Ok im ready to go on a turbo and exhaust upgrade. As for the exhaust im thinking five inch straight out the back? Or is four inch better?The turbo part i have no clue. My egt is always real high. Like seven eight hundred just driving around. I seem to remember seeing a thread somewhere where someones turbo actually cooled down egts when it spooled up.Not looking for horsepower specifically, but ill take it. more for a cooler machine. Also do some towing but not alot. Thirty to fourty boost is enough for me.Current turbo is hy35 stock exhuastPlease let me know, i have the money but winters comin so i need to spend now before motocross starts and i waste money on another new bike

HX35W turbo would be a bigger upgrade than the exhaust. Remember I'm still 3" without issues even hauling trailers. So I would point the finger more so at the turbo before the exhaust.

It's air flow that controls the Exhaust temps. I think 5" is overkill. Don't forget the air filter, air has to get in, before it can come out.

5" is pointless and I probably saw 0 degree drop stepping up to 4"Only real way I've seen good temp drops is a better turbo . For a mostly stock truck that means Hx35wHe351cwS300 super-b

I replaced my exhaust because the OEM rusted out. First the tail pipe devoluped lots of small holes, then disconnected near the back of the muffler... I removed it because it was bashing the axle & the bed... only a matter of time before it damaged something. I figured I didn't need the tail pipe as the back of the muffler was well aft of the cab & passengers, so I ran another year like that. Eventually the whole rear of the muffler can fell off. (Note the OEM head & front pipe are larger... I think mine might have been 3 1/2"... than the tailpipe... maybe 3" on my truck)I decided I wasn't going to replace it ever again. I bought Stainless. It was 4". The "muffler" was a straight through short "glass pack" style. It sounded nice running empty but was pretty loud towing heavy... wife wore ear plugs... I feel it was a waste of money. I ended up adding an additional SS 36" FTE swirl resonator as far forward as I could get it. It's not restrictive & does help kill the drone towing. If I was starting from scratch, I might just go with the FTE & omit the muffler which would offset the cost.Russ