Thought of the day.

67 AGAIN said:
That’s about right.

And when you do this corrective math, the percentage to use for the correction also varies a bit depending if you start from known crank number and work down to rw number or if you start from rw number and work up to crank number.

With the Mustangs and the Tremec manual transmissions, you basically lose around 15% from crank to rw.
With automatics, it’s roughly 18%.
So if you know crank number, you figure out 15% or 18%, depending on transmission, and subtract that number from crank number to get rw number.

However, when you’re going the other way, rw number to crank, if you take rw number and multiply by 1.15 or 1.18, depending on transmission, the numbers fall short a bit.

I’ve discovered that when going from rw to crank number the corrected percentage to use to get back very close to initial crank number should be, in the case of manual- rw number X 1.18 and in the case of automatic- rw number X 1.21.

Those are the numbers I used above.
710 X 1.18 and
710 X 1.21.
Click to expand...
We’ll explained thanks
 
15% is fairly accurate for older Mustangs, but newer ones seem to lose less
from what I am seeing on dyno numbers.
As little as 8-10%
Presuming Ford is telling the truth.
they are known for under quoting HP.
 
26B30646-25C0-4D6A-966E-8EDB683C22CA.jpeg

Tomorrow it will be 58 years
 
Well, if you start from the advertised 480, pulling consistent 450-460 means they are only losing 5% in the driveline.
That would peg the rw hp at 456.

That seems very low for any driveline.
Looks like Ford is under-reporting numbers again.

They were suspected of doing that with the Voodoo engine.
All dyno tests showed more than the advertised 526.

After all, a Tremec is a Tremec.
A clutch is a clutch.
A driveshaft spinning a pinion has not changed at all.
Biggest difference is IRS versus solid axle.
I’m not an engineer, but is IRS more or less parasitic than solid axle?

The Mustang driveline has not evolved that much.
They haven’t gone to carbon fibre parts or anything that wild.

And that 15% number held true for so long. I mean generations long.
Now Ford has found a magic formula in the Mustang to reduce parasitic loss, and we have not herd about this in the news?

I don’t think so Tim!
 
I know mine dyno'ed at 484 on a wet evening,
odds are take humidity out of air, would have been 2-3 more.
Mine has carbon wheels, I am sure help. thats 8-9%
even if a bit under reported, no where near 15% loss

2014 GT 500 is about 10-11 %

Some say engineers have refined transfer of power.
To be honest, above my pay grade but I wouldn't be surprised.
Ford engineers have also improved the tunning so much
most stock setups on new cars, dyno won't gain enough from custom
tune to justify the money, where as 10-20 year cars custom tune
could get 15-25 HP just from a good tune.

TImes are a changing and I am not surprized at drop in loss.

In fairness Marc, the stock clutches are incredible, Tremec has up its game,
lots has changed in last 10 years.
 
Mine was dyno'ed with 91 as we got there late and I actually had no plan on
putting it on the dyno, Pete did it for free, he wanted to see the numbers.

I was there when he did the 14 GT 500 and told the guy, don't bother with
custom Tune, as Ford had done an amazing job tuning that car, he wouldn't
get anough to justify the money. Older cars had much more to give in tuning area.
 
Ohtobbad said:
I know mine dyno'ed at 484 on a wet evening,
odds are take humidity out of air, would have been 2-3 more.
Mine has carbon wheels, I am sure help. thats 8-9%
even if a bit under reported, no where near 15% loss

2014 GT 500 is about 10-11 %

Some say engineers have refined transfer of power.
To be honest, above my pay grade but I wouldn't be surprised.
Ford engineers have also improved the tunning so much
most stock setups on new cars, dyno won't gain enough from custom
tune to justify the money, where as 10-20 year cars custom tune
could get 15-25 HP just from a good tune.

TImes are a changing and I am not surprized at drop in loss.

In fairness Marc, the stock clutches are incredible, Tremec has up its game,
lots has changed in last 10 years.
Click to expand...

I have no doubt there are improvements.
But I still suspect under-reporting by Ford.

The 2014 Shelby you use as example, that’s an other prime candidate for under-reporting.
That 5.8 Trinity engine was a monster.
First use of Wire Arc Plasma Transfer technology that is now in the 3rd gen Coyote, Voodoo and Predator engines.
It had extra cooling viens in the block compared to the 5.4 from which it was derived.
It was purpose built for forced induction power.
That one had to have been under-reported.

The numbers you are posting represent a 30 to 40% improvement in loss reduction
That’s huge.
Any company the size of Ford would brag about that in their advertising.
It would work its way into the news.

