917WHP/1108fwhp @15lbs, Smoothboost

[Torinate]

Thanks for the name change edit!

How did they calculate the crank horsepower? I’ve never seen crank listed on any dyno I’ve ever done. Is this a a new thing or dependent on the dump itself?

I understand the not wanting to thrash the car and break parts, but how do you for fact there is 19% loss?

Not knocking or doubting, just never seen that. I’d love to know my crank and slippage.

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[DougS550]

Thanks for the name change edit!

How did they calculate the crank horsepower? I’ve never seen crank listed on any dyno I’ve ever done. Is this a a new thing or dependent on the dump itself?

I understand the not wanting to thrash the car and break parts, but how do you for fact there is 19% loss?

Not knocking or doubting, just never seen that. I’d love to know my crank and slippage.

First I would like to mention, a Dyno is a tuning device to ensure your engine is Optimally Tuned and to measure performance. My car was on a AWD Mustang Dyno which the owner of the shop calls "Heartbreak Dyno" due to cars coming from other Dynos like a Dynojet to his Mustang Dyno "Always" read low.
Example: He said he had a Viper come in for some upgrades where the owner said he just had it on a Dynojet before he left Texas. He said on the Dynojet he got 1200 wheel horsepower.
When they did a baseline at his shop here in Indianapolis, the car without changing anything produced 1054 wheel horse power.
Note: My Tuner said he didn't see any transmission slippage evn with the 19% difference between CHP and WHP. But I will verify.
As far as Different types of Dynos, I don't care. I went to get it tuned so my engine doesn't grenade due to a poor tune.

Here you go on How :

https://www.google.com/search?q=is+a+mustang+Dyno+a+brake+or+Eddy+current+dyno&sca_esv=1740ddc3d2160827&sxsrf=AHTn8zq8DzzaBFj9t62t7Dxtg6-obq89iQ:1746124561400&ei=Eb8TaNGaGNiGw8cPnK6tuAU&ved=0ahUKEwiR59zx9IKNAxVYw_ACHRxXC1cQ4dUDCBI&uact=5&oq=is+a+mustang+Dyno+a+brake+or+Eddy+current+dyno&gs_lp=Egxnd3Mtd2l6LXNlcnAiLmlzIGEgbXVzdGFuZyBEeW5vIGEgYnJha2Ugb3IgRWRkeSBjdXJyZW50IGR5bm8yBRAhGKsCMgUQIRirAjIFECEYqwJItmBQAFi-XXAAeAGQAQCYAYYBoAHFIaoBBTI5LjE3uAEDyAEA-AEBmAIuoAKbI8ICBBAjGCfCAgoQIxiABBgnGIoFwgILEAAYgAQYkQIYigXCAgsQABiABBixAxiDAcICBRAuGIAEwgIOEC4YgAQYsQMY0QMYxwHCAg4QABiABBixAxiDARiKBcICChAAGIAEGEMYigXCAgsQLhiABBixAxiDAcICDhAuGIAEGLEDGIMBGIoFwgIIEAAYgAQYsQPCAgUQABiABMICChAAGIAEGBQYhwLCAggQABgWGAoYHsICBhAAGBYYHsICCxAAGIAEGIYDGIoFwgIIEAAYgAQYogTCAgUQABjvBcICBRAhGKABmAMA4gMFEgExIECSBwUyNi4yMKAH9IwCsgcFMjYuMjC4B5sj&sclient=gws-wiz-serp

 

[qwiknotch]

A wheel dyno can't 100% measure crank hp, regardless of what wheel dyno used. You have to pull the engine and use an engine dyno.

That being said, the operator can put in a numbered percentage based on all the dynos he has done with a particular combo, like in this instance, stock converter and 3.55 gears and get really close tho. If he has done 60 10r80 cars with boost and 3.55 gears and they all read within a certain percentage, then he can calculate crank hp within a very close margin.

Now If the dyno has a driveshaft collar, it can measure converter slip which is the difference between engine rpm and driveshaft rpm and gear ratio.
If you want to get crazy accurate, you can do what I did with my old race car with the clutchelss 4 speed and have engine rpm, input shaft speed sensor and driveshaft collar sensor, then you dont have to worry about gear ratio. But that is overkill, I did it to dial in the slipper clutch quicker

 

[DougS550]

A wheel dyno can't 100% measure crank hp, regardless of what wheel dyno used. You have to pull the engine and use an engine dyno.

That being said, the operator can put in a numbered percentage based on all the dynos he has done with a particular combo, like in this instance, stock converter and 3.55 gears and get really close tho. If he has done 60 10r80 cars with boost and 3.55 gears and they all read within a certain percentage, then he can calculate crank hp within a very close margin.

Now If the dyno has a driveshaft collar, it can measure converter slip which is the difference between engine rpm and driveshaft rpm and gear ratio.
If you want to get crazy accurate, you can do what I did with my old race car with the clutchelss 4 speed and have engine rpm, input shaft speed sensor and driveshaft collar sensor, then you dont have to worry about gear ratio. But that is overkill, I did it to dial in the slipper clutch quicker

True, you would have to pull to get 100%. The question asked about how does a dyno derive Crank Horse power and so I provided the request info. And of course a HUB Dyno would be even more accurate.

 

[Torinate]

Every time I’ve dynoed any car I’ve had they’ve said theirs was a heartbreak dyno.

Exactly! A dyno is just a tool!

Time for the track to see what it’s actually putting down.

