First of all, yes I have no life. No need for anyone to remind me

I was kinda curious what the effective torque, hp, etc of the 6MT TSX was at various speeds.

I ended up plotting a bunch of graphs, like engine torque vs speed, hp vs speed, and torque to the wheels vs speed. Some of the data of course had to come from eyeballing a dyno, so its not exactly accurate. The other data came from various formulas.

Origionally, I wanted to plot this data against a bmw 325 and Mazda 6, to maybe give a very practical view of how these cars compare on the road. But I quickly realized this would be too hard, since I dont have enough data on those cars (most importantly an accurate dyno, and an accurate tire circumfrance measurement).

Anyways, even though my origional plan didnt work out, I thought I would share one of the graphs anyways. Torque to the wheels vs speed (by torque to the wheels, i mean the actually torque coming out of the tranny after the effects of gear ratios)

EDIT: OK I just realized that stupid website wont let me link to it.

http://www.freewebs.com/fdl/torque.htm

 

What are your units of torque? I assume there's no data < 10 mph, in which case you should start the graph at the high point. It does look a little strange that the highest torque is at the slowest speed, while the published torque peak is at ~ 4000 rpm. Assuming you start at 1st gear, 0 mph, the torque should ramp up unitl 4k rpm, down again and blip as the gears are shifted.

The shape of the curve will also vary depending on the shift strategy used. For max torque, would you shift at redline? If memory serves, a redline shift in most gears puts you at ~5k rpm in the next gear, which is already beyond the torque peak.

 

Unit of torque is pound feet of torque, but keep in mind its out of the tranny so its multiplied by gearing. The point is to show the actual rate of acceleration of the car, which decreases as you go faster.

There is no data < 15 mph because there is no data below 2500 rpms on the dyno. According to the dynos we've seen we hit peak torque at 2500 rpms, and stay flat untill about 5000. SO once you hit about 15 miles per hour, your rate of acceleration is at its peak, and then at about 25 mph is starts to drop, and its all downhill from there. I have assumed shifts as high as fuel cutoff when possible (keep in mind I am limited to using 5 mph intervals).

As far as shifting at peak torque, I think you are confusing engine torque with actual torque to the wheels, which is a factor of engine torque and gearing. (For a plotting of ENGINE torque and HP to speed see http://www.freewebs.com/fdl/enginetorquehp.htm)

You want to stay in each gear as long as possible, because even though engine torque may not be at peak, torque to the wheels is still optimal because your gear ratio is high. When you switch gears, you may put your engine in a position to make more torque, but your new gear ratio will actually reduce your rate of acceleration (torque to the wheels).


As the graph shows, the faster you go, the slower you accelerate. Which is interesting. But again, my origional plan was to plot this info against other cars to relly show the difference. Maybe i'll still do this if i have enough data.

 

Good summary! Makes sense.

 

I just let cartest map out the drive power in each gear for me given the stock tsx dyno from vtec.net

 

Ya well, not all of us are priveledged enough to have access to such a program Where can I get a copy?? (hint , hint)

 

Tinky, the y-axis says 'lb*10^1' for the units. This would mean that the peak force (in 1st) is like 23 lbs? That can't be right.

 

SO Tinky, are you going to hook me up or what. Using excel to do this stuff is a pain in the ass.

 

haha, just checked in on this thread...PM me.

TSX Hokie : remember to multipl by the units on the axis, drive power in first gear is over 2300lb ft to the ground.