redlining question

TuRbOtEcTicS

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Mazda3
yesterday i was driving home when i saw this rsx beside me and started revving at me. i started revving back and we approached a green light slowly and waited until it turned green (this was at 1am.) Any way it turned green and we launched off the line and all of a sudden i see the rpm at 7,000 then it went to 8,000 just to see what happens then i hear like piston cumbustion like sound from my engine and comming out of my exhuast. Just want to know if i hurted something or if i cause any damage.
 
so u went to 8k rpm just to see what happened? smart, u probably just hit fuel cut, i heard that's what happens in proteges when you hit 7200 rpm
 
yea, you blew the motor!, nah should be ok, just do not do it again, and i would check compression just to be safe...
 
if you are mechanically inclined at all, check your valves also, overreving sometimes will result in a bent valve, although if your car isnt smoking at all then you should be ok.
 
i doubt from one time doing that you hurt anything but dont do s*** like that. redline is there for a reason.
 
its not smoking at all. how would i check my compression? Im trading it in sometime next year any way so im not too worried about it.
 
search board for more in depth info but quickly, just buy an engine compression checker and it will have directions...they are pretty cheap, all you have to remove on the engine is the plug wires to check it..
 
Bouncing off the rev limiter won't do too much damage, especially if it has only happened that once.

I don't think it actually ever goes to 8k either, I believe it cuts in around 7200k.

That being said, I've bounced off it a few times, and the baby just keeps coming back for more ;)
 
even with a rev limiter, sometimes people WILL over-rev past that in certain instances, never gone near a rev limiter myself except when i 1st started goin to the track a while back(2 years?) and hit it doing burnouts(can hold a good burnout at around 5k now that i know how to do it) but sometimes it will happen and is bad..
 
Over-revving even once can greatly reduce the tensile strength of your rods and the problem usually won't show up until much later down the line when the motor will pop and you'll be wondering why exactly, not remembering the over-rev incident.

Seeing as how you didn't peg it to 10k I wouldn't worry about it much.
 
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just keep in mind that up to 7000 max, you are safe, but after 6500 rpm, you dont benefit in horsepower cause it's at that point where the engine stops producing sufficient power for the tranny to feed to the wheels, so keep your shifts between 6000 and 6500 rpm when racing your engine.
 
But unless your torque falls off by 50% above 6500 the mechanical advantage of the lower gear outweighs the higher torque produced by shifting to the next gear. To put it simply, you're still accelerating faster from 6500-7000rpm in 2nd gear than you are at any RPM in 3rd.

The engine STOPS producing power to feed the wheels? (rlaugh)Every dyno sheet I've seen must be wrong then, since they always show the engine still making power till the rev-limiter.
 
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That was really dumb...

This was due to High RPM...


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not to call anybody a moron.....but also keep in mind that you rev limiter does NOTHING if you happened to be an idiot and mishift/downshift from third (@6500rpm) to second (>8000rpm??).
 
you don't have to be an idiot to mis-shift, I guess you've never really raced
supershort shifter throw + quick shifting = easy mis-shift
 
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