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red lining at 120 in final gear, help...

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Old Aug 9, 2010 | 10:02 PM
  #1  
Shivo's Avatar
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From: Florida
red lining at 120 in final gear, help...

Currently running my 96 z28 LT1 with a 4L60E transmission b/m shift kit
installed. I haven't installed a tuner, but i'm unsure if the prior owner ever
used one.

The problem is my camaro reaches 120 fast and then red lines while in the 4
th and final gear. can I use a tuner to stop that? can I bypass that? or
should I just upgrade to a better transmission? (please, keep in mind I want
to stick with an automatic)

suggestion?
Old Aug 9, 2010 | 10:07 PM
  #2  
dangalla's Avatar
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From: lakeville, pa
this is not advanced tech material

what do you mean that it redlines - does it just stop wherever the rpm's are when you get to 120 or that is where the tach gets to redline

why do you need to go faster than 120 anyway?
Old Aug 9, 2010 | 10:09 PM
  #3  
Shivo's Avatar
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From: Florida
sorry, where should i post this?

I'm trying to get this above 120 faster. it's for drag racing purposes.

and it hits the red in my rpms once it reaches 120, then it continues
in as i continue to accelerate.
Old Aug 9, 2010 | 10:28 PM
  #4  
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Its hard to figure where this post to, because the problem is not very clear. From your second post, it appears that the tach needle enters the "red" zone on the tach face when your car is going 120 MPH in 4th (O/D) gear. This is basically impossible.

Stock rear axle ratio on an LT1 with a 4L60E is 2.73 or 3.23. Worst case scenario, with 3.23:1 gears, the engine would be at 3,550 RPM, well below redline (approx 5,700 RPM). Even with 4.56:1 gears, it would be turning only 5,000 RPM, still below redline.

If the engine is turning about 5,700 RPM at 120 MPH in 4th gear (O/D), the trans is slipping badly.

Clarify what you mean by "and it hits the red in my rpms once it reaches 120, then it continues in as i continue to accelerate." If it hit redline in 4th gear, what happens when it "coninues in"? Totally unclear.

Is it possible you mean the engine has the fuel interupted at approximately 120 MPH? That would make sense, because unless the vehicle left the factory with Z-rated tires, the stock top speed limiter is programmed as 118 MPH.
Old Aug 12, 2010 | 09:33 PM
  #5  
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From: ABQ, NM
Injuneer, i bet your right about the fuel cut on this one. OP probably saying the car "bucks" like its bouncing a rev limiter. There is a value for fuel cut in the tune that needs to be changed.
Old Aug 12, 2010 | 09:51 PM
  #6  
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From: Hell was full so they sent me to NJ
I don't think it matters much - he hasn't been back to the site since his second post on 8/9.
Old Aug 13, 2010 | 09:44 AM
  #7  
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From: Florida
injuneer, you were right. the top speed limiter was programmed at 118. my buddy happened to be an lt1 tech, helped out with fixing the 'problem'.

Apologize for the confusion. when i said it continues in, i meant the tach needle continues to show higher rpms on the tach face.

wish I had logged in wednesday, would have helped figure out what the problem was faster. thanks.
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