[2018HellKitty]

So I did a base pull just to see where I’m at before making any additional mods and on a dynojet and it was 572. Mods are mid muffler and rear muffler/resonator delete and Legmaker intake. That’s it. I did fill up with 91 instead of 93 because 93 is a little harder to find here but these numbers seem low to me.
Maybe the Legmaker being wide open sucking in hot air? Also the outside temp was 93 degrees. He said the intake temps were around 140 - 150 during the pulls.

 

[beep-beep-vroom]

What exactly were you expecting? I'm very cynical about bolt-on stuff...always over promise, and under deliver. Isn't you car a 707 horsepower? 572 at the wheels seems like very typical 20% parasitic loss.

 

[baabootoo]

Go to a drag strip and see what your trap speed is. That is the real answer. SC temp? Verify the gas rating or just pump stuff?

 

[fumanchu182]

At those temperatures timing is being pulled. You are not getting an accurate reading, I'm surprised the dyno didn't have a big ass fan in front of the car to keep air moving.

 

[2018HellKitty]

Haven’t taken it to the strip yet, just was trying to see where I was currently for comparison. I know that’s where it matters but I’m just collecting some preliminary data. 707 with the 20% loss is right near the money at 572 but maybe others can chime in on stock hellcats on a dyno.. I heard that 707 was a very underrated # and averages are near the 610-630 rwhp numbers. Is this not accurate? The dyno did have a fan, but I wouldn’t classify it as a “big ass” fan. Medium size squirrel cage type blowing right into the grill from around 5’ away

 

[Vet Rider]

Did you have the cat recall done?

 

[2018HellKitty]

😳 what recall. I bought it with 5000 miles and last I checked it said no available recalls… Which one are you referring to?

 

[Vet Rider]

😳 what recall. I bought it with 5000 miles and last I checked it said no available recalls… Which one are you referring to?

If it had been done since you are saying there are no recalls for your car, than thats probably your problem. The cat recall for hellcats swapped out the cats for newer cats and o2's and also reflashed your car with a much higher version of their cat over temp protection. I was seeing the same ## as you with my 21 on the dyno when it was heat soaked and the cat over temp was kicking in. I picked up 100hp letting it cool. Then with a tune only on 93, with COT turned off I picked up another 70 or so hp. Car dynoed 553 with COT kicking in, 655 cold with no cot then 734 with tune only no COT all on 93. These cars are very badly gimped with that new calibration if you still have it once they get hot.

I'd call a tuner and get a tune. You are out of warranty now so YOLO and enjoy that close to 200hp you should gain.

 

[2018HellKitty]

Wow! Good info. Appreciate that! I’m about to order an unlocked pcm to get tuned so I’ll definitely start there

 

[Vet Rider]

In case you don’t believe me. Both dyno sheets. The cold stock and hot tuned. Same dyno. 21 stock charger HC non redeye

 

[2018HellKitty]

That’s nuts! Did that recall apply to one as old as mine? Yours is a bit newer

 

[Vet Rider]

My car hitting cat over temp and falling on its face. If you listen, you can hear it pull back at the near end of the run.

And then after tune when it was straight ripping. No issues.

And trans run through on the dyno.

 

[Vet Rider]

That’s nuts! Did that recall apply to one as old as mine? Yours is a bit newer

Yeah I believe it was for all hellcats all the way back to 2015.

 

[2018HellKitty]

Definitely checking up on this for mine. Very pretty car by the way. Love the wide body on chargers

 

[Vet Rider]

Definitely checking up on this for mine. Very pretty car by the way. Love the wide body on chargers

Lol it was nice. Sold it and made $25k profit. Bought another ZL1 and honestly couldnt be happier. No more hellcat weirdness. The ZL1 just rips. Its going in for LT Headers, lower pulley, ECM/TCM tune and rotofab CAI. Should make 650 to the tire at 4000lbs with me in it. Its an absolute ripper.

 

[2018HellKitty]

Sounds like a blast! the hellcat is a fatass for sure. No speaker box, no groceries and absolutely empty with just me and it’s about 4700 give or take.

 

[Doublewide]

20% loss is not typical. Modern cars lose more like 10-12%. That said, 140+ IAT means your car is definitely not at full potential. You dyno it with temps 120 or less, you will pick up a lot of power. I'd say average dyno from a helcat in more optimal conditions with A8 trans is 630, give or take.

 

[beep-beep-vroom]

20% loss is not typical. Modern cars lose more like 10-12%.

Thanks for the correction...led me to this article on the subject. Drivetrain Power Loss - The 15% "Rule"- Modified Magazine

 

[Vet Rider]

20% loss is not typical. Modern cars lose more like 10-12%. That said, 140+ IAT means your car is definitely not at full potential. You dyno it with temps 120 or less, you will pick up a lot of power. I'd say average dyno from a helcat in more optimal conditions with A8 trans is 630, give or take.

Cot is not intake temps. It’s calculated cat temps. The new cot threshold is 1701*. When I had my cot turned off, I would see 1860* calculated temps and sometimes higher.

 

[Doublewide]

Cot is not intake temps. It’s calculated cat temps. The new cot threshold is 1701*. When I had my cot turned off, I would see 1860* calculated temps and sometimes higher.

Yes, I know. he said his dyno operator told him his IAT's were 140-150 during the pulls. Car was definitely pulling timing from that.