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Old 07-25-2001, 10:57 AM   #1
CHACHI
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Default highest amount of boost for stock 2.5

just wondering how much boost you could use on a stock 2.5 thanks!
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Old 07-25-2001, 01:05 PM   #2
zaidallas
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Location: Expected whp/torque at 25 psi : 450
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its hard to tell , you'll have to be more specific. running intercooled , with proper fuel managment and tuned right , I think no more than 12-14 psi .
zaidoun
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Old 07-25-2001, 01:23 PM   #3
mrbell
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...and it depends on the year... the 98-99 could probably run an extra couple of pounds over the 00-01 because it had a slightly lower(9.7:1 vs 10.1:1, I think) compression ratio. But amount of boost doesn't really determine power. 10lbs of boost, properly done could very well be more powerful(and almost definitely more drivable) than 15-20lbs of ragged boost. Not to mention how you apply the boost has alot to do w/ how fast it makes the car...
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Old 07-25-2001, 01:50 PM   #4
d00f
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Let's assume that tuning and fuelling are not issues. The maximum boost you can use before your engine blows apart is really dependant upon the pistons. If your pistons happen to have some slight casting imperfections they might blow at 9lbs boost. I've certainly seen a few do this. It would seem that the maximum safe boost on a stock engine is in the 5-7 lbs range. Beyond that I'd suggest going to stonger rods and low compression forged turbo pistons. You might get away with a higher boost but then again you may not. If your piston fails you're looking at a lot of dammage inside that engine.

-Michael
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Old 07-25-2001, 01:56 PM   #5
mrbell
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Agreed...
I was just saying I don't think boost is a very good way to target performance...
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Old 07-26-2001, 03:28 PM   #6
DaveK
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I thought that there were plenty of people using the TEC-II who were running 10-12 psi with good reliablity (not including the drivetrain)
Anybody care to elaborate, esp. those running high boost?
Thanks!
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Old 07-26-2001, 03:47 PM   #7
mrbell
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There are some people running around 10 psi... shiv I think is running 10 w/ a 2000 block and 99 head, so I'm not sure what the compression is. I think it's the same as the 2000 engine, and he doesn't want to go any higher on 92 octane. There are some other people claiming to run more than 10psi, but I wouldn't count on that lasting too long. 12 is probably the absolute maximum for a reliable MY98-99 on 92 octane, 10 for a 2000. I'm just speculating, tho...
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Old 07-26-2001, 04:00 PM   #8
DaveK
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Once I get the TEC installed, I'm hoping to do two setups, one at 5psi for every day driving, then another one that starts at 6 psi and ramps up to 10, then drops back down a bit at reline...but I'm sure it'll be a while before I feel comfortable with tuning at 5psi, nevermind 10.
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Old 07-26-2001, 04:10 PM   #9
mrbell
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I'm planning on the same thing... I've got my TEC-II in... now I'm waiting on the turbo kit... uhg... one lousy pipe...
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Old 07-26-2001, 04:21 PM   #10
DaveK
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Is or has anyone run the TEC-II at high altitude for racing or otherwise?
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