Originally Posted by
Epstein
Eh, not the same. The first cammed one drops 125tq by redline which is 27% of peak. The second drops about 80tq, only 15%.
Tq drop-off isn't that bad as long as your drop-off ratio isn't greater than your next gear. Then you're in that situation where short shifting it makes it faster. Tq drop charts also have a pile more area under the curve than a flat chart if you compare peak HP numbers. That's why your cammed GTO plot is roughly equal to my old S13, even with 10% power difference. Area under the curve.
The tq number really doesn't mean as much as you think. Yeah, you might have 450tq versus my 330tq, but you're pushing through taller gears and shorter redline. Your first is 2.97x3.54, mine was 3.321x4.363. Multiply that out and the wheel torque is roughly equal! The down side is that because the overall ratio is shorter, I'll run out of gear faster. The difference is about 35% faster for me to run out. This is countered by my 15% higher redline (8k vs 7k). So the GTO setup adds to be more, but not by the amount of the tq difference. This is all in the spreadsheet. It's like staring at the matrix.
I'm glad to see that these big displacement motors can actually make the power!
So is that a 4k stall that's responsible for that bump in the chart?
Those cars werent available auto, its stick
It does mean what I think, its that I can have similar acceleration to a large turbo'd SR, while maintaining a car that doesnt have any sort of turbo lag, and cruises at low rpm, dont forget I can easily swap in that 3.69 or 3.91 ratio, for track events
And like I mentioned, if you wanted a flatter more rshared_pm biased curve, the cams are available for it
Heres one on a stock ci, stock headed LS1 346 ci, vs the 6.0's 364 ci, these are unported stock heads on it also.
Keep in mind, none of these have gotten into ported heads, the previous dyno's other than the LS7 one, were very mild cams, this last one is something a little more RPM biased, still on a hydro roller lifter, and something some people consider daily driveable
