Dyno day for my Ex

[MikB]

You may be surprised at the numbers my Ex got with and without a Livernois 93 tune. the shop uses a Dyno Dynamics dyno. It is a 'load bearing' dyno. A load bearing dyno is as close an approximation as one can get driving on the road and therefore, the numbers seem low but, are the most accurate reading to get true numbers.

To start with, a base pull was made in stock tune, The numbers were: 196.2 whp and 170 wtq. Adding the Livernois 93 tune, the numbers were: 205.5 whp and 200 wtq.

The Livernois numbers will increase in time because of the 'learning curve' incorporated in the ECU.

All pulls were done in 4th gear.

A WOT run was done running through the gears from 1st to 4th which produced a sustained hp well above the hp seen in the normal 'tuned' pull with a max hp of 228. This is something most people don't do when they get a pull done or, at least, it is never mentioned by anyone I've noticed.

Normally, parasitic loss is measured at 15% for a manual tranny and 18% for an automatic. These numbers are based on RWD vehicles where the rotating mass is in a straight line. This is not so for FWD vehicles with cross mounted engines.

One thing that really stands out is how much parasitic loss of power is consumed in the drive train. Because the drivetrain configuration is FWD, the rotating mass has many 'corners' to overcome and that adds to power loss. In the case of my Ex, the parasitic loss is 32%. This is figured from using the advertised hp of 290 for the resulting whp of 196 produced in the dyno run today for the stock figures. The percentage ratio of torque loss will be a bit less and I haven't done the number to find out what the percentage of that would be as of yet.

By the way, I plan on talking to Livernois about a possible improvement in torque between the 2500 and 4000 rpm range as it seems torque lags a bit in that area.

In a month or so, I plan on going back in for another pull to see how much the numbers improve with the tune. For now, I'll put up the sheets and a few pics for you amusement.

 

[MikB]

I've been in contact with Livernois as they had some concern about some of what I posted and so, I made some corrections to it. However, I also should explain and this is a conclusion that seems to work for the numbers that were seen. It would appear that with the traction control off (yet to really be determined but, makes sense to me, anyway), power is distributed to all four wheels and thus, a significant increase in parasitic loss of power. So, it seems that if you do a pull with an Ex with 4WD/AWD and turn the traction control off, power is distributed evenly to all four. Having been next to the Ex when the pulls were done and seeing all four wheels spinning, I have to come to the conclusion that this is the case. Therefore, the numbers are going to come out much less than what you would expect. In my book, this is not a bad thing. Just adds new condition to the process I think. So, here's what it does when all four wheels are involved.

 

[raceuv]

and i thought mustang dynos read low....

 

[MiWiAu]

MikB, out of curiosity which terrain management mode did you have selected?

I found this explanation of the Terrain Management System, which makes me wonder if the "Sand" mode would produce maximum output for a dyno run (or perhaps the parasitic loss you indicated would negate this):

When dialed into the “Normal” setting, the TMS biases torque to the front wheels and shifts more torque to the rear only as needed. “It’s the most economical yet still allows 4WD function for optimal driving conditions,” says Scott Greca, a Ford all-wheel drive engineer who has been deeply involved in the continued development of the TMS. It gets more interesting, he points out, when conditions get more extreme. For instance, in the “Grass, gravel and snow” mode, where there is firm underlying terrain but the surface is slippery, more torque is transferred to the rear wheels, the transmission automatically upshifts into a higher gear, and the engine slightly reduces its torque output at the current throttle condition; all this prevents the wheels from spinning and with electronic stability control assistance keeps the vehicle going where the driver steers it. In “Mud/Ruts” mode, the system makes the throttle more aggressive and desensitizes stability control so the tires can spin as needed. The TMS’s toughest assignment is deep sand. In these conditions, the system automatically switches off traction control and is designed to deliver maximum torque to the wheels while keeping the transmission in low to power aggressively out of trouble.​

 

[MikB]

First, you have to understand that my numbers can not reflect those that you see from what Livernois got in their test as they used a FWD only Ex as confirmed to me by one of the guys I have been in contact with in a private discussion. Secondly, the test was done with the terrain management in 'normal' mode and with the traction control off. As the test was being done, all four wheels were putting power done to the rollers and thus the power dispersion appears to be equal to all four. In this mode, their is going to be a lot of parasitic drain on the hp and torque. The fact that the Ex is basically a FWD with a cross mounted engine adds a large loss of power itself because it's not dealing with a straight line of rotational mass. You've got a 90 degree bend to begin with in the direction of the mass and that cuts into the power output to the ground. When you add all the other components into the equation, you get a lot of power loss. In this case it is right at 32%. Geez, I think I'm repeating myself.

Anyway, for those that are more interested in getting big numbers displayed, that's possible I suppose but, I'm looking for real numbers that are reflected in actual driving and the type of dyno used does this therefore, the mediocre looking numbers. Do not despair though, with the same tune and the same setup as mine, you too, can get the same numbers. These are just the numbers you get with an AWD/4WD Ex with a 3.5L N/A.

Oh, one other thing and I think I may have mentioned this already, the numbers should improve after the 'learning' phase so, in about a month or so, I'll take it back in and see what happens and also see what happens in the different terrain modes and with the traction control still on.

 

[MiWiAu]

Right on. I was just curious. I'll be putting mine on the dyno in a few weeks. I suppose consistent settings is most important. I just wasn't sure if one mode provided a more consistent output for full power runs than another.

 

[raceuv]

Now you mention it was n/a? Makes more sense now. Carry on.

 

[MikB]

Now you mention it was n/a? Makes more sense now. Carry on.

Well, I'm glad we got that straightened out. It's not as if there is a forum here exclusively for the N/A so, it has to be put in the 'Sport' forum. If those number were from a Sport, I'd sue Ford. Have you had your Sport dynoed? It'd be interesting to see the comparison under similar circumstances. I'm actually quite pleased with the performance upgrade from the 93 tune on my Ex. The throttle response and drivability are markedly better than the stock tune. Not, of course, the kind of numbers I could get from my Mustangs but then, it is an Explorer.

 

[raceuv]

Yes the power increase that you have gained from a tune is great. I have located an awd dyno but haven't had the time to start tuning my sport with hptuners.

 

[MikB]

Seems my contact has been broken off with Livernois. Perhaps I asked a question that they are unable to answer or don't want to pursue. Maybe they are hard a work putting together the answer by doing some more tests that I suggested to provide more info on the performance of the Ex AWD configuration. I would hate to think that the only info for this configuration is mine.