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Originally Posted by USAZR1
No,it isn't. Take two ZR-1's,one with 3.45's and one w/4.10's,both same tire diameter. Shift both cars into high gear at 80mph. Both cars will drop the same rpm? No,they will not.
At any given speed or gear selected,the 4.10 rear will be spinning the engine faster. Why is that so hard to understand?
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In an attempt for comprehension as the internet excises 75% of our communication ability. I dont mean to fan any flames here.
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You are referencing vehicle speed, when we were talking about engine rpm difference during an upshift.
If you have your 4.10 gear car, and I have my 3.45 rear gear car, in 1st gear you wring your LT5 to 7500rpm, and I wring my LT5 to 7500rpm, we both throw a powershift into 2nd gear. What are out tachometers reading? All else not mentioned in the above scenario equal, our tachs will read the same RPM once our ZF's are in 2nd gear.
RPM drop can only be changed with transmission gear ratio changes. Speed vs engine rpm can be changed via trann gear changes, rear end gear changes and tire diameter changes.
I have never heard "RPM drop" referred to in a fashion to which you have described. To calculate a shift RPM drop, you must 1st have a Before RPM and a Resultant RPM. Shifting a 3.45 vs 4.10 car into high gear at 80mph tells you nothing of rpm drop, but will surely give you the engine rpm of each car, or which, the 4.10 gear car would be revving higher, all else equal. But if you are shifting from 3rd gear to high gear in both cars, the rpm drop in BOTH the 3.45 and 4.10 gear car will be 100% the same.
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At any given speed or gear selected,the 4.10 rear will be spinning the engine faster. Why is that so hard to understand?"
You are describing a difference in overall final drive ratio which combines trans ratios AND trans ratios. Of course the 4.10 geared car will rev higher- all else equal, but this relates to rpm at a speed, not rpm drop as it relates to trans gearing. Regardless of rear gearing, rpm drop during shifts will be 100% the same as trans ratios are the same-all else equal.