Firepunk UCC Pro Street Build

fatty said:
Was it corrected?
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From a couple of other dyno sheets I saw posted it looked as if they were using a .99 correction. I'm not a dyno expert by any means but think that 1.00 is uncorrected, so I would say it was basically uncorrected.
 
LAmiller said:
It was pretty much at sea level, so correction wasn't a factor, the RPM was calibrated off roller speed and the dyno sheet shows I lifted at 3400rpm and my data log shows I lifted at 3900rpm, so I was either spinning or the rpm was off, affecting the TQ number. Regardless, it doesn't change the HP but would be closer to 3500ft lbs accurading to the data log. I ran a tune that did around 2000hp on the engine dyno and hit it with two big nitrous solenoids on the dyno, so I think the hp is accurate. We were still running a tune that did 1472hp on the engine dyno for the drag strip and ran consistent 5.40s all day.
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If the RPM's were off, all the numbers are bad

HP = (RPM * Torque)/ 5252

Regardless of that, you've already proven what you have and are good enough to come tell everyone there was an issue. Some others would be running around bragging over the numbers even when they know they were wrong. It's refreshing to see you only want the truth be told about your truck. Others could sure learn from your actions
 
It was a dynocom, and actually that dyno calculates tq/hp backward. It uses the roll torque to calculate the hp and then back calculates the tq according to the engine rpm calculations based off of roll speed when using snapshot. The HP will remain accurate even if the rpm was totally lost, but the torque would be off. If you do not use any kind of engine RPM recording (snap shot or optical) you will still get accurate HP but no engine torque readings.
 
phale said:
It was a dynocom, and actually that dyno calculates tq/hp backward. It uses the roll torque to calculate the hp and then back calculates the tq according to the engine rpm calculations based off of roll speed when using snapshot. The HP will remain accurate even if the rpm was totally lost, but the torque would be off. If you do not use any kind of engine RPM recording (snap shot or optical) you will still get accurate HP but no engine torque readings.
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If the Dynocom has a Torque cell to measure real torque at the roller it will still read wrong HP and torque, if the tires are slipping as the numbers it assumes to get back to engine RPM would still be wrong. Since Lavon said he backed off at 3900 by the logger, yet the dyno sheet showed, 3400 something was amiss.

His truck is great and he has proven that well already.
 
phale said:
It was a dynocom, and actually that dyno calculates tq/hp backward. It uses the roll torque to calculate the hp and then back calculates the tq according to the engine rpm calculations based off of roll speed when using snapshot. The HP will remain accurate even if the rpm was totally lost, but the torque would be off. If you do not use any kind of engine RPM recording (snap shot or optical) you will still get accurate HP but no engine torque readings.
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That's interesting. I didn't know anyone did it that way. How does it calculate it? Roller rpm, and liquid cooled electric motor putting in a calibrated load?

:Cheer:
 
Eddy current. 2 dissimilar metals (aluminum and steel) Rhone is fixed, current is applied to the other like an electromagnet, and it resists rotating force. Mdore current =more load. Of you know how much current it takes to control a certain rpm, you can calculate tprque and hp.
 
On our shop's Mustang dyno, HP is measured from the roller acceleration rate, and TQ is calcuated based on engine speed which is synced with roller speed. It's impossible to trick the HP output with tire slippage and make it throw unrealistic raw HP figures, but it will throw unrealistic TQ numbers if there is slippage. For example, if everything was synced up correctly and then we made a pull with the torque converter unlocked, HP would drop some because of fluid coupling losses in the converter, but the engine torque numbers would increase a little because the unlocked converter might let the engine rev to 3000 rpm and make peak HP when the roller speed is less where it computes 2000 rpm engine speed and 1000 HP at 2000 RPM is 2626 TQ and the same truck with the converter locked might make 1200 HP at 3000 RPM which is 2100 TQ and exactly what the dyno would display with the converter locked.

Shift spikes on the dyno are actually real horsepower, it's just not 100% instantaneous engine output derived HP, it's a combination of engine HP, plus converted rotational inertia (HP made earlier in the run and stored as engine/flywheel/converter momentum and then released to the rollers when the tranny shifts and drops rotational speed/momentum of the engine.
 
