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Discussion Starter · #1 ·
so from 70+ the truck feels like its running out of fuel and im not seeing any smoke at all from the exhaust when i have it on the floor. does this mean i need more fuel? or is this normal
 

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Depends on what tune you are running. But, for the record, mine will haze when to the floor at that speed.
 

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Same mine..truck does not smoke at those speeds..the turbo around 10 psi at 70 doesnt take long to light up
 

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Well, it means you don't have excessive fuel, meaning it's all being burned. That's a good thing, not a bad thing. Now, I've never been in a tuned 6.7, but my 5.9 leaves one heck of a smoke trail; wish I could have it videoed from a plane, I'm sure I could write words doing cookies in a parking lot like those stunt planes.:hehe:

On a stock truck with a heavy program, I'd expect there to be a good bit of smoke on a dig. Are you running the higher program H&S has?

I wish mine burned clean on a dig
 

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The agressive boost shouldn't be an issue up top, in fact it's probably a good deal of the reason that your burning all the fuel and not rollin coal.

What I mean by not that much of an issue is the aggressive boost isn't up top it's down low vs. RPM.

More importantly, what's your rail pressure look like?
 

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I don't think so.

Like has been said get some gauges and report back. Rail pressure could be falling on its face.
I would actually like to see some data on this and this is the perfect oportunity!

Get a rail pressure gauge installed BEFORE the fass system and take a vid of the rail pressure gauge, including the tach if you can, on a wide open run from 10 to 80 mph.

Then install the fass and do the same thing. That will put this argument to rest once and for all!
 

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I would actually like to see some data on this and this is the perfect oportunity!

Get a rail pressure gauge installed BEFORE the fass system and take a vid of the rail pressure gauge, including the tach if you can, on a wide open run from 10 to 80 mph.

Then install the fass and do the same thing. That will put this argument to rest once and for all!
I'm not trying to argue. I can see it helping. Reason being the cp3 is getting a better supply of fuel. But, I don't think it'll be a substantial amount.
 

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ill be doing this also...Im going to record today on hot 0-80 to see what my rail is ...
 
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FYI I run HotDamn w/ATT on Performance (hot) and my rail pressure cannot hold high pressure. When I floor it boost will peak at 31 psi then quickly drop off to about 22-25kpsi. H&S said I needed more fuel to the rail, more than likely the cp3 was being starved.
 
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FYI I run HotDamn w/ATT on Performance (hot) and my rail pressure cannot hold high pressure. When I floor it boost will peak at 31 psi then quickly drop off to about 22-25kpsi. H&S said I needed more fuel to the rail, more than likely the cp3 was being starved.
Do you mean rail peaks at 31kPsi? if so your relief valve may be opening and I think they have to go back to 13K to "reset" (info from Shane at Motorsport) 22 is low, 25 is more than fine...all about how fast it gets there and whether it stays there.

For ref. my rail was 24-ish on a bone stock fuel system and H&S's hot tune. I tune myself now and my fuel system isn't stock so my truck is a bad test mule for this experiment...wish I had been paying attention to all the info along the way as I built the truck though. Here's a good chance to pick up what I missed:thumbsup:
 
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