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semtex · 05-08-2009, 11:39 AM

Any chance that the extra gear in a 7AT is making a difference in temps? It is 7AT vs. 6MT, after all. I also agree with wstar that there may be differences in shifting behavior between the two. I know I sometimes have a tendency to leave it in a lower gear where I'm cruising with the rpms at 4k or higher, just because I want to have that instantaneous torque available. For example, maybe I'm anticipating that I'm about to open it up, so I opt to not bother with upshifting when I know I'll just need to shift back down a few seconds later. Or maybe I'm approaching a turn in 3rd gear. I'm going at a speed that warrants upshifting into 4th, but I leave it in 3rd with the engine wailing at 6000 rpms for a few seconds longer than seems natural because I know I'm about to nail the brakes and downshift into 2nd anyway. A 7AT isn't going to do that if it's left in D. In fact, even in manual mode, some drivers may not leave it in a lower gear like this, not when shifting back down is as easy as a flick on a paddle. (Plus they may actually enjoy flicking that paddle, right? So the more flicking that's necessary the better.) Well, over the time of a, say, 20-min spirited drive, my habit of leaving it in a lower gear in anticipation of an upcoming need for torque is probably going to translate into additional heat, and it'll add up quick, especially if I suddenly hit traffic and lose the cooling ability of free air flow to the radiator.

But having said all that, I have yet to see my temps go over 245. At the same time, however, I'm lucky enough that I have yet to run into heavy traffic at the tail end of a spirited drive. So take from this what you will.

05-08-2009, 11:39 AM	#419 (permalink)
semtex A True Z Fanatic Join Date: Jan 2009 Location: Behind enemy lines Age: 54 Posts: 5,995 Drives: People to drink Rep Power: 32	Any chance that the extra gear in a 7AT is making a difference in temps? It is 7AT vs. 6MT, after all. I also agree with wstar that there may be differences in shifting behavior between the two. I know I sometimes have a tendency to leave it in a lower gear where I'm cruising with the rpms at 4k or higher, just because I want to have that instantaneous torque available. For example, maybe I'm anticipating that I'm about to open it up, so I opt to not bother with upshifting when I know I'll just need to shift back down a few seconds later. Or maybe I'm approaching a turn in 3rd gear. I'm going at a speed that warrants upshifting into 4th, but I leave it in 3rd with the engine wailing at 6000 rpms for a few seconds longer than seems natural because I know I'm about to nail the brakes and downshift into 2nd anyway. A 7AT isn't going to do that if it's left in D. In fact, even in manual mode, some drivers may not leave it in a lower gear like this, not when shifting back down is as easy as a flick on a paddle. (Plus they may actually enjoy flicking that paddle, right? So the more flicking that's necessary the better.) Well, over the time of a, say, 20-min spirited drive, my habit of leaving it in a lower gear in anticipation of an upcoming need for torque is probably going to translate into additional heat, and it'll add up quick, especially if I suddenly hit traffic and lose the cooling ability of free air flow to the radiator. But having said all that, I have yet to see my temps go over 245. At the same time, however, I'm lucky enough that I have yet to run into heavy traffic at the tail end of a spirited drive. So take from this what you will. __________________ "There are no small accidents on this circuit." -- Ayrton Senna 316.8whp & 248 ft/lbs (Dyno Dynamics) \| 319whp & 256 ft/lbs (DynoJet) (04/23/10) Stillen G3 CAI, CBE, Pulley / F.I. LTH / GTSpec Ladder Brace / Setrab Oil Cooler / UpRev-tuned by Forged Perf.