question on straight piping a 6.4

[suzukiracingbr]

i am sure this question been asked already but i was not able to find it... do you see any problems with straight piping a 6.4? my friend works at a place and they have tons of stainless mandrel 4 inch piping he can get and he will tig a exhaust for 350 for me... if i get all the sensors back on the exhaust have you guys heard of any problems? i just installed a sct tunner but i do not have the dpf delete tune on it...i was taking about getting a custom tune after exhaust... will i see a big gain on hp and fuel economy?

[dieselkane]

Yes you can straight pipe it, but you will need a DPF delete tune of some sort. A standard DPF ON tune will not work. Yes you will see MPG gains, lower exhaust temps, all sorts of good things.

[WakemanLM]

couple of the main things that Deleting the DPF will do is:

#1 It will greatly decrease the EBP (exhaust back pressure) and EGT. (exhaust gas temperature. The EBP from the factory on the 6.4 is WAYYY to high and puts unnecessary stress on that motor. A diesel needs to breath (not be choked). EGT during regen can reach temps well over 1000 degrees. Get the DPF delete on, get some sort of DPF delete tune.

While you are at it I would get a set of egr blockoff plates (maybe your Buddy can make them too) and delete the EGR (Exhaust gas recirculate). This will eventually cause you problems when you tune the truck if you dont block off the EGR and disable it with the tuner... It will coke up and stick. (its pretty useless anyway). cobbsdieselperformance.com (who i use) can send you a set for like 40-50 bucks.
I deleted my dpf, did a cold air AFE, EGR delete plates,Magnaflow XL 4" exhaust. SCT touchscreen extreme and ran full synthetic Green Oil with AFE filter. The truck loves it (best oil I have ran so far). Also U.S. Lube 8oz per tank of fuel.

MY MPG went from 10 to 18-20 (if you stay out of it). MY EGT was cut in half, MY engine ran a bit cooler, my power is HUGE, The truck runs soooo much better.

Sorry for the lengthy post. This combination seems to run the best for me.

[08spartan250]

pretty much exactly what they said. you wont run into any issues if you get the sensors back in there and get a DPF OFF tune. and you'll see a big drop in EGTs. you'll get a decent increase in horsepower and your MPG should increase quite a bit. the DPF absolutely destroys fuel economy. i went from 11 on the highway to about 18-20 with straight pipe and spartan.

[suzukiracingbr]

thanks alot for the info, another thing i was looking at is the intake, should i buy a cold air intake? it seems like stock set up is good besides the filter...should i expend 300 on a full intake or 100 on the k&n filter?

[08stroker250]

Don't use K&N products. I would get either an S&B intake or AFE intake.