spdspappy

I just found out something interesting yesterday... The engine is definitely rev limited & at about 13k RPM's the computer shuts itself down. I was at a dealer getting my oil changed yesterday and they said someone mis-shifted in one of their cars and the car had to be towed. When they checked the car on the computer, it said that it went over 13k. Can we say "new engine"? Ouch...

S3/P3/E2

I was under the impression that just as the car was "speed limited", that it was rev limited as well at the redline. Time to do some more reading I think...

Genom

If your doing 9000RPM in say 3rd, and down shift into second instead of 4th, and NOT catch yourself in time, you will severly over-rev the engine. The rotary is more fleixible than a piston engine in that regard, but still, 13000RPM? No wonder it died.

kristopher_d

The rev limiter kicks in at 9750. I know this 'cause I've occasionally gotten caught up cornerning and forgot to shift. However, down shifting too far would obviously force the car to over-rev even more. It makes little sense that the computer would shut itself off though. I guess Mazda want's to know when we REALLY abuse our brand new cars. At the same time, I beleive load and longevity testing on the Renesis were conducted at 13000RPM and 70% load for 72 hours with minimal wear, so the red line is really more about keeping things predictable. The biggest risk in over-reving a rotary is stressing the stationary gears. The old 13B's are good for up to 12-13K, and hardened gears can be installed during a rebuild that are rated for 16K rpm. Of course, you could also starve the rotor bearings of oil at that rpm too.

The reason piston engines tend to fail at high rpm is valve float. In precision engines, the piston face tends to crash into the valve, bending it, when the camshaft spins quicker than the valve springs can react.

S3/P3/E2

Thanks KD - I am now smarter than I was the other day...

Spinny 3ngls

I was told by a tech at the dealership that the renesis actually test to just over 14,000 rpm and then the only things that happen are that the water pump and the alternator self destruct. I dont know if it is anyone here but a friend of mine told me there is a person runnning a 3 rotor on the drag strip up to 19,000 rpm, so 13,000 may not have destroyed the engine maybe just the peripherials.

spdspappy

Wow, 13k sustained is pretty good...

rx-7~rx-8

Rotaries could rev like crazy... i know this is off-topic but how come SPOON engines in hondas rev to 14000 RPM... info on that please on GT3 the s2000 Spoon can rev to 14000 RPM... i know the RX-Evolve made 280PS at 10,000 RPM... so 10,00 isn't jack for renesis... it revs like no other.

Genom

Well, shows what I know :D

j1mb0x99

Maybe this is where the rx8's tuning lies. What is the power curve after 9K RPM? If it doesn't drop and stays somewhat linear wouldn't that mean more power? I don't really know about this factually, but it is an idea.

-JiM