How much boost can a good...
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Teching In
Joined: May 2002
Posts: 32
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From: Tuscaloosa, AL
How much boost can a good... short-block take with the H/C set up for a turbo(s)? (Low Compression?) Say, 8.5:1
<small>[ March 10, 2003, 07:18 PM: Message edited by: tidemandave ]</small>
<small>[ March 10, 2003, 07:18 PM: Message edited by: tidemandave ]</small>
Re: How much boost can a good... The trick (IMO) to keeping the stock shortblock together under high HP levels is to keep the RPM low and have a good tune.
As long as you abide by what I have said above, I would feel comfortable taking the stock shortblock deep into the 500 RWHP range.
Good Luck,
Kevin
As long as you abide by what I have said above, I would feel comfortable taking the stock shortblock deep into the 500 RWHP range.
Good Luck,
Kevin
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Joined: Nov 2001
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From: Chi-Town, IL
Re: How much boost can a good... I plan to try and run 15-16psi at a point, I think I would be happy w/that...
There are issues w/heads lifting if you get farther into the boost...
But if you build a big motor to handle it, you can probably get over 20... <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
There are issues w/heads lifting if you get farther into the boost...
But if you build a big motor to handle it, you can probably get over 20... <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Re: How much boost can a good... what octane?
Im running 9.0:1 CR with 93-94 octane and get about .97* KR (with the 94 at the track)
I think i can push it to about 12psi and still be safe.
If you have the laggier 8.5:1 CR you might be able to use 15psi (or a little more) and push out more power.
Im running 9.0:1 CR with 93-94 octane and get about .97* KR (with the 94 at the track)
I think i can push it to about 12psi and still be safe.
If you have the laggier 8.5:1 CR you might be able to use 15psi (or a little more) and push out more power.
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From: Jersey boy
Re: How much boost can a good... so if i were to shift at like 5,000rpm instead of 6 and i just got a pully that would make the same hp/boost at that rpm you think the engine would live longer?
Re: How much boost can a good... Since the author mentioned 8.5:1 pistons I assume he meant a built forced induction motor.
With 8.5:1 I think you could run 12-15lbs of boost with pump gas potentially and make 600rwhp.
Might it take 20 lbs of boost? With the right combo, it should but the fuel system needs to be stepped up and you are not going to be able to do it on pump gas.
Somewhere between 15 and 20 lbs of boost you will run into some roadblocks, namely the need to use low impedance injectors and the potential issue of pegging the MAF. Right now the biggest high impedance (stock pcm only had high impedance drivers) injectors are the new Siemens 55's, which at our fuel pressure are more like 70's.
I'm building a 9:1 3.905 LS6 block with 6.0 heads that will be around 9.1:1 with MLS gaskets. I will be using head studs and will be pulleying the YS trim for 20 lbs of boost. I am building the motor to run up to 7200 rpms. I am also going to use a stock crank but will be getting it cryo'd.
With 8.5:1 I think you could run 12-15lbs of boost with pump gas potentially and make 600rwhp.
Might it take 20 lbs of boost? With the right combo, it should but the fuel system needs to be stepped up and you are not going to be able to do it on pump gas.
Somewhere between 15 and 20 lbs of boost you will run into some roadblocks, namely the need to use low impedance injectors and the potential issue of pegging the MAF. Right now the biggest high impedance (stock pcm only had high impedance drivers) injectors are the new Siemens 55's, which at our fuel pressure are more like 70's.
I'm building a 9:1 3.905 LS6 block with 6.0 heads that will be around 9.1:1 with MLS gaskets. I will be using head studs and will be pulleying the YS trim for 20 lbs of boost. I am building the motor to run up to 7200 rpms. I am also going to use a stock crank but will be getting it cryo'd.
