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Discussion Starter · #1 ·
97 RZ 6spd, stock jdm factory twins, stock jdm fuel, PWR fmic, full 3" exhaust, ported head, custom cams, motec m600

power


torque
 

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Slow Poke
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Nice, who did the custom grind cams for you? where? how much? ;)
 

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T-Power
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hold on 327rwhp and 681 ft-lb of torque? :scratch:
 

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Discussion Starter · #8 ·
Stu Hagen said:
Ya I could never figure out the conversion on torque, maybe Ben can expain.
i have no idea. i asked the tuner (who does a lot of work with the v8 supercars over here in australia). he was really impressed with the torque and midrange power, something he hasn't seen before on a turbo car. he had a v8 chevy on the same dyno after mine, it made just over 500ftlb peak torque

in the car it is very noticable, if you floor the throttle above 3000rpm in 1st, 2nd or 3rd gear the tyres can't hold (275/40/17 falken azenis rt615)

have to be a bit gentle with the go pedal...
 

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I still don't understand the torque number. Simple physics does not change, even down under.

By definition, torque and hp are not independent, they are not two different measured numbers. If you know one you always know the other one by simple calculation. By definition it is always according to:

HP = TQ (ft-lbs) X RPM divided by 5252

From the charts above, if the tq is 681 ft-lbs @ 94kph (3918 rpm according to the chart) then hp at that engine speed or rpm should be 508hp. So they why does it say power at 94kph is only 245hp? (which by definition would be 327 ft-lbs @ 3919 rpm).

Something's wrong with those numbers.
 

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I seems to me they had the tach signal reading 2 times the rpm's and that is what gave it the high tq reading. I have seen it done on a dynojet before.
 

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Klop said:
...they had the tach signal reading 2 times the rpm's

oh oh ...I better stop telling people my 2JZGTE revs to 14,000rpm :ugh2:
 

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Latteboost said:
I am assuming at the 5820 is RPM on the x axis. If so something is weird as the hp is much less (327 vs 620) than the torque. No matter what your HP number will always be higher than you torque number (ft-lb) above 5252 RPM.
That is why it looks like the RPM signal was not set up right for the dyno pull. Maybe they had set it up for a rotary. It would show 2 times the tq actual numbers.
 

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Discussion Starter · #14 · (Edited)
you have to remember that the torque figure from a rolling road dyno is a function of several factors including wheel diameter, diff ratio and gear ratio

when i plot hp and ft-lb on the same graph they cross at 5500rpm, so it is out a bit

i'll have some 1/4 mile times soon :D

the rpm signal is correct

edit: here's another viewpoint

rusty said:
your dyno sheet shows about 245rwhp at the point of peak torque, which is at 3918rpm (give or take a few) which is equal to 328lb/ft or 445nm at that point. thats still real wheel torque not crank torque. the only problem from there is im not too familiar with the dynologs and what results they return. i was anticipating dyno dynamics, which return around 76% of crank power as a rear wheel figure on a manual supra, but im not sure of what dynologs will do. probably closer to a dynojet?

not sure if ive shown you this before but i made a script in php to convert between the various figures, as well as show some additional units etc.

heres a link for your figures;
http://www.to4r.com/calcs/pwtq.php?power=245&rpm=3918
 
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