Big Blue24 said:
On our shop's Mustang dyno, HP is measured from the roller acceleration rate, and TQ is calcuated based on engine speed which is synced with roller speed. It's impossible to trick the HP output with tire slippage and make it throw unrealistic raw HP figures, but it will throw unrealistic TQ numbers if there is slippage. For example, if everything was synced up correctly and then we made a pull with the torque converter unlocked, HP would drop some because of fluid coupling losses in the converter, but the engine torque numbers would increase a little because the unlocked converter might let the engine rev to 3000 rpm and make peak HP when the roller speed is less where it computes 2000 rpm engine speed and 1000 HP at 2000 RPM is 2626 TQ and the same truck with the converter locked might make 1200 HP at 3000 RPM which is 2100 TQ and exactly what the dyno would display with the converter locked.

Shift spikes on the dyno are actually real horsepower, it's just not 100% instantaneous engine output derived HP, it's a combination of engine HP, plus converted rotational inertia (HP made earlier in the run and stored as engine/flywheel/converter momentum and then released to the rollers when the tranny shifts and drops rotational speed/momentum of the engine.
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That makes sense. Any idea why it's done this way? It's definitely easier to measure a load cell and rpm than acceleration. Or is this just because folks tend to be more interested in HP instead of TQ?
 
Dyno racing... just a number. I find it interesting how I can run 5.40s @ 135-137 all day on a 1472hp fuel only tune and the response is overwhelming, everyone loves it. Get on the dyno, put it on kill mode with nitrous, put up a 2348HP number, and it starts arguments everywhere. At this level, a chassis dyno is NOT the best option for finding peak power, If you have a 1600+hp capable setup, it belongs on the engine dyno if you really want bragging rights.

We hope to learn power management at the track this summer and be able to utilize a little more of the power we have on tap, and let the time slip advertise our usable horsepower.

Lavon
 
So many of my questions about the dynocom answered here.
35834948f81785d567a5ec0a3351df9a.jpg


The last pull where my torque moved 300rpm made no sense to me.


Sent from my XT1053 using Tapatalk
 
LAmiller said:
Dyno racing... just a number. I find it interesting how I can run 5.40s @ 135-137 all day on a 1472hp fuel only tune and the response is overwhelming, everyone loves it. Get on the dyno, put it on kill mode with nitrous, put up a 2348HP number, and it starts arguments everywhere. At this level, a chassis dyno is NOT the best option for finding peak power, If you have a 1600+hp capable setup, it belongs on the engine dyno if you really want bragging rights.

We hope to learn power management at the track this summer and be able to utilize a little more of the power we have on tap, and let the time slip advertise our usable horsepower.

Lavon
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And that how it should be done. Time slips showing what you can do. Not some Dyno number that proves nothing.

Also it was awesome to see the truck in person this weekend.

Patrick.
 
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LAmiller said:
Dyno racing... just a number. I find it interesting how I can run 5.40s @ 135-137 all day on a 1472hp fuel only tune and the response is overwhelming, everyone loves it. Get on the dyno, put it on kill mode with nitrous, put up a 2348HP number, and it starts arguments everywhere. At this level, a chassis dyno is NOT the best option for finding peak power, If you have a 1600+hp capable setup, it belongs on the engine dyno if you really want bragging rights.

We hope to learn power management at the track this summer and be able to utilize a little more of the power we have on tap, and let the time slip advertise our usable horsepower.

Lavon
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would you please stop making sense?

Thanks,
the Management
 
LAmiller said:
Dyno racing... just a number. I find it interesting how I can run 5.40s @ 135-137 all day on a 1472hp fuel only tune and the response is overwhelming, everyone loves it. Get on the dyno, put it on kill mode with nitrous, put up a 2348HP number, and it starts arguments everywhere. At this level, a chassis dyno is NOT the best option for finding peak power, If you have a 1600+hp capable setup, it belongs on the engine dyno if you really want bragging rights.

We hope to learn power management at the track this summer and be able to utilize a little more of the power we have on tap, and let the time slip advertise our usable horsepower.

Lavon
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:clap::clap::clap::clap::clap:
 
I saw a pic of the trans out at the race. I'm curious as to what was the issue? Also, do you run a bolted in sprag in your trans or any of the stages you sell?
 
kleann said:
I saw a pic of the trans out at the race. I'm curious as to what was the issue? Also, do you run a bolted in sprag in your trans or any of the stages you sell?
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I was talking to Larson and he said something did not get torqued down when the transmission was freshened up. So that is why it was out.
 
We pulled it the day before in a hurry to make sure it didn't hurt the directs when we blew the transmission line during the sled pull in Utah, everything was perfect so we put it together and unfortunately the pump stator support bolts got missed and after a trip to tech we lost all line pressure so we dropped transmission, torqued the stator support bolts and went racing, good thing it showed up before the first pass! The joys of human error :)
 
It was impressive watching you guys all work on that issue, extremely fast with little communication between each other!
 
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