Let’s see that MPH!

 

[DougS550]

Every time I’ve dynoed any car I’ve had they’ve said theirs was a heartbreak dyno.

Exactly! A dyno is just a tool!

Time for the track to see what it’s actually putting down.

Let’s see that MPH!

I plan to but I will buy a Draggy first and do 60-130 runs for that takes out most start traction issues and one can compare with other

Every time I’ve dynoed any car I’ve had they’ve said theirs was a heartbreak dyno.

Exactly! A dyno is just a tool!

Time for the track to see what it’s actually putting down.

Let’s see that MPH!

I plan on it. But even with Toyo R888R 325/30/19 tires on the track it will not see its potential. Now I do feel with a Draggy 60-130 would be a better and more accurate comparison. I think I will try both for I am interested in seeing how it tracks.
I just got the specific info I had requested from Derel Wengerd. These dynos are with my Smoothboost Controller. It is Interesting

 

[Joshinator99]

You can get a healthy idea of CHP by looking at MAF data. Every lb/min is roughly equal to 10 HP.

You can’t compare drivetrain loss vs a stock NA motor. You’re now turning a blower and at this power level it’s eating 50-60 CHP to turn at your HP peak. So your drivetrain loss will be higher than a stock engine. It’s obviously still worth the trade off.

 

[WD Pro]

Going off topic, sorry OP ...

You can get a healthy idea of CHP by looking at MAF data. Every lb/min is roughly equal to 10 HP.

What kind of typical tolerance can be applied to that ?

It's just that I have clocked just over 47 at just under 500ft, which seems high, especially considering I'm a euro spec 2020 Gen3 with only a few basic mods ... ?

WD

 

[NGOT8R]

@DougS550 I may have missed it in this thread if you mentioned it, but do you have the ability to ramp in boost with your setup? If so, that may be what’s needed to get you out of the hole without too much trouble.

 

[Joshinator99]

Going off topic, sorry OP ...



What kind of typical tolerance can be applied to that ?

It's just that I have clocked just over 47 at just under 500ft, which seems high, especially considering I'm a euro spec 2020 Gen3 with only a few basic mods ... ?

WD

The range is generally 9.5 to 10.5 HP per lb/min airflow. 47 lb/min on a Gen3 Coyote is very realistic, so that puts you in the 446-493 HP range. I’m not sure what you’ve got for mods but if you’re mostly stock then the lower end of that scale is probably close. It’s great for estimating but not something I’d generally use for HP bragging rights. Timeslip MPH is best for that. ;)

 

[DougS550]

@DougS550 I may have missed it in this thread if you mentioned it, but do you have the ability to ramp in boost with your setup? If so, that may be what’s needed to get you out of the hole without too much trouble.

You know what, we made no changed to the tune from max to minimum and wengerd said the parameters looked good. So, I see no reason why I coulsnt have the boost knob accessible during launch, and set boost to minimum during launch, (which is around 660 hp) then start to dial up after 100'. The cars ECM can definitely adjust accordingly.

 

[robvas]

Going off topic, sorry OP ...



What kind of typical tolerance can be applied to that ?

It's just that I have clocked just over 47 at just under 500ft, which seems high, especially considering I'm a euro spec 2020 Gen3 with only a few basic mods ... ?

WD

It might not matter too much but from what i understand you also need to factor your fuel trims into that calc

 

[WD Pro]

The range is generally 9.5 to 10.5 HP per lb/min airflow. 47 lb/min on a Gen3 Coyote is very realistic, so that puts you in the 446-493 HP range. I’m not sure what you’ve got for mods but if you’re mostly stock then the lower end of that scale is probably close. It’s great for estimating but not something I’d generally use for HP bragging rights. Timeslip MPH is best for that. ;)

I'm not a USDM car though

I'm a RHD euro which means I have Cats, GPF's, and a crappy exhaust manifold due the RHD steering shaft. We are officially rated at 449 PS (crank) which is 443 HP.

Only mods are a AEM dry filter, no carbon trap, a big mouth (on the car ... lol), and a H pipe. We all get active exhaust over here as standard, and it's always in track.

It might not matter too much but from what i understand you also need to factor your fuel trims into that calc

I need to do a bit more messing around / testing, and increase my knowledge (and let it run to redline)

WD

 

[NGOT8R]

You know what, we made no changed to the tune from max to minimum and wengerd said the parameters looked good. So, I see no reason why I coulsnt have the boost knob accessible during launch, and set boost to minimum during launch, (which is around 660 hp) then start to dial up after 100'. The cars ECM can definitely adjust accordingly.

This may even be stretching a bit, but is setting the boost knob to minimum and adding a scramble button (like on a turbo car) on the steering wheel to give you max boost once you’ve gotten out of the hole and hooked up an option for you? This way you wouldn’t have to reach over to the glove compartment to turn the boost knob to full boost while on a pass and can keep your attention fully focused on driving the car.

 

[DougS550]

This may even be stretching a bit, but is setting the boost knob to minimum and adding a scramble button (like on a turbo car) on the steering wheel to give you max boost once you’ve gotten out of the hole and hooked up an option for you? This way you wouldn’t have to reach over to the glove compartment to turn the boost knob to full boost while on a pass and can keep your attention fully focused on driving the car.

That's what I was thinking. I just need to verify if the rheostat adjust OHMs or voltage which it sends to controller to adjust the electric boost valve. I was thinking about using a adjustable relay/delay box so I could set the delay on boost increase.

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