Rear Ends
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From: JawJa
Rear Ends
Could someone please explain the difference in the 2.56 (current) axle and the proposed GU2 - 2.73 (A6). Some said 3.15 or 3.42? was best in the A4. Is it good or not good? What is the best case scenario. I'm not knowledgable in this area. Thanks.
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St. Jude Donor '05-'06-'07-'10
) from a performance standpoint came from the 2.73 automatic. There was a performance axle option in the C5 Automatics that made the car seem a little "faster" off the line. This was a 3.15. The current Manual is the 3.42 and was in the C5's as well. Basically, the higher the ratio the faster the engine will rev at a particular vehicle speed. This ratio is usually described by the multiplier such as the 3.42 but actually is indicative of a comparison of 3.42:1 or 3.42 to 1. this is the number of turns from the final drive it takes for one turn of the wheel (axle.) This will be further multiplied or reduced by the transmission gearing.
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From: JawJa
Speaking from the C5 numbers the "worst" (if there can be a worst in a Corvette ) from a performance standpoint came from the 2.73 automatic. There was a performance axle option in the C5 Automatics that made the car seem a little "faster" off the line. This was a 3.15. The current Manual is the 3.42 and was in the C5's as well. Basically, the higher the ratio the faster the engine will rev at a particular vehicle speed. This ratio is usually described by the multiplier such as the 3.42 but actually is indicative of a comparison of 3.42:1 or 3.42 to 1. this is the number of turns from the final drive it takes for one turn of the wheel (axle.) This will be further multiplied or reduced by the transmission gearing.
) from a performance standpoint came from the 2.73 automatic. There was a performance axle option in the C5 Automatics that made the car seem a little "faster" off the line. This was a 3.15. The current Manual is the 3.42 and was in the C5's as well. Basically, the higher the ratio the faster the engine will rev at a particular vehicle speed. This ratio is usually described by the multiplier such as the 3.42 but actually is indicative of a comparison of 3.42:1 or 3.42 to 1. this is the number of turns from the final drive it takes for one turn of the wheel (axle.) This will be further multiplied or reduced by the transmission gearing.Last edited by GotVett?; Feb 11, 2007 at 12:58 PM.
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I believe it would have been necessary given the gearing in the 4 speed auto to allow for comfortable cruising at highway speeds. The lower gears are taller in the auto to give it some get up and go but it only has four gears to balance out when up at highway speeds. It would seem to find a balance between the two is what they were after (I'm sure fuel economy came into play as well.)
