[Hellcat.Muk]

Hey guys question on the performance pages I pulled up the dyno it comes with and when it shows how much HP in putting out... I punched it and it was showing 640-677 and as I was going into 5 gear it hit 702 that's the highest I've seen it hit on a cold night. My question here is what is that? Is that crank power or whp? What is that dyno showing? I have a 2021 hellcat 5k miles widebody crank hp is 717. I'm asking out of curiosity here is the picture I'm still a new hellcat owner. Coming from a scatpack....

I also noticed when I went catless it lost power it would never go over 638 I put the cats back on its showing 650-677 consistent and even 700 sometimes now

I

 

[Marc S]

you removed the cats? Why? they support well into 900 HP plus its a federal offense with huge fines if caught.

If your tuned and running off road I could see it but there are plenty of 1000 hp builds still running cats.

 

[Shelbyguru]

Welcome to the Hellcat World! That Dyno number is a calculation of Crank HP based on the data from a few sensors.
The HP loss from removing the cats was due to a reduction in back pressure. When others put a good set of headers on their Cat, they usually loose about 2 psi of boost. When you get a "tune" to compensate for the reduction in back pressure, you will most likely see a gain and not a loss. There is more to be gained on these engines (supercharged) from a reduction in inlet restriction than the exhaust side. As an example, if you port the SC Bearing Support Plate along with a ported snout and go with a 'larger" Throttle Body (now that your inlet snout is larger than 95mm), you can see gains of 60 to 80 HP! FYI: The snout from the factory is 95mm in diameter however, the original Throttle Body is only 92mm. So, if you can find someone that upgraded to a 100mm or 105mm or 108mm TB (with a ported snout) and had a actual ported 95mm original TB for sale, go for it! Please be aware that you want a 95mm Throttle Blade and NOT just a ported inlet BEFORE the stock throttle blade. Some companies are playing that "game" so be careful and read up!