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Discussion Starter #1
Heard this the other day and was just wondering if it was true, for every 10lbs of boost you have 100 hp, i can kinda belive it b/c im hittin around 23 or 24lbs stock so that would be 240hp and that sounds about right for the rear wheels. may not apply to every application though.
 

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So ben was making over 500hp on fuel when he accidentally ran his LLY turbo in the low 50s for psi??

Also, rules of thumb are worthless.
 

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Seems to be a good rule of thumb for the dodge guys.....but the duramax it dosnt really work for. I was about 30psi and 500 to the rears......

IIRC the stocker LBZ is around 20 PSI and 300 to the rears.....
 

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Discussion Starter #5
Yeah the guy i heard it from does deal with mostly dodges, i didnt know if it applied to our trucks or not.
 

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There is no replacement for displacement.
 

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Seems to be a good rule of thumb for the dodge guys.....but the duramax it dosnt really work for. I was about 30psi and 500 to the rears......

IIRC the stocker LBZ is around 20 PSI and 300 to the rears.....
If you are 500 RWHP at 39 lbs of boost, you can use percentages for a guesstimate of the power you are producing at 19.5 psig being 250-300. Boost is dependant on fuelling.

Of course we all know 500 horse can make more boost than the stockers can move air for, but the % value will be close.

Be it CTD or DMX the rule is the same.

Of course, I only know that from my own 1/4 mile times and time on a dynojet while only building 35 of 55 psi of available boost. Yet running much faster ET and MPH than before the twins....

Before Twins... 550 rwhp dyno (39 psig stock IHI) [email protected] mph (39psig)

After Twins... 550.5 rwhp dyno(34 PSIG SSTurbo) [email protected] mph. (58 PSIG)

There it is.
 

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I have an engine at work making 850bhp running roughly 37 lbs of boost at the intake, of course that engine flows roughly 6500lbs of air per min. So i'm not finding that fact true on solely a boost basis.

As Juice mentioned the total volume of Air at a given temp and pressure, fueling, and of course displacement all play their parts.
 

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I have an engine at work making 850bhp running roughly 37 lbs of boost at the intake, of course that engine flows roughly 6500lbs of air per min. So i'm not finding that fact true on solely a boost basis.

As Juice mentioned the total volume of Air at a given temp and pressure, fueling, and of course displacement all play their parts.
Sneak that bastrd out piece by piece in your lunchpail, and lets build a pulling truck! :ro) :D
 

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that engine is a freakin monster, come by L sometime and i'll let ya take a peak. It's running twin s300's on it. Pretty close to the BD's we use.
 

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i heard that for every 7 lbs of boost it adds 50% of the hp engin if it had no turbo. so at 14 lbs of boost it would double the power of the engine. do not know if there is any truth to this but this is what my friend with a grand national was telling me.
 

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i heard that for every 7 lbs of boost it adds 50% of the hp engin if it had no turbo. so at 14 lbs of boost it would double the power of the engine. do not know if there is any truth to this but this is what my friend with a grand national was telling me.
True only for a gasser. Gassers need added fuelling to avoid lean conditions. over lamda=1 for necessary cooling

Gas engines make their best HP potential at L=1, but adding boost still needs the fuel to avoid holing the piston.

Diesel's work in reverse. Lean = low EGT, no piston melt. Rich = High EGT and piston melt.

No free lunches. Fuel and boost needed for both engines. Both a delicate balance but at opposite ends of the fuel spectrum of rich and lean
 

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got juice hit it right on the head.:exactly:
 
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