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The Beast has a 2.92:1 rear gear ratio.
The bigger the number before the :1, the faster you accelerate... Within reason.
The problem with thinking this way is there's something with ratios on the other end of that driveshaft.
The Beast, in first gear will spin the engine 11.76 times for every time the rear tire spins once.
That's actually pretty deep.
The Biscayne with a 3.08 rear gear was just 9.42.
Marv dropped a very deep 3.73 rear in his Impala SS and rocks a 11.41. That's not as good as The Beast!
There's lots of people who're putting 3.27 and 3.56 rears into their Caprice PPV's. The complete differential from a 5th Gen Camaro bolts right in.
I wonder if that's too deep. Sure the launch is epic, but you're grabbing for 2nd gear way too fast and losing all the benefit. You're in the redline by 40 with 3.27; 30 with a 3.56.
2.92 is not hitting red until past 40.
The Camaro rear has a larger diameter ring gear. That's more durable.
There's a lot more math to crunch.
The people who've done this tend to be in the "I got the best 1/4 mile time!" groups and are willing to sacrifice mileage and driveability for the time.
Not so much for me.
Super light cars and overdrive transmissions can mitigate a LOT of compromises here. And that's before we get into time honored work arounds like quick change rear ends. ;) Nothin says "not screwin around" like pullin in to the strip and swapping out your highway gears for the race gears in your box.
ReplyDeleteIt's a tightrope, indeed.
ReplyDeleteIf I launch hard, and there's a cop around, I get a ticket for "Deliberate loss of traction", or "excessive noise", or "racing", so excessively low gearing is problematic.
If I launch sedately, but venture into higher RPMs in higher gears, and there's a cop around, I get a ticket for "excessive speed", or if more than some specified amount above the limit, the car is confiscated, and I go directly to jail, so excessively high gearing is ALSO problematic.
To add insanity to injury, a cop once tried to issue me a speeding ticket while I was riding a bicycle!
I am yet to determine the sweet spot for final drive ratio, but since I can't afford to swap out the transaxle, I guess it doesn't matter. :)
On the other end of "car modding" people, you have me with 4.88's on my '97 jeep. The 51:1 crawl ratio I wish was a little slower when I'm in the rocks, but I want to keep it drivable on the interstate. Even so, I often find myself considering 5.13 or 5.38s. But as it sits currently, I'm shifting out of first around town at 15mph, usually before I make it across the intersection. That usually reminds me that 4.88 is a good compromise for my use.
ReplyDelete