Hellcat Cat Delete and Gear Swap

[jchambers]

Looking to improve our 1/2 speeds this season with the 2016 Hellcat on E85 and 17psi of boost. We're going to eliminate the cats to avoid cat temp fueling and swap to a 3.09 gear.

For the cat delete, I've eliminated COT/EOT Enrichment (0.0), set a minimum FA Limit (FA Max), bumped the Converter Overtemp and Exhaust Overtemps up to 1850F (along with the targets), and gone through the Engine Diagnostics and unchecked everything to do with Sensor 2 errors. Sound right? Do I need to catch anything under the Close Loop Enable Rear?

We're also dropping a 3.09:1 differential in it. There's nowhere that I see to make a gear correction so I'm assuming its buried in the Trans controller somewhere. Anything that can be done to correct the speedo, shift points, etc?

[06300CSRT8]

IF and only IF HP has enabled gear tuning it is in the special functions of the scanner, not the editor.

I would go higher than 1850 on COT overtemp if it were me, until you have logged a full 1/2 pass, youd be surprised what the PCM will model out for exhaust temps.

[jchambers]

Thanks. 1850F was purely arbitrary so I'll bump it up.

[Higgs Boson]

Why wouldn't you just max out the converter temp to disable COT no matter what if the cats are gone?

[brr]

agreed with Higgs, would the maxing of the COT basically disable it? I personally still have cats installed but after doing a WOT run i'm tired of the sulfur smell of the cats......

[jchambers]

Worked just fine as I originally set it up, even at 1850F. No CAT/EOT enrichment and no errors. Fueling was spot on. 816 RWHP/ 760 RWTQ on my MD.

[06300CSRT8]

Worked just fine as I originally set it up, even at 1850F. No CAT/EOT enrichment and no errors. Fueling was spot on. 816 RWHP/ 760 RWTQ on my MD.

Good power, but I guess I am confused, youre tuning for a 1/2 mile race correct? Going to rack up temps a lot more than a dyno pull.

[Ohioc5]

I installed the 309 rear diff in my '16 Hellcat. No changes to the tune necessary for 2.62 to 3.09 swap.

[Hpindy]

On a 2018 Hellcat what tables are modified when the cats are removed ? For now I put O2 simulators in.