34
What is to be gained over offsetting the wrist pin in the piston??
That mention didn't gain any traction, so I escalated to the Scuderi.

I poked around a bit and found the nice diagram in this article: https://rideapart.com/articles/free-...ders-explained It's for offset cylinders WRT the crank, but offsetting the wrist pin gets a similar effect.

Wrist pin offset on production engines is primarily about reducing piston slap, but can also be used to change the power output of an engine. This article Chevy Big-Block Performance: Displacement Decisions has some info about halfway down. Note the caveats in the article - the effect is small and it takes experimentation to get the right offset. Increased power from the same amount of fuel is an efficiency increase.

Hello DieselJan,

Hi Cajunfj40
I love Ecomodder and mean no harm. I know it is difficult to have threads that doesn't drift, just had a suggestion. Things like in the link above IMHO will bring the gains I'm hoping for. After that type of mechanical changes we can start improving with electronics, etc.

No worries, I didn't think you meant any harm. I'd have been sharper in my response if I did. As for mechanical vs. electronic, as much as I enjoy wrenching I can't justify sinking a lot of cash into an ICE anymore. Swapping in a junkyard-sourced modern turbo DOHC I-4 in place of my cam-in-block NA V6 is rather pricey. A custom or low-production prototype engine is likely to be even pricier. The cost seems comparable to a low-range EV conversion plus a small genset or pusher trailer for the few days a month I need to drive further and can't just borrow the family minivan or my MIL's truck.