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Old Jan 7, 2011 | 07:38 PM
  #31  
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fyi... the s/c 3.8 and the NA 3.8 aren't the same motors. they have different specs... different compression, etc... the s/c one has much lower compression making it lose a lot of efficiency... if the s/c was added to the NA 3.8 it would get better mileage and make more power than the s/c 3.8 would

the gtp also has different gears which will effect its fuel mileage...

Last edited by spiceman; Jan 7, 2011 at 07:40 PM.
Old Jan 7, 2011 | 07:39 PM
  #32  
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Originally Posted by spiceman
fyi... the s/c 3.8 and the NA 3.8 aren't the same motors. they have different specs... different compression, etc... the s/c one has much lower compression making it lose a lot of efficiency... if the s/c was added to the NA 3.8 it would get better mileage and make more power than the s/c 3.8 would
Why do you think they lower the compression?
Old Jan 7, 2011 | 07:42 PM
  #33  
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Originally Posted by HCCAFan
Why do you think they lower the compression?
to keep the power within reason, and to make sure it will run on premium pump gas in all environments and in all different types of situations, like in 110 in the desert or with 5 300lb women in it... or maybe in 110 heat WITH 5 300lb women in it...

the NA compression is 9.5 which is fine for turbo or supercharging a street car.

the s/c is ~8.5
Old Jan 7, 2011 | 07:43 PM
  #34  
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Originally Posted by spiceman
to keep the power within reason, and to make sure it will run on premium pump gas in all environments and in all different types of situations, like in 110 in the desert or with 5 300lb women in it... or maybe in 110 heat WITH 5 300lb women in it...

the NA compression is 9.5 which is fine for turbo or supercharging a street car.

the s/c is ~8.5
What fuel do I need for a 19:1 ratio?
Old Jan 7, 2011 | 07:44 PM
  #35  
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Originally Posted by spiceman
to keep the power within reason, and to make sure it will run on premium pump gas in all environments and in all different types of situations, like in 110 in the desert or with 5 300lb women in it... or maybe in 110 heat WITH 5 300lb women in it...

the NA compression is 9.5 which is fine for turbo or supercharging a street car.

the s/c is ~8.5
How EXACTLY do they lower the compression in the Pontiac 3.8?
Old Jan 7, 2011 | 07:46 PM
  #36  
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Originally Posted by HCCAFan
OK. 3 minutes to name what car , motorcycle, quad and truck you built these for AND what SC (model) or turbo you put on it.
i don't have any pictures that i know of of the s/c cars. they are long gone and bolting on a s/c isn't really that noteworthy...

i could post more if you want... these are some of them...















Old Jan 7, 2011 | 07:46 PM
  #37  
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Originally Posted by ezab
You should sell you high compression and a supercharger idea to a car company.
The supercharger is so awesome you have to make the engine crappier to counter it's awesomeness so the earth's poles don't flip flop?
Old Jan 7, 2011 | 07:48 PM
  #38  
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Pics are worthless. I want to hear WHAT turbo or SC model specifically.
Old Jan 7, 2011 | 07:48 PM
  #39  
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Originally Posted by HCCAFan
What fuel do I need for a 19:1 ratio?
19:1 is normally a diesel engine range.

Last edited by JeepingDan; Jan 8, 2011 at 03:09 PM.
Old Jan 7, 2011 | 07:49 PM
  #40  
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5.0 intake mani on a turbo'd fox? What kind of back woods engineering is that?
Old Jan 7, 2011 | 07:50 PM
  #41  
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Originally Posted by HCCAFan
Pics are worthless. I want to hear WHAT turbo or SC model specifically.
lol... uh ok...

my shortbox has a HX40

my mustang had twin t3s and then had a single T70

the raptor had a IHI RHF4
Old Jan 7, 2011 | 07:52 PM
  #42  
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alcohol usually have a limit around 15-16:1 and ethanol has a reasonable limit of around 14:1

Last edited by JeepingDan; Jan 8, 2011 at 03:10 PM.
Old Jan 7, 2011 | 07:53 PM
  #43  
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Originally Posted by spiceman
lol... uh ok...

my shortbox has a HX40

my mustang had twin t3s and then had a single T70

the raptor had a IHI RHF4
T3 is a flange size. By T70 are you trying to say 70MM? Not with that intake mani, not for long junior.

What's a shortbox? That top pic sure as **** isn't a Holset turbo.
Old Jan 7, 2011 | 08:14 PM
  #44  
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[QUOTE=spiceman:
it WAS TWIN TURBOCHARGED. WITH t3 turbos which is common name for any t3 flanges turbo... these ones happened to be odd ball flanged turbos (not a standard t3 flange) off dodge turbo 2.2 motors... i believe they were .42/48

THEN

i built a single turbo kit for it... using a T70 turbo... it had a divided t3 flange... i don't know what the specs are... i could find out... but different people make "T70" turbos and some have different specs. mostly because the a/r ratio is .70[/QUOTE]
The .42 OR .48 you are talking about is a ratio of the compressor wheel and the exhaust wheel. Do you even know how a turbo works? That doesn't say anything about what turbo it was.

A divided flange is called twin scroll.

I know there are dif spec T70, that's why I asked you how many lb/min it flowed.

Last edited by JeepingDan; Jan 8, 2011 at 03:13 PM.
Old Jan 7, 2011 | 08:15 PM
  #45  
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Originally Posted by ezab
I am still waiting for his explanation on how a V8 drives around at lower RPMs which allows it to get better mileage.
2000 honda s2000 2.4l
18/23

2000 chevy corvette 5.7l
16/25

2000 chevy camaro 5.7l
16/25

why does the corvette and camaro get better mileage on the highway????? because they cruise around at roughly 70mph @ 1400rpms

being able to drive at a lower rpm makes a HUGE difference on fuel mileage... the ls1 engine is much more efficient at low rpms compared to the f20c... which allows the vette and camaro to cruise at under 1500rpms all the way up past 70mph... at 70 the s2k is probably running ALMOST 4k rpms



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