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Premium Member
2007 AWD 3SS
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8,588 Posts
Discussion Starter #1
I think I might have a go at it.

The other day my bud was watching and noticed when I revved up it was puffing black on accel.

I put the tune back to stock thinking maybe the superchips curves were too rich...nope, did it stock too. I measured my fuel rail pressure before and it was 63 PSI, didn't pay much attention to it before. So now I'm thinking, it's supposed to be 58 PSI, so I have a pressure regulator problem or a tight regulator...either way I really don't think I want to take it to Chevy for the monkeys to play with, so I may be recalibrating the injector curves for the increased pressure.

Kind of explains why I always though the carbon buildup inside the tips was more than it should be, as well as why I always got crummy mileage, I mean, before the tune it was 11.5 MPG.

I have a guide someone wrote on calibrating injector tables, might try that just to see. I also have the stock air filter back on at the time being so I might change that back to the other filter and relocate the MAF again. That made a 2 MPG difference before so I must help get a little more air through the MAF without leaning it out as bad as some were saying relocating does.

Thoughts?
 

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Registered
06 TBSS 2WD
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346 Posts
I actually thought the fuel pressure was supposed to be 4.1 bar...which is like 62-63 psi. But I've heard 58 psi also.....
 

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Premium Member
2007 AWD 3SS
Joined
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8,588 Posts
Discussion Starter #3
If that's the case, why would GM design it to run too rich on accel?

I mean, does every TBSS puff black smoke on revving up?
 

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2006 TBSS
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820 Posts
Don't mess with injector tables when you have stock injectors.. Are the injector tables stock? What you are looking for is found in transient fueling. I actually get a rich dip after WOT and lean spike before.. However, this can just be my wideband.. I'm 99% that its my wideband on the lean spike, as the exhaust takes a fraction of a second to reach the sensor.. the sensor averages and reports data to the eio which then averages the data again.. heh.. The sensor always sniffs at 300hz, the analog output rate is changed to 1/12th.. and the hpt eio is 40fps max.

Drove me nuts at first. I then learned quite a bit about transient fueling. :D..
 

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Premium Member
2007 AWD 3SS
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8,588 Posts
Discussion Starter #6
I havent messed with any fuel tables so far and the superchips tables look like the stock tables.

What do you suggest doing?
 
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