Especially now, with price of gas and push for electrification, zero emissions and efficiency.
A car maker would spin that to say that their flagship car is now 30 to 40% more efficient than before.
Less loss like that should improve fuel consumption numbers.

The under-reporting ties in with the EPA putting the squeeze on that caused Ford to reduce Coyote reported numbers for 2022.

Interestingly enough, GM was able to conform to the new EPA standards without reducing power in the Corvette.

Yes, your carbon wheels do contribute to narrowing the gap because they are easier to spin.

Totally agree with you on the efficiency of engines now compared to before, and the efficiency of tunes.

The efficiency of an engine has no bearing on the parasitic loss in the driveline that comes behind it.

And yes, the Ford factory clutches are great clutches.

I feel we could use input from our resident engineer and master mechanic/teacher, Martin and Gerry on this.

Cherrs. ??
 
Ohtobbad said:
Mine was dyno'ed with 91 as we got there late and I actually had no plan on
putting it on the dyno, Pete did it for free, he wanted to see the numbers.

I was there when he did the 14 GT 500 and told the guy, don't bother with
custom Tune, as Ford had done an amazing job tuning that car, he wouldn't
get anough to justify the money. Older cars had much more to give in tuning area.
Click to expand...

No doubt older cars benefited from tune more than new cars.

Your car would have been a bit closer on 93 octane, further reducing gap between advertised crank number and rw number.
To me, that’s further evidence your car’s numbers are under-reported.

It’s not a secret.
Many tests from Car and Driver, Road & Track, Hot Rod magazines have all found the Voodoo puts down more than Ford advertised.
Their conclusions are not that the driveline is that much more efficient.
They attribute to Ford under-reporting.
 
67 AGAIN said:
Well, if you start from the advertised 480, pulling consistent 450-460 means they are only losing 5% in the driveline.
That would peg the rw hp at 456.

That seems very low for any driveline.
Looks like Ford is under-reporting numbers again.

They were suspected of doing that with the Voodoo engine.
All dyno tests showed more than the advertised 526.

After all, a Tremec is a Tremec.
A clutch is a clutch.
A driveshaft spinning a pinion has not changed at all.
Biggest difference is IRS versus solid axle.
I’m not an engineer, but is IRS more or less parasitic than solid axle?

The Mustang driveline has not evolved that much.
They haven’t gone to carbon fibre parts or anything that wild.

And that 15% number held true for so long. I mean generations long.
Now Ford has found a magic formula in the Mustang to reduce parasitic loss, and we have not herd about this in the news?

I don’t think so Tim!
Click to expand...
Again 450/460hp like you said only 5% seems low, just because it’s on the internet doesn’t make it true. Everything can be manipulated
 
67 AGAIN said:
I have no doubt there are improvements.
But I still suspect under-reporting by Ford.

The 2014 Shelby you use as example, that’s an other prime candidate for under-reporting.
That 5.8 Trinity engine was a monster.
First use of Wire Arc Plasma Transfer technology that is now in the 3rd gen Coyote, Voodoo and Predator engines.
It had extra cooling viens in the block compared to the 5.4 from which it was derived.
It was purpose built for forced induction power.
That one had to have been under-reported.

The numbers you are posting represent a 30 to 40% improvement in loss reduction
That’s huge.
Any company the size of Ford would brag about that in their advertising.
It would work its way into the news.

Especially now, with price of gas and push for electrification, zero emissions and efficiency.
A car maker would spin that to say that their flagship car is now 30 to 40% more efficient than before.
Less loss like that should improve fuel consumption numbers.

The under-reporting ties in with the EPA putting the squeeze on that caused Ford to reduce Coyote reported numbers for 2022.

Interestingly enough, GM was able to conform to the new EPA standards without reducing power in the Corvette.

Yes, your carbon wheels do contribute to narrowing the gap because they are easier to spin.

Totally agree with you on the efficiency of engines now compared to before, and the efficiency of tunes.

The efficiency of an engine has no bearing on the parasitic loss in the driveline that comes behind it.

And yes, the Ford factory clutches are great clutches.

I feel we could use input from our resident engineer and master mechanic/teacher, Martin and Gerry on this.

Cherrs. ??
Click to expand...
Yes please chime in thanks
 
The only way to get exact numbers, would be to take engine out and run it on
engine dyno, then run out on normal dyno. Also some dynos are not 100% accurate
More often than not, bad tune guys numbers are not right.

One of the reasons on this site, you only ever hear two places,
Desilvas or Petes Performance.

Also weather plays a factor, cooler weather, cars run better,
One of the reasons I likes Petes, Spring New hampshire,
is very close to Nova Scotia weather.

400 HP plus at wheels is more than average drivers can handle, as we see
by endless videoss of guys losing cars when pulling out of places.
 
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