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2020 stock Widebody Dyno conclusion. Went to see how accurate our performance page was while stock vs a dyno jet. From what I gather I think the page is more accurate than I would of guessed. To many variables to duplicate an exact test ,but I did try. That said the tests were not at the same location or same day. The cars performance max readings were WHP 698 & TQ 636 in I think 5 gear on my performance page. Hard to get a good grasp of the gear because I’m actually driving and the page is very delayed. The Dyno jet was WHP 683.35 & TQ 637.36 in 6th gear. I got as much data as I could with a locked ECU. The car readings DA on the day, location and time was 202.420. Same thing ,but at the dyno shop DA was 223.607. Put the gauge readings up to get what I could right before the dyno pull. The gauges picture was right before the first hit. Not sure what all this data really means and was looking for insight. Cars performance dyno %s were done at 85ft and the dyno jet was at 171ft. I also should of added the IC temp ,but didn’t even think about it. I only had a 30 minute cool down from a 2hr drive. Plus I couldn’t figure out the after run cool down feature. So I guess the verdict can still go either way to the smallest detail ,but I wanted to answer the question of cars dyno vs dynojet I had.......which I never really did ,but it was fun. Lol car was in track mode and I pulled both listed BAS fuses. I asked the dyno tech to turn off the traction control completely ,but I doubt he did. They were kind of rushing me. All 3 hits on the dyno were 2 minutes apart. Lol is that normal?
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Those baseline dyno results look really good to me. Others may want to chime in on that too.

Applying a little math...707 rated HP - 683 dyno HP = 24 HP loss. 24 HP loss / 707 HP rated is 3% loss - which seems almost TOO good. (I'm assuming your car is a standard Hellcat, not a Redeye. I'm guessing from the engine bay pic.)

Your IAT looks slightly high but not way out of line. The after run cooler would have helped but it's not a disaster if you didn't get to run it.

Most importantly - especially if this is your first dyno experience - know that a dyno is just a tuning too. They are most useful for A vs B comparisons...."A" being what you have now and "B" being whatever changes you have in mind!
 

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Those are Really good numbers, but it is a Dynojet, which more often than not, usually reads a bit high.

BigDaddyEureka is right though in that a dyno is just a tool for tuning (and bench racing) and that you have a baseline now if you decide to mod your Kitty Cat!

Congratulations on those numbers too!

By the way, that's a Great looking dyno setup with that sitting area and the display and glass wall that lets you watch things happen!
 

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2020 stock Widebody Dyno conclusion. Went to see how accurate our performance page was while stock vs a dyno jet. From what I gather I think the page is more accurate than I would of guessed. To many variables to duplicate an exact test ,but I did try. That said the tests were not at the same location or same day. The cars performance max readings were WHP 698 & TQ 636 in I think 5 gear on my performance page. Hard to get a good grasp of the gear because I’m actually driving and the page is very delayed. The Dyno jet was WHP 683.35 & TQ 637.36 in 6th gear. I got as much data as I could with a locked ECU. The car readings DA on the day, location and time was 202.420. Same thing ,but at the dyno shop DA was 223.607. Put the gauge readings up to get what I could right before the dyno pull. The gauges picture was right before the first hit. Not sure what all this data really means and was looking for insight. Cars performance dyno %s were done at 85ft and the dyno jet was at 171ft. I also should of added the IC temp ,but didn’t even think about it. I only had a 30 minute cool down from a 2hr drive. Plus I couldn’t figure out the after run cool down feature. So I guess the verdict can still go either way to the smallest detail ,but I wanted to answer the question of cars dyno vs dynojet I had.......which I never really did ,but it was fun. Lol car was in track mode and I pulled both listed BAS fuses. I asked the dyno tech to turn off the traction control completely ,but I doubt he did. They were kind of rushing me. All 3 hits on the dyno were 2 minutes apart. Lol is that normal? View attachment 563543 View attachment 563544 View attachment 563545 View attachment 563546 View attachment 563548 View attachment 563549
I have questions. A. Is it a 717 HP Hellcat not Redeye and A8 trans? And how many miles on her at the time of Dyno. Why did they use 6th gear on the Dyno Pull?
 

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Numbers seem too high if not a Redeye. STD correction factor is inflating it 3% also. Is the car an M6? If not, that dyno needs calibration.
 
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Discussion Starter #6
I have questions. A. Is it a 717 HP Hellcat not Redeye and A8 trans? And how many miles on her at the time of Dyno. Why did they use 6th gear on the Dyno Pull?
Non redeye hellcat with an A8. 5400 miles on the car. From what I was told it’s best to get as close as you can to a 1 to 1 ratio. I’ve heard it’s more accurate. Not really sure. I have a 3.09 differential so I figured my top end wouldn’t over run in 6th. My MPH on the car after the run was 167. My cars gauge on the dyno performance page as well as 13PSI. Had me scratching my head. It’s very hard to validate it with a delayed page reaction #s. I put a picture up.
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Sounds like a very optimistic dyno. No big deal, some dyno's read higher than others. STD correction factor also adds 3%.
 

