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Looking for a clarification on the redline and the shift indicator light. I understand the redline is 8000, with a "floating" redline of 8500. I gather the floating redline is for short bursts only, whereas the 8000 can be sustained.

So what is the indicator light supposed to be telling me? I know it comes on at redline, but isn't it supposed to be telling me optimal shift points, too? I haven't redlined my car, but I've had it up to about 7K, and I haven't seen a light yet. Should it be coming on at some point below redline?

Yes, I know I'm showing my ignorance here.
;)
 

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It will come on as you approach redline. Do it when the engine is not fully warmed up and it lights up a lot lower. :)
 

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Anyone know for sure the details of the briefly higher redline? Officially it's 8500 RPM for 1.5 seconds, but I have heard that about 8600 is the actual limit. In either case, that is up there!
 

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shift indicator light is programmed to light up at the recommended revs where you shift up and they will fall into the meat of the power band for another burst of acceleration.

The rev limiter will put a stop to the giggles as the factory definition of max recommended engine speed.

Downshifting... you're on your own, it is not programmed for downshifting although some aftermarket units are..

1.5 seconds of extra engine acceleration will only be useful if you absolutely know the track and could use the time to avoid a time wasting upshift. Otherwise why risk damage.
A lot of these engines have been destroyed in the donor cars from missed shifts....off course the muppets put it down to a reliability issue.

I don't really see the factory's point of advertising this feature.
Really keen drivers will discover it on their own, while most of us mere mortals will shift when the light pops on.
It is probably past its power peak at 8500 revs anyway.
Pinmagic, If one were to plot a gearing to torque chart, the revs at which the light illuminated would be apparent.
m.
 

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>>>It is probably past its power peak at 8500 revs anyway. <<<

Doesn't really matter....basically you stay in a given gear until it's advantageous to be in another. So if by going to 8600 the power is way down yet the acceleration is still better than at whatever RPM the next gear would provide with it's taller ratio it was worthwhile. The key is thrust at a given moment. Ignoring corners for the moment.
 

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totally offtopic here but....
I watched the Monza F1 race today (twice!) and was wandering how they can get those engines to upwards of 19000 RPMs! How does the engine have enough time to inject fuel into the cylinders, burn and exhaust at such speeds? If anyone is knowleadgeable about these engines please shed some light!
 

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On misshifts: What kind of valve damage history does our engine have with Celica owners? At what RPM does interference occur?
 

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>>>On misshifts: What kind of valve damage history does our engine have with Celica owners? At what RPM does interference occur?<<<

Like any modern engine the 2ZZ-GE has a rev limiter. But this won't prevent a mechanical overrev - hitting say 2nd instead of 4th when shifting from 3rd at redline. In such a case the RPMs will hit roughly 50% higher than redline. This is way too high to survive unscathed...stiffer valvesprings or whatever won't help. A fair number of the early Celica GT-S motors grenaded due to things like that.
 

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Stan said:
>>>On misshifts: What kind of valve damage history does our engine have with Celica owners? At what RPM does interference occur?<<<

Like any modern engine the 2ZZ-GE has a rev limiter. But this won't prevent a mechanical overrev - hitting say 2nd instead of 4th when shifting from 3rd at redline. In such a case the RPMs will hit roughly 50% higher than redline. This is way too high to survive unscathed...stiffer valvesprings or whatever won't help. A fair number of the early Celica GT-S motors grenaded due to things like that.
As Stan has said, If you miss an upshift , the rev limiter will typically protect the engine from damage. The car is typically not in gear if you miss an upshift.

If you miss a downshift, or you miss shift and hit a lower gear while accelerating, you ARE in gear and the drivetrain will be accelerating the engine... the ECU cannot protect against the sheer physics and inertia of the engine, gearbox and tires.

As much as 3000-4000 rpm gain in drivetrain speed with 1-2 k past max engine speed(way past redline and rev limiter) will cause bent valves at a minimum, and a ventillated block via an escaping con rod is usual.

The Celica GTS evidently has a sub par shift quality, so engine damage caused by user error is not a reliability problem of the powerplant.

It is a loss of interference caused by component failure.
1, the engine speed is enough that forces within components cause component failure, eg a connecting rod gets bent, or a connecting rod bolt shears.
2, the mechanical timing apparatus... belt, chain, loses track and destroys the timing of the cam(s) and crank.
3, certain destructive resonances are tuned to occur at speeds that the engine does not typically see. These will tear the engine apart if it is run however briefly, at those speeds.
4, All metals have some elasticity to them and need time to stretch and retract in order to live. eg. the crank... it is flexing in there when the engine is operational.
m.
 
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