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Hey,
Just purchased 2005 Victory Red, XM, OnStar, Sunroof....awesome car!!! Although my buddies keep teasing me that I bought a Cavalier! I just tell them to drive it and it shuts them up!

Anyway, I have been good so far on really pushing the car accelleration wise, trying to ease into....but I was at a light and decided to give it hell....I went through first gear so fast!!! I was bouncing off the rev Limiter!! Freaked me out!!! I felt guilty as hell.....I have driven a stick for years, I think it just surprised me how fast you go through first!!! Do you think I could have damaged anything?? Don't want to blow the supercharger or engine right off the bat...thoughts!
 

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Naw, the rev limiter should protect your engine.unless you're pounding the rev limiter constantly for like 2 mins straight.
 

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Ad Man said:
Hey,
Just purchased 2005 Victory Red, XM, OnStar, Sunroof....awesome car!!! Although my buddies keep teasing me that I bought a Cavalier! I just tell them to drive it and it shuts them up!

Anyway, I have been good so far on really pushing the car accelleration wise, trying to ease into....but I was at a light and decided to give it hell....I went through first gear so fast!!! I was bouncing off the rev Limiter!! Freaked me out!!! I felt guilty as hell.....I have driven a stick for years, I think it just surprised me how fast you go through first!!! Do you think I could have damaged anything?? Don't want to blow the supercharger or engine right off the bat...thoughts!
It's a 2.0 litre also. It seems like it could easlily rev to over 7000 rpm. I cannot wait for CPU upgrades!!
 

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SS4ME said:
It's a 2.0 litre also. It seems like it could easlily rev to over 7000 rpm. I cannot wait for CPU upgrades!!
It might take quite a bit more than just a PCM upgrade to rev up that high. GM is notorious for using cheap valve springs, I would swap them out for a better set before I rev'd one of their motors up that high. Not sure if the SS has a non-interference engine or not, but I would not like to find out the hard way if the valves started floating.

The dyno plots I have seen have the torque falling on its face around 5500RPM, It looks to me that either the springs have given up or the cam is too short for high RPM running. GM heads have been very decent in the last 10 years, so I imagine they flow well enough for high RPM.

I suppose it is possible that the PCM is artificially limiting power above that point, but I would not trust the stock springs until someone proves they are up to the task.
 

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Digdug, you may be right on your point. It just seems like the car has more beef up top then the rev limiter gives you. It seems like it is cutting you off 500 rpm too early.
 

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Discussion Starter #6
thanks for info all.....didn't want to damage the baby so early on in its life!! It does seem like the RPMs should be higher for such a hi-reving engine!
 

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I did the same thing when I test drove mine. I'm use to my 90 Silverado truck which is slow to accelerate and shift. And I'm a lead foot coming from my 85 Corvette, so 1st was over and done with faster than you could blink.
 

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i own a 05 Redline and i have looked in to this problem and it seems like the engine is too fast for the tach. In first the tach is 800RPMs behind the engine and in 2nd it in around 400RPMs behind but the rest is ok. I was freaked out the first time i did it to.
 

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Ron9919 said:
i own a 05 Redline and i have looked in to this problem and it seems like the engine is too fast for the tach. In first the tach is 800RPMs behind the engine and in 2nd it in around 400RPMs behind but the rest is ok. I was freaked out the first time i did it to.
Do you know if they fixed that from the ION R/L to the Cobalt SS's tho? Cause I heard that problem about those redlines when they came out...have they fixed it since then?
 

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DigDug said:
It might take quite a bit more than just a PCM upgrade to rev up that high. GM is notorious for using cheap valve springs, I would swap them out for a better set before I rev'd one of their motors up that high. Not sure if the SS has a non-interference engine or not, but I would not like to find out the hard way if the valves started floating.

The dyno plots I have seen have the torque falling on its face around 5500RPM, It looks to me that either the springs have given up or the cam is too short for high RPM running. GM heads have been very decent in the last 10 years, so I imagine they flow well enough for high RPM.

I suppose it is possible that the PCM is artificially limiting power above that point, but I would not trust the stock springs until someone proves they are up to the task.
Not sure what dyno graphs you've been looking at. Every one I've seen has showed maybe a 10% drop in torque from 5500 to 6500. Power curve is still on an upward trajectory at 6500. Maybe you've been looking at 3800 pushrod dynos by mistake. :)
 

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DanM said:
Not sure what dyno graphs you've been looking at. Every one I've seen has showed maybe a 10% drop in torque from 5500 to 6500. Power curve is still on an upward trajectory at 6500. Maybe you've been looking at 3800 pushrod dynos by mistake. :)
Not to mention if it was "float" as suggested, it would be pretty difficult to continue to making the HP right up to 6500 like it DOES! I've hit the rev limiter often enough- never HEARD em float though.
WOT
 

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i really dont know if they fixed it from the RL to the SS but if he is having that problem then thats what it sounds like
 

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I was playing around with a WRX on I35 this morning and hit the limiter running 3rd gear out... Scared the $hit out of me :eek:
It was amazing though how fast it picked back up after hitting 4th gear.
Got to really keep an eye on the tach, or get a louder exhaust :D
 

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redlineRACER said:
or you can get an aftermarket tach and shift light...there awesome... :D
Yea both cars are using a "network" tach, receiveing an RPM packet sourced from the PCM.The Cobalt may have less lag though, as it's using the faster GMLan (CAN) and the Redline is PCM is Class 2. I think both cars would benefit from a direct connect tach, it would probably make it more responsive.

There's no physical TACH wire from the ingnition system on the LSJ.
Someone on the Redline forums said they had success connecting to one of the Ignition Control circuits between the PCM and the COP modules- but who know what effect the added electronics of the tach might have on the timing control circuit performance. Maybe you can tap C1/pin 31 used by the ladder tach on the Redline to get a tach signal?
WopOnTour
 
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