Revtec, a very peculiar looking engine

[sergei]

http://www.revetec.com/

The Directors are pleased to announce that the X4v2 petrol engine achieved a repeatable Brake Specific Fuel Consumption (BSFC) figure of 212g/(kW-h) or (38.6% engine efficiency) with a best figure of 207g/(kW-h) or (39.5%) at our requested target test of 2,000rpm with a BMEP load of 450kpa (approximately 75% load) and an air/fuel ratio of 15.2:1 using 98 RON petrol and a 10:1 compression ratio. We also achieved a BSFC figure under the same rev and load conditions using an air/fuel ratio of 14.5:1 of 238g/(kW-h) or (34.4%)...

The biggest "flaw" I can see with this engine is that roller bearing take full torque of the compression stroke.
Can they take that sort of load/jerk?

Very interesting concept, can be used (and I think it is used hence high efficiency claim) to change the piston speed depending what part of the combustion the stroke is...

[xsspeed]

Was about to say it looks a bit like the old propellor aviation motors, then saw on their site thats what the initial design was for.

I see your point re: the bearings, I assume they would be rod bearings?

[bbq1988]

Ohh shineys... reminds me of a boxer crossed with a rotary

[sergei]

Was about to say it looks a bit like the old propellor aviation motors, then saw on their site thats what the initial design was for.

I see your point re: the bearings, I assume they would be rod bearings?

Yeah, "rod" bearing, well plate in this case....

[xsspeed]

I think roller bearing is what I meant (as opposed to ball bearing)

What do the twin camshafts at the top of the engine operate?

[sergei]

It looks like they operate dynamo...

[xsspeed]

I wonder how reliable the engine is, a lot of rotating parts!

[Lloyd]

Old

http://www.enginehistory.org/Packard/jp ... geared.jpg

http://www.enginehistory.org/Packard/jp ... harged.jpg




And more pretty pictures if you like those: http://www.enginehistory.org/packard1.htm

[touge rolla]

a disturbing lack of valves, I thought mankind was past this pushrod nonsense

[method]

pushrods are the future!

Would have too many belts if it trued using overhead cams

[KinLoud]

looks like the old orbital engine that high claims were made about...

[Mr Revhead]

ah that sarich thing....... i wonder what happened to him?

[Adamal]

pushrods are the future!

Would have too many belts if it trued using overhead cams

Nahh mate, you'd just use a Subaru one!

Interesting concept... I'd like to see one in action.

[method]

Subarus have too many belts as is, this would have twice the ammount of belts as a subaru.

dont see the problem with pushrods like that, it still uses a cam to move it. Just has a few extra components that may break...

[Mr Revhead]

that engine is more a proof of concept rather than a full production version
so pushrods cheap and easy to make/setup for what is probably an underfunded team.

if $$ was no object, then they would use an magnetic/pneumatic system or similar and have no belts or cams etc

[method]

Segri, thoughts on a hybred electric system with a efficent gas turbine that charges the battery rather than a standard petrol engine?

Just a random thought.

[rollaholic]

Subarus have too many belts as is, this would have twice the ammount of belts as a subaru.

dont see the problem with pushrods like that, it still uses a cam to move it. Just has a few extra components that may break...

seems like an odd thing to say - subbies have one cambelt just like most other belt driven engines

as for pushrods... not really the best, extra sets of tolerances = less precise valve actuation, which means less efficient!

[Jdawg]

They are looking at the aviation market so engine will only be revving to 2000-2500 rpm. Pushrod tech is cheap and reliableto design, build and maintain, esp in a motor with low revs.

[method]

Subarus have too many belts as is, this would have twice the ammount of belts as a subaru.

dont see the problem with pushrods like that, it still uses a cam to move it. Just has a few extra components that may break...

seems like an odd thing to say - subbies have one cambelt just like most other belt driven engines

as for pushrods... not really the best, extra sets of tolerances = less precise valve actuation, which means less efficient!

Your right, by too many i ment too long

But not longer than any V8 i supose..

[sergei]

Segri, thoughts on a hybred electric system with a efficent gas turbine that charges the battery rather than a standard petrol engine?

Just a random thought.

I had that idea a while ago, small APU unit of jet plane and nice AC motor...