Advanced Engineering Tech - Unusual OHC Chevy?
08-18-2010, 10:47 PM
I was having a head discussion with my buddy and he was talking about making some kind of ohc setup without tradition type valves but more of a rotating setup, I told him I had seen this done a while back and it was a small block chevy with a rotating sphere with a hole cut in it, I looked on google for a few hours but couldnt find anything, does anybody remember this or have a link for it?
08-19-2010, 09:10 AM
A quick google search for rotary valve engine comes up with this.
but its been disproven over and over. The animations are nice for a good laugh.
08-19-2010, 10:05 AM
wtf? that is very unusual. and probably horribly inefficient.
08-19-2010, 10:17 AM
There are so many different designs of engines, valvetrain, etc that you will know soon enough what is a good and feasible idea. Their names will be known lol.
Some are just purely a money pit.
08-22-2010, 12:52 PM
Aardema development. does a SOHC for the SBC and Pete has done some other cool things.
08-23-2010, 07:22 AM
i think Neslon racing engines is coming out with a 32valve SBC based engine. Should be pretty intresting watching it spin to 8K!!! :)
09-17-2010, 07:41 PM
I actually read all about Coats and his rotary valve engines. They were EXTREMELY efficient. He did a test on a Ford 302 motor that dynoed at 250 hp having been converted with his heads using the same carb and intake made over 450hp and was even more fuel efficient too! Having the rotary valves eliminates the need for high pressure valve springs to keep from valve float on higher lift cams at higher engine speeds. The main friction in an engine is from the valve springs. He had test engines running at over 14,000 rpm still making power! The only thing holding them back was the rotating assembly.
I got this information from Engine Masters Magazine back in 2000-2002 (cant remember exactly). Since then I have looked him up and I believe somebody bought him out (oil companies?) and he now uses his technology in highly efficient generator motors in Canada.
09-17-2010, 10:36 PM
I file this one under the skeptical-borderline-impractical.
09-18-2010, 01:30 AM
the coates engine; i imagine a system like that would not handle much wear before it started leaking. but until then...:eek2:
really though, there is no poppet valve in the middle of the air stream, no valve harmonics, only unimpeded airflow. rpm is only limited by material strength and EFI capabilities. i wish they made commercially available heads for my LT1 i'd go kill some vettes
09-18-2010, 09:43 AM
You'd have harmonics. Since they are rotating on pulses and that they have to withstand cylinder pressure that would exert a force upward on a specific rotating globe thingy ultimately leading to an entire flexing situation.
Material properties would be another issue. How to keep super close tolerances of aluminum head with steel rotating globe thingy in the face of high pressure, contaminants, and fluctuating temperatures.
I could see it working for a specific industrial engine scenarios though.
09-18-2010, 10:19 AM
Thats why it took him 15 years to develop. He had problems with sealing, but now he uses a carbon ceramic seal around the chambers. Who knows? It could work, and be reliable! I would love to see this become available to the public. Even if it doesnt have longevity, it could still be used for some crazy power in a drag car. They rebuild them after every race anyways!