There seems to be a sound comming from the engine at 6000 RPM on the dot at every shift. Sounds like a bell ringing or like load valves if the car had valves. The only thing i can think of is secondary intakes opening because i belive i read it has secondary port. Anywho help me out if ya know the answer or if ya have the same sound.

T o n Y

 

My Honda did that at 3000 rpm after I put on a new exhaust and header ... as far as I know, certain parts would didn't have a lot of clearance between the frame (or something else, who knows) and would resonate at that rpm (frequency). The bell sound is the metallic ringing as they vibrate rapidly against another metallic component. For me, it happens only in cold weather, so I'm guessing the contraction of metal parts due the cold only further serves to reduce clearances.

 

yer right, 5th and 6th intake ports open at 6250, and then another h-type valve opens at 7300? or so. if you listen closely, you should hear all sorts of valves open on the way up to 9500 rpm. although i've never been able to hear the one at 4k or so.

 

wow 6 ports, thanks for the info i feel much better now. I thought i broke something but im finding that the more you abuse this motor to more it loves it. Hats off to Mr Wankle.

T o n Y

 

I was wondering if anyone feels a wierd vibration at 650 rpm when the car is just sitting. just got my car and have 1500 miles on it.

all the info would help

 

650 rpm sounds too low... maybe your idle needs adjustment... although given the ECU... not sure if this is adjustable.

 

I also hear the "bell' sound at @6000 RPM. It has been decribed in past threads as a "metallic rattle" also.

The "Bell" sound is a very good way to describe it. To me it sounds like a bell in the distance.

I will add another caracteristic of this sound.

You wont hear it if you simply rev your engine in idle. There has to be a load on the engine/drivetrain.

I realise it is right at the RPM for the port open sequence, but if you listen, you can hold the noise at a constant. The fact that you can get the noise to occur for a long duration leads me to believe its not a port opening.

Also....not to add more doubt to the port theory, I think it was Speed Racer who had his clutch go. He brought it to the dealership and they said the clutch over heated and the springs in the clutch disc rattled around. When he drove the car after repair he noted that the "metallic Rattle" was gone.

 

there is another thread on this problem

https://www.rx8club.com/showthread.p...ight=thrashing

I have had the same problem and I drive an auto (no clutch). I had the sound a few times but ever since then, it stopped. I heard that sound when I first started to push the car to a high rpm, so I'm guessing it might be breaking into those high rpms.