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Discussion Starter #1
I have a bone stock LB7. Out of curiosity, what is the normal turbo boost of this engine in psi or inches of mercury?

And if the engine is chipped, how much is the boost raised?
 

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Depends on elevation and outside air temp to a lesser degree. At 3000 ft., I can't make more than 18 PSI according to my gauge. Being close to sea level, you should see 20-21.
 

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I can regularly hit 26psi. And my chip does not raise boost as far as i know.
 

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Discussion Starter #5
Thanks for the info.
 

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Full Banks Six Gun kit on my truck and I have never been above 22 0r 23 psi.
 

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Chips do not raise boost. Adjusting your wastegate does. A chip will make it easier to reach peak boost levels.
 

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With the help of the Neens on here, I am getting mine to go up. it is raining today, so testing went out the window AGAIN! Rain for two days, but tomorrow is supposed to clear up!
 

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Up to 24 at WOT with Predator on 65 and outdoor temp -30C. At warmer temp 22 max.
 

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I have to push mine pretty hard to see more than 18 or 19 psig
 

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I have yet to see anything over 20PSI on my boost gauge. This is even towing a 13,500 lb 5th wheel over 10,000' as well as close to sea level. Truck is 100% stock.
 

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I get up to 28. Set the edge warning at 28 and it beeps at me every once in a while if I'm on it hard, oh and I live at 8000 feet..... 18-20? Seems low? No?

JP
 

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azduramax04;1661096; said:
I get up to 28. Set the edge warning at 28 and it beeps at me every once in a while if I'm on it hard, oh and I live at 8000 feet..... 18-20? Seems low? No?

JP
18-20 is where GM sets their waste gate to dump. Do you have guages or just the edge? If its telling you 28 and you don't have anything to increase boost there is something wrong with your edge or wastegate. I would be worried about 28 psig if I hadn't done anything to get it there. As mentioned earlier - the programmers won't do anything for our boost. It is manually controlled by the wastegate. I haven't used the edge or even looked at it but does it report absolute psi, ie do you have to subtract the atmosphere 14.7?
 

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at about 20 psi, the waste gate probably isnt moving. you dont adjust the waste gate to get more boost on factory settings, just not enough fuel for more boost. a ppe boost fooler will do nothing on a stock truck. the waste gates will allow around 29-32psi(more like 29-30 but rare cases of higher). to get more, you need to modify the hose, which is highly not recommended.

and yes i get a kick out of all these statements!

now the vvt are all together different. dont know much about those
 

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moss022;1661346; said:
at about 20 psi, the waste gate probably isnt moving.
and yes i get a kick out of all these statements!
If you are talking about me, please explain to me why with my efi live I can rap it up to about 20psig in stock or high fuel. It runs right up to 20 and stops. Sure seems to me that it is set to dump our ar @ 20 psig.
 

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then something isnt right. the only modifing i did to mine was tapping in post intercooler. at best i saw a max of 31psi. normal stock driving most likely will not move it. if you want to test it, hook a regulated air line up to it and see when and how it moves(you will see what i am talking about)
 

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Unless I am completly missing something, please explain the purpose of Kennedys boost controller and or the bighead wastegate. From what I understand the wastegate is set to start to dump before 20psi is attained and will try to maintain that. I can see a guy maybe getting higher boost levels by dumping the pull at the high end of the pull but I don't think a guy will get consistent boost levels without controlling by some other means. The pressure on the hose is not the only controlling factor on when the wastegate dumps.
 
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