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View Poll Results: Have you ever hit the rev limiter?
YES 147 67.12%
NO 72 32.88%
Voters: 219. You may not vote on this poll

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Old 11-22-2020   #151
Paul Workman
 
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Location: Squires (near Ava MO in the Mark Twain N'tl Forest) - Missouri
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Default Re: Poll: Who has ever hit the rev limiter?

Well, in a stock motor, one starving for air, BTW, POWER does dip before the 7100 red line. In fact sources including "Mr. Jingles" (one of the (former?) test drivers for GM said he power shifts the ZR-1s @ 6200.

But, your right after the shift puts you right on top of the torque curve and behind the power peak as it is ramping up again.

Porting the LT5 - even (as I am) running stock cams, really turns the BEAST loose, and then the LT5 is just on the crest of the power curve (on a 5.7L motor). Add regrinding of the cams and some judicious phasing and you'll need to reset the cutoff to 7500 or 7600 or more to appreciate what the motor will deliver.

But, you don't have to take my word for it...ask Pete Polatsidis who ran his 5.7L LT5 to the low 11s on a regular basis before dropping in Kevin Costelos' 441 LT5 (that Pete also built).

Pictured are some more or less typical (inertia) dyno graphs showing the before (stock) and after (ported) results. Note the stock engine was cut off at ~ 6300 rpm, but the HP is just seen to be ebbing even then. And, the ported LT5 (before and after) shows the HP is at its crest at the 7000 rpm mark after porting; a significant improvement!
Attached Images
File Type: jpg Stock LT5 dynojet Don Yokum.JPG (74.2 KB, 85 views)
File Type: jpg Don-DominicDynoCompar1A.jpg (36.1 KB, 79 views)
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Last edited by Paul Workman; 11-22-2020 at 09:42 AM.
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Old 10-05-2022   #152
Subfixer
 
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Location: Groton, CT
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Default Re: Poll: Who has ever hit the rev limiter?

After my 415 build, I found the limiter pretty quickly. Mark did not change the upper limit.
This thing revs so fast, I wasn't ready.

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Old 10-10-2022   #153
tiegsd
 
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Default Re: Poll: Who has ever hit the rev limiter?

Can't say I ever have, try to shift before 6K or so when I'm trying to blow the carbon out. Near stock power is just fine for my driving profile & level of driving skill.
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