Interesting Sedan vs Coupe data from Infiniti back in 2002
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Interesting Sedan vs Coupe data from Infiniti back in 2002
http://www.thecarconnection.com/Vehi...184.A5395.html
Interesting. Finally an explanation has to where the supposed extra 20hp/10tq came from. The coupe vs sedan dynos don't seem to support it though.
Interesting.
Confirms what I thought about the TC in the 5AT. It locks at a certain rpm at full throttle. Most TCs will remain unlocked at full throttle because it's easier on the TC, but it also bleeds power. This would explain why the 5ATs seem to run pretty good for having an auto (compared to other similiarly powered automatics like the TL) and typically post pretty strong mphs in comparision to the G 6MTs.
In the G35 Coupe, the dual-overhead cam, 24-valve unit produces a robust 280 horsepower and 270 pound-feet of torque, 20 horses and 10 lb-ft more than the version found in its sedan sibling. (Only the Z's 287 hp and 274 lb-ft top it.) "The coupe's exhaust has half the back pressure of the sedan," Crahan told TCC, "that was the start of the domino to get from 260 to 280. Once that was done, we could change the variable valve timing to the intake to reduce the pumping loss, balancing the pressures on both sides of the engine and providing better breathing throughout."
Although sharing the sedan's 112.2-inch wheelbase, the coupe is four inches shorter in length and 3.1 inches in height, but is 2.6 inches wider. In fact its 71.5-inch width is the same as the Z's, and not by accident, for it shares the Z's wider rear suspension arms (part of the multi-link setup)
Although we prefer the six-speed, those opting for the automatic can experience many of the same sensations thanks to some nifty attention paid to its torque converter. Once in your selected gear and above certain rpm, it locks, not shifting up or down. Accomplished via software programming, it sounds simple, but the effect is amazing. You feel as if you're actually driving a manual, both from sound and sensation.
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Once that was done, we could change the variable valve timing to the intake to reduce the pumping loss, balancing the pressures on both sides of the engine and providing better breathing throughout."
not sure how that works, but how can the sedan overcome that to pick up part of the difference in power ? Custom tuning ?
not sure how that works, but how can the sedan overcome that to pick up part of the difference in power ? Custom tuning ?
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Originally Posted by DaveB
Interesting. Finally an explanation has to where the supposed extra 20hp/10tq came from. The coupe vs sedan dynos don't seem to support it though.
It could also be how the fuel was mapped for the sedan. In the owners manual, the 02-04 sedan with 260hp required 87 octane but 91 was preferred. The 03-04 coupe always had 91 required. Nonetheless, very small differences in performance.
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So about the TC on my 03 AT, is this the reason why when ever I punch it @30mph it does not downshift? RPMs jump to about 2500, it just sort of stays there for about 1-2sec and then goes? or do I have a TC problem?
Originally Posted by DaveB
Although sharing the sedan's 112.2-inch wheelbase, the coupe is four inches shorter in length and 3.1 inches in height, but is 2.6 inches wider. In fact its 71.5-inch width is the same as the Z's, and not by accident, for it shares the Z's wider rear suspension arms (part of the multi-link setup)
noted Thomas Crahan, manager of product planning
Of course the coupe and Z are lower, they have lower ride heights and are styled that way. Both car's have wider widths not just because of style, but because they have wider fenders vs the sedan. He also forgot to mention that the coupe and Z get under car chassis bracing that the sedan doesn't get (tunnel stay's and pin stay), plus the coupe and Z have a much more massive front brace setup that ties in the lower control arms to the mid section of the car. I'm not suprised that someone associated with the company would say the wrong thing, early in 2003 a member of the Z33 suspension developement team talked a little too much at a car club meet in Japan, some of what he said turned out to be correct, but some of it was not.
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