VGT Compound Build

DaCajun · Jul 24, 2016

Morgan@Midwest Diesel & Auto said:
Fwiw, this thing is absolutely nuts. On the one 1300us roll I was able to get the camera on the gauges.... Around 82psi/96ebp.... 1.17-1 total ratio, which is phenomenal with anything making 80+ psi of boost. Not no mention less than 1500*... It's got a retarded amount of power left in it... Gonna need some o-rings first though.

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When ya'll O'ring these, what head gaskets do you use???

Very, very nice build BTW!!! :rockon:

Six_Sloww · Jul 25, 2016

Not bad for 1.0ms.

I had it out for about an hour last night and the entire fuel tank was very warm afterward. My low pressure light on the airdog didn't come on until about 20 minutes into the drive so I'm going to say it's definitely got something to do with heat.

It was also about 95 degrees with 80+% humidity. The secondary system just can't keep up, on the eway my iat's are close to ambient but driving light to light it quickly crept up to 150+.

I'm going to try and reduce stress on the secondary system wherever possible, so I ordered a fuel cooler last night. Should be here today or tomorrow. It's a 12x16 derale unit with a fan and -8an ports, it'll be placed right inbetween the oem fuel pump return and the tank.

I may even run a traditional trans cooler up in the bumper gap so that the secondary system is only responsible for keeping the CAC cool.. I could even run an icebox, we shall see.

I will say, it's incredible how smoke free and quick spooling this setup is, besides a faint power loss 150+ iat's really didn't even change how the truck drove which is pretty crazy.

Six_Sloww · Jul 25, 2016

Simple, cheap. With lines and fittings I'll barely have 200 bucks into it so worth a shot.

UpstateDieselGuy · Jul 25, 2016

At the point you are at I would consider that a sensible and necessary investment. Now is not the time to risk anything.

CATDiezel · Jul 25, 2016

Six_Sloww said:
My guess is it's over 140.

I let it run down to a quarter tank and while I was filling up there was what I assume to be a hot diesel vapor escaping as fuel was entering.

I'm going to start with a better fuel cooler because that's a pretty simple cost effective place to start

Hot fuel has a pretty nasty affect on lubricity and high pressure components.

The United States government did a test on the 6.7L fuel system proving the points on lubricity and the wear on injectors and pumps. Being they use the 6.7L in some of their militany vehicles or plan on doing so. Caterpillar swears up and down the loss of lubricity of the fuel is greatly lowered past 140*F. That's why they start putting the engine into a pretty hefty engine derate above that temperature.

Six_Sloww · Jul 25, 2016

Yeah 5K in injectors, 3500 in injection pumps.. Low pressure system...

200 dollar cooler seems like a worthwhile investment LOL.

I'm going to pick up an infrared thermometer after work and do some before/after testing

521turbo · Jul 25, 2016

I've found that a plate cooler seems to do a lot better job than any tube cooler. There's a lot of info out there on it.

Six_Sloww · Jul 25, 2016

Yep a plate cooler does a better job, once this is in the truck I will measure it's effectiveness.

Either it'll pass or fail. If it needs more than just this tube cooler I'll buy a nice bar and plate exchanger and just reuse the fan.

BOSS450 · Jul 25, 2016

I run then next size up as a trans cooler. I'm sure that will be plenty of cooling for fuel

Six_Sloww · Jul 25, 2016

The stock fuel cooler is about the size of a wallet, this is a hell of an upgrade lol.

CATDiezel · Jul 25, 2016

Six_Sloww said:
The stock fuel cooler is about the size of a wallet, this is a hell of an upgrade lol.

I think your definitely on the right track!

sootie · Jul 25, 2016

do you have any idea why the fuel is getting so hot? i concur that adding the fuel cooler will help, but why is it so hot?

i mean this was never an issue on duel fueled six fours which moved quite a lot of fuel.

BOSS450 · Jul 25, 2016

Mine gets hot. I'll be adding one to my truck. I don't think people even noticed it though. If I keep the tank full it's not bad. But at the track it gets hot.

Six_Sloww · Jul 25, 2016

6.4 fuel cooler

6.7 fuel cooler

Not to mention its cooled by the secondary system which cools the cac and transmission oil. So you're cooling your fuel with warm water, it doesn't really do anything lol.

Six_Sloww · Jul 25, 2016

Also the 6.7's see even higher injection pressures. Cruising speed I'm at 22k rail. On the eway doing 80ish my rail pressure is 28k

sootie · Jul 25, 2016

Six_Sloww said:
Also the 6.7's see even higher injection pressures. Cruising speed I'm at 22k rail. On the eway doing 80ish my rail pressure is 28k

holy!

BOSS450 · Jul 25, 2016

Not trying to be a stickler but the 6.4 is air-water and water to fuel cooled too. The 6.4 is the same size coolant to fuel.

Six_Sloww · Jul 25, 2016

BOSS450 said:
Not trying to be a stickler but the 6.4 is air-water and water to fuel cooled too. The 6.4 is the same size coolant to fuel.

You're right, I forgot that lol.

But the fuel cooler on the 6.4 is standalone correct? So it's sole purpose is to cool fuel where mine gets whatever temperature the secondary system is.