want to raise rev limit
- Thread starter cowpatty
- Start date
These questions absolutely amaze me.
Dali Hot Chip. It'll raise the rev limiter a few hundred.
cowpatty said:
Have you dyno'ed your car to see how torque is bahaving at your redline? If torque is falling off like a normal NSX motor, then you will probably not gain anything performance wise (no more HP). Also do you have any aftermarket engine internals that have reduced the weight of the rotating assembly (pistons, valves, flywheel, etc??).
To get any real gain from a heightened redline you need to be maintaing your torque curve to at least your current rev limiter. Which can be done by choosing high RPM engine parts. And you need to reduce the weight and or change the geometry of the rotating assembly so that you do not get overly increased engine wear.
An AEM EMS would be the best way of raising the rev limiter (more) safely.
Would this http://www.comptechusa.com/store/510175.html
make it worthwhile for an SOS ECU chip with the raised rev limiter?
I also have and the CAI intake and Flowmaster 1-chamber muff exhaust. Will that combo be benefitted from the raised limiter?
make it worthwhile for an SOS ECU chip with the raised rev limiter?
I also have and the CAI intake and Flowmaster 1-chamber muff exhaust. Will that combo be benefitted from the raised limiter?
A lighter clutch/wheel is a descent start to having the ability to rev higher. Generally the intake tract and exhaust systems are not what limit the ability of the engine to breathe at the top end of its RPM range. Its usually the intake manifold design, the camshaft design, the shape of the ports in the head, the valve's, and the header design.
Basically in an engine all your trying to do is fill the capacity of the engine at any given RPM (3.0L in your case) with air and fuel. The engine does a better job of doing it at various RPM ranges. Thats why the torque builds at lower RPM's and then eventually will level out through the mid-range, thats where the engine is filling as much of engine as it can with air (but still not 100%). Then as the RPM's increase, because of the design of various parts it gets harder and harder for the engine to fill the same amount of air into the engine thus effeciency goes down and torque goes down, because you mixing less air and fuel.
So imagine an engine like a downtown city and the intake and exhaust pipe are like the highways going in and out. If the inner city roads are slow and congested then it won't matter how big the highways are, its the city thats going to cause the backups.
Thank-you, I did go ahead and buy the chip today. Not so I can run it to that everytime but I also have the http://www.comptechusa.com/store/product1234.html
and quite often I bounce off the limiter just before I can shift. Maybe now I can shift smoother because I have a lil more time. I'm of course also hoping the chip actually gives a few horsepower too.
I have the Dali Hot Chip and love it. Only raises the limiter by 200 RPM but you don't have to concentrate so hard on shifting right at 8,000. You get a little play up to 8,500 and the engine feels great up there.
I would be careful about reving the engine too high with disabled rev limiting. I forget where & when but I had inquired as to what was the limiting factor on the NSX engine having owned a Honda motorcycle that had a redline of 8000 rpm but never has been damaged by smoking the tires in 1st gear (which had the engine spinning at 10,500 rpm) or seeing the tach fly past 12,000 on mis-shifts while drag racing (hate them false neutrals on motorcycle transmissions). The CB750K never floated a valve to cause the kiss of death at these extreme RPMs. So I felt the NSX engine was likely similarly robust in design. The answer I got surprised me. The oil pump can't take the pressure it will generate at rpm's in excess of redline. I didn't get a specific answer as to what rpm will cause it to fail, but was told it is likely <9000. There are aftermarket oil pumps for those that are making serious engine mods that want/need higher rpm. Maybe someone else has more specific knowledge as my info is defintely 3rd party and I can't recll the source although I'm pretty sure it was here on Prime.
That's true. Although I love being able to go to 8,500 rpm the engine is under enormous stress at that speed and I would never, ever exceed 8,500 rpm. Disabling the rev limiter altogether is a very bad idea. See this thread:
http://www.nsxprime.com/forums/showthread.php?t=81540