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Discussion Starter #8
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Those baseline dyno results look really good to me. Others may want to chime in on that too.

Applying a little math...707 rated HP - 683 dyno HP = 24 HP loss. 24 HP loss / 707 HP rated is 3% loss - which seems almost TOO good. (I'm assuming your car is a standard Hellcat, not a Redeye. I'm guessing from the engine bay pic.)

Your IAT looks slightly high but not way out of line. The after run cooler would have helped but it's not a disaster if you didn't get to run it.

Most importantly - especially if this is your first dyno experience - know that a dyno is just a tuning too. They are most useful for A vs B comparisons...."A" being what you have now and "B" being whatever changes you have in mind!
Thank you. Yes the it’s a non redeye with an A8. I was told the 19-20 models are rated at 717 ,but I’m really starting to think these cars are under rated. Most of all yes just a tuning tool. I’m curious how much my altitude play a factor. Now I know I was only 171ft of elevation and that’s nothing big ,but none the less curious. This is my first ever tuning tool. In your experience did you pull two fuses or just one? I saw my fuse box had two listed as a ABS fuse.
 

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Numbers seem too high if not a Redeye. STD correction factor is inflating it 3% also. Is the car an M6? If not, that dyno needs calibration.
Regular A8 hellcat non redeye. Yeah I asked the facility what was the highest stock reading and he said 620-640. Which makes me wonder my 13PSI again. At the end of the day I gotta go to the track and see where the car is really at.
 

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View attachment 563553

Thank you. Yes the it’s a non redeye with an A8. I was told the 19-20 models are rated at 717 ,but I’m really starting to think these cars are under rated. Most of all yes just a tuning tool. I’m curious how much my altitude play a factor. Now I know I was only 171ft of elevation and that’s nothing big ,but none the less curious. This is my first ever tuning tool. In your experience did you pull two fuses or just one? I saw my fuse box had two listed as a ABS fuse.
You pulled the correct fuse
 

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Sounds like a very optimistic dyno. No big deal, some dyno's read higher than others. STD correction factor also adds 3%.
The difference in NOT a set 3%, it depends on atmospheric conditions. See pictures below of the same dyno run with a few different correction factors used

I’ve been wondering the difference between SAE and STD!

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thanks for clarification and if your the same go man go on YouTube I follow you! Lol
If that is Speedy no not the same person but I follow Speedy as well. He has some very informative content for sure.
On the subject of dyno readings what’s best for real numbers at the time of the pull is UNCORRECTED numbers as they use the actual atmospheric conditions at the time of the pull.
 

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Regular A8 hellcat non redeye. Yeah I asked the facility what was the highest stock reading and he said 620-640. Which makes me wonder my 13PSI again. At the end of the day I gotta go to the track and see where the car is really at.
Yea, a typical A8 is between 620-640 SAE. Did you buy the car new? An Incognito pulley would put the car around 13psi and still look stock but if you bought it new then its got to be stock.
 

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I purchased it new off the showroom. The only things I did was LMI, DIRS brace, nitto 555r2s at 32psi approximate at the time of the tests. Now what I found to be interesting was the formula for SAE correction. I did the math uncorrected to SAE and saw a big difference. HP 652.59 TQ 610.69. With a leg maker stock tune I think that’s more realistic.
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The cognitive dissonance is strong in here.

This isn't a pre-18 HC, it is a 19+. Anything related to early model dyno sessions does not necessarily apply here. Lots of factors changed to make this '20 the strong runner it appears to be. Dynojet or not.


You are looking at an SAE 745hp car, gents. Redo your math.
 

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Seems like a very, very happy dyno. Doesn’t matter since it’s a baseline and a tuning tool. I run on a mustang heartbreaker that reads 18% lower than the “average” dynojet.

Doesn’t lower my trap speed or make my car any faster.

Trap speed is the true show of hp. What kind of traps are you running ?
 

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It's widely known to be between 2 and 3%.
I can agree here on the 2-3% part, was just trying to say it’s not multiplier that’s the difference from all these ratings, my apologies for coming off harsh. Look at DIN, the German standard, it’s about the furthest from SAE in terms of rating more then non corrected numbers go. A dyno is a good tool to use for seeing if changes make a positive or negative impact on power especially if one uses the same dyno and under similar atmospheric conditions. Some say track times are best which may be so with a automatic but with a stick consistency especially at high HP levels is tough to make comparisons with except for trap speed which is a good measure of peak HP being made but again atmospheric conditions play into that as well. I know I see a 2-4 mph difference 1/4 difference from -1000 DA to +1000 DA, on the dyno no different. Plus boost on the dyno is different as well, I see 1/2-3/4 psi and 150 mg air charge difference between dyno to 4th gear with ram air effect helping boost out in real word track or street power making.
 
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