How much boost increase?
05-13-2009, 08:17 PM
#1
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How much boost increase?
My buddies got a PI vortech car that was making 10lbs with an S-trim and he upgraded to a T-trim, got a Power Pipe and upgraded to a 10% overdrive crank. Our question is, How much boost will his boost go up?
We've heard a few different thing.
Since the CFM of the S/C is increasing by 200cfm, wouldn't that increase boost? So by that logic boost would have to increase. 1000 CFM vs 1200 CFM
I would give +3-4lbs for the 10% overdrive crank pulley and 2-3 for the boost pipe.
Any thoughts? Experience preferred please, anyone can guess.
He's worried about lifting the heads from too much boost.
We've heard a few different thing.
Since the CFM of the S/C is increasing by 200cfm, wouldn't that increase boost? So by that logic boost would have to increase. 1000 CFM vs 1200 CFM
I would give +3-4lbs for the 10% overdrive crank pulley and 2-3 for the boost pipe.
Any thoughts? Experience preferred please, anyone can guess.
He's worried about lifting the heads from too much boost.
Last edited by Sxynerd; 05-13-2009 at 08:42 PM.
05-13-2009, 11:24 PM
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05-13-2009, 11:29 PM
#5
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I haz a question, is he going to spin the engine any faster? If not, maybe 6-7 PSI.
The cool part about the T-trim is that you can spin it faster than the S, or SC trims (which are now apparently their "legacy" models and aren't produced anymore)
So if you spin the engine faster, that's usually where the added CFM/boost comes from.
the S trim supposably flows that 1000CFM at 51000 RPM, and the T-trim flows that 1200CFM at 55000RPM, so I would think that if your spinning it the same speed, the boost increase would be minimal just changing to the T-trim.
So I think it would only increase boost (assuming the same blower pulley) 1-1.5PSI above the crank pulley and the power pipe
The cool part about the T-trim is that you can spin it faster than the S, or SC trims (which are now apparently their "legacy" models and aren't produced anymore)
So if you spin the engine faster, that's usually where the added CFM/boost comes from.
the S trim supposably flows that 1000CFM at 51000 RPM, and the T-trim flows that 1200CFM at 55000RPM, so I would think that if your spinning it the same speed, the boost increase would be minimal just changing to the T-trim.
So I think it would only increase boost (assuming the same blower pulley) 1-1.5PSI above the crank pulley and the power pipe
05-13-2009, 11:43 PM
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05-13-2009, 11:56 PM
#9
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I think he's going to start loosing more boost at higher RPM. Seriously, a ton.
With supercharger cams I see around 16PSI without that Overdrive (remember I have an UNDERdrive crank pulley) pulley and a bigger supercharger pulley, and that's around 7000RPM.
http://www.vortechengineering.com/su...d%20Calculator
If you check that, he'd be about 7000RPM over what the T-trim is rated for.
61,000RPM by vortech's own calculator. Not good.
That 2.9 is going to be too small of a pulley at 7000 RPM if he wants to keep the warranty
He'd be seeing about 22PSI-24PSI comparing my set up to his, with a good set of blower cams
05-14-2009, 12:00 AM
#10
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I think he's going to start loosing more boost at higher RPM. Seriously, a ton.
With supercharger cams I see around 16PSI without that Overdrive pulley and a bigger supercharger pulley, and that's around 7000RPM.
http://www.vortechengineering.com/su...d%20Calculator
If you check that, he'd be about 7000RPM over what the T-trim is rated for.
That 2.9 is going to be too small of a pulley at 7000 RPM if he wants to keep the warranty
He'd be seeing about 22PSI-24PSI comparing my set up to his, with a good set of blower cams
With supercharger cams I see around 16PSI without that Overdrive pulley and a bigger supercharger pulley, and that's around 7000RPM.
http://www.vortechengineering.com/su...d%20Calculator
If you check that, he'd be about 7000RPM over what the T-trim is rated for.
That 2.9 is going to be too small of a pulley at 7000 RPM if he wants to keep the warranty
He'd be seeing about 22PSI-24PSI comparing my set up to his, with a good set of blower cams
. I think he was already loosing boost back when he had the S trim. I didn't seem right that he was only making 10lbs with a 2.9 pulley, even if he was going through an I/C.
What exactly is your set up?
- Off topic a little. I know you tune with Sniper, I'm thinking about getting the commando do you think I should?