renagade_rotary

Im working on a car to gain experimental experience in the rotary world

I really want to build a 2 rotor motor that exceeds 10k rpms safely(as safe as possible)

My goal is to hit anywhere between 11k-15k tell me if thats reasonable or not

anyways which is better

12a N/A (i have already)
12a turbo

13b N/A
13b turbo (current engine in car)

if anyone has done this pleas contact me personally and share your knowledge!

BDC

Not reasonable.

B

DarkKnightFC

I believe something that would rev that high would have a problem staying running in anything less than full throttle, clearances maybe? That and the fact that you're only going to make power up to a certain rpm, the rest would just be for ***** I guess. Just guessing, and it would take a shitload of money....

renagade_rotary

If sequential turbos were put into play one that kicked in at about 4.5k and carried up until a bigger turbo could step in

if you think about it in order for formula ccars to havve power in those rpms they integrate a variable valve timing or something along the lines of vtec

im jsut brainstorming here

PDF

11,000 is realistic but 15,000 is not. A large bridgeport or PP 12A will reach 11,000+ easily and reliably in short bursts (e.g drag racing) but sustained 11k rpm may be a different story. I would use the factory crank, a pair of lightened and clearanced 6 port rotors, and machined down 20B or REW stationary gears.

Black91n/a

Why? Unless you're racing and are forced to use an NA engine by the rules it makes a lot more sense to build a turbo 13B and up the boost to get power rather than spinning it to stratospheric speeds. Most likely you'll not be making any more power way up high unless you've got massive ports and if you do it'll not idle below maybe 2k rpm and will be undrivable on the street and will have a lifespan measured in minutes.

If you really want to rev it really high you'll need to race clearance the rotors to prevent the corners from hitting the side plates at high rpms due to eccentric shaft flex. You could also get a 2 piece e-shaft with the center bearing which should more or less eliminate that problem.

renagade_rotary

mainly because i want to hear it and the self pride that would come with the accomplishment

Kenku

Practicality of the whole thing aside... ah ha ha ha... no. VTEC's just emissions ****.

Black91n/a

Yes and no. There's more than one version of VTEK, some are more for economy, whereas the ones they put in the Si's, the Type R's and so on are for performance. They first came about from racing, then first appeared on the road in the Acura NSX, a supercar, so yes, it's for performance.

While I think it'd be cool to have a really high spinning engine, it'll cost a ton, be crappy to drive and die really quickly. Not exactly practical.

89t295k

Do me a favor if you try this.
buy a steel scatter sheild. The flywheel can kill you,cut a fuel line and burn you to the ground.
GL

renagade_rotary

If I do this i will encase the rotating assembly in a shatter blanket and plate armor in the tranny tunnel...I never do a single project without thinking of the safety precautions


I've always been that way to the point of overdoing safety in some peoples opinions

Kenku

They did not, in fact, come about through racing. VTEC broadens the powerband in areas that are largely useless in roadracing, and adds a lot of mass to the valvetrain which does nothing good for high-RPM longevity. It's a way of having a performance-oriented cam that grannies and emissions people can live with. It's perfectly possible to make the same kind of power at the same kind of RPMs on the same displacement engines without any sort of variable valve timing.

F1 engines, even those built by Honda, use finger followers with pneumatic valve return systems. Before that, they used finger (always been a Honda thing) or bucket followers with valvesprings. Recently, some teams *were* using variable length intakes to broaden the torque curves, ala the 787B... but those got banned.

So to sum up, no, it's for emissions.

Black91n/a

Sure you could make the same peak power, but with no variable timing it'd give you much worse low rpm power, a bad idle and bad emissions, making it impossible to offer an engine of that performance for sale in a road car, as few people would be willing to put up with that and it wouldn't be legal for sale due to the emissions. I was pretty sure I'd read that it came about through racing, but I could be wrong, but It certainly came about through a desire to give more performance. Systems can do more than one thing at a time, so it can be for emissions and power at the same time.

Ok that's way off topic. Lets try to get this back in line with the subject of the thread.

Some things to consider: Basically, a peripheral port will be needed to be able to breathe that high, a lightweight rotating assembly from Racing Beat will help reduce stresses, a 2 piece e-shaft from Guru to reduce flexing, probably clearance the rotor tips anyway, carbon apex seals to reduce the chances of them chattering on the housings and flying apart from the speed (probably still will if you try for 15k), ballistic shields, a 5.5" racing clutch/flywheel will be better able to handle the speed, as they're used in formula racing engines (well the clutches anyway), everything balanced, electric water and oil pumps to eliminate cavitation problems and to keep them from grenading at that speed, remove the altenator to keep it from destroying itself at those high speeds, who knows, maybe the CAS will become a weak point at those speeds and grenade, and I don't think a distributor would do any better, a new transmission rated to those speeds will be needed, driveshaft balancing and maybe a 2 piece one with a center bearing will be needed, and the list goes on.

So you see there's more than just the engine internals to think about. You'll need to treat every single rotating part to be able to handle those speeds and that'll cost a fortune.

Shoot for something more realistic, say 9-10k, and even that's challenging.