hx35 exhaust flange

[993500]

Hello everyone I just got a hx35 turbo for my 99 gmc 3500 6.5l turbo diesel. I was wondering if if matters if the exhaust flange is divided or if it has to be the open one like my gm8 has. I already installed a 4 inch turbo back exhaust with a 4 inch down pipe still have to do the crossover pipe. Also looking for installation tips for the hx35 any information would be greatly appreciated.

 

[FellowTraveler]

Hello everyone I just got a hx35 turbo for my 99 gmc 3500 6.5l turbo diesel. I was wondering if if matters if the exhaust flange is divided or if it has to be the open one like my gm8 has. I already installed a 4 inch turbo back exhaust with a 4 inch down pipe still have to do the crossover pipe. Also looking for installation tips for the hx35 any information would be greatly appreciated.

It's dual scroll and works great on the 6.5td Holset or CKO type hx35 spool faster than other same sized brands, if it's t3 just bolt on.......

 

[993500]

Thanks for the reply. Looks like I might have to spin the exhaust to line up with my down pipe which is a 3 inch not 4 inch as stated earlier.

 

[pacificdrumma]

Yup, they bolt on. Some people will take a razor or dremel and grind down the divider so its tapered.
You will most likely need to rotate the rear and center sections of the turbo to get it to line up on your truck.

 

[993500]

Thanks everyone hopefully I'll have it installed this weekend just have to remember to set the waste gate to around 15 psi.

 

[FellowTraveler]

Thanks everyone hopefully I'll have it installed this weekend just have to remember to set the waste gate to around 15 psi.

That 15 psi will yield 29.7 psi @ sea level - loss from CAC/IC and intake that's just over 2.0 pressure ratio. I run 2.5/2.9 max pressure ratio w/big HX40w.

 

[Jorge6.5]

Why do you have to set it to 15psi?

 

[6.5L]

Knife edging the dual scroll housing to taper it in for better flow isn't something I'd recommend. Knife thin metal and repeated heat cycles, and it's sure to crack.

 

[pacificdrumma]

Knife edging the dual scroll housing to taper it in for better flow isn't something I'd recommend. Knife thin metal and repeated heat cycles, and it's sure to crack.

x2, I didn't do it to mine, but I have seen it done on here and other forums. My HX35 spooled like a stock GM turbo.

 

[6.5L]

Yeah, most people who knife edge are Cummins guys who think they know something. Really not needed. Especially on a Cummins. Divided anyways

 

[993500]

I have heard that 15 psi is the highest boost a stock 6.5 can handle without modification. I already have a boost gage and will install a egt gage when I do the crossover pipe.

 

[FellowTraveler]

I have heard that 15 psi is the highest boost a stock 6.5 can handle without modification. I already have a boost gage and will install a egt gage when I do the crossover pipe.

Not true, I run up to 2.9 pressure ratio w/big HX4OW 4" IN/OUT on stock block w/o studs that's 42.63 psi total and on the boost gauge 27.93 psi. Pressure ratio is measured to include the air pressure you are at so I'm at sea level and that is 14.7 psi then you add whatever boost you are running to get the pressure ratio, most turbo maps show pressure ratio.