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The Terminator
Engine/Tuning
17 psi
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<blockquote data-quote="Black2003Cobra" data-source="post: 4904559" data-attributes="member: 3159"><p>Palehorse – Your last sentence says it all. Since no one has the compressor maps, no one can give you an answer. I'm sure the new 3.4L is a great SC, and no offense to the previous poster, but to see an increase of >45 rwHP (650-605) would mean an increase of more than 45/0.85 ≈ 53 hp at the crank. And a reduction of SC drive power that large would require an unrealistic increase in adiabatic efficiency, AE. So don't expect that large a gain.</p><p></p><p>From the available maps, what we <em>do</em> know is that the old 2.3L Whipple has a total AE of around 56% at around 17 psi and the commensurate flow rate. (AE is a function of pressure ratio and blower speed or flow rate). This translates to an estimated drive power of around 118 fwHP (crank HP) for those conditions. So even if the new blower’s adiabatic efficiency were 100% at that boost pressure and flow rate, (which it absolutely can not be), that would mean the SC drive power would drop to 118*0.56 = 66 fwHP. Hence, that translates to a gain of (118-66) = 52 fwHP or 0.85*52 = 44 rwHP. But since a total AE of 100% is impossible, (unless someone can figure out a way to break the second law of thermodynamics), that won’t happen. So again, no offense, but a gain of >45 rwHP just isn’t going to happen.</p><p></p><p>If you want a guess, I don’t think the total AE could/would be much higher than 60-65%, or so. At the same conditions (boost and flow rate), a total AE of ~65% would translate to a SC drive power of around 66/0.65 = 101 fwHP, which only means a gain of 0.85(118-101)=14 rwHP. Heck, even an AE of 70% would only translate to a gain of ~20 rwHP, (and an AE of 70-75% is centri territory!) So don’t expect to see that big a difference with just a blower swap at the same boost pressure and with the same tune, etc.</p></blockquote><p></p>
[QUOTE="Black2003Cobra, post: 4904559, member: 3159"] Palehorse – Your last sentence says it all. Since no one has the compressor maps, no one can give you an answer. I'm sure the new 3.4L is a great SC, and no offense to the previous poster, but to see an increase of >45 rwHP (650-605) would mean an increase of more than 45/0.85 ≈ 53 hp at the crank. And a reduction of SC drive power that large would require an unrealistic increase in adiabatic efficiency, AE. So don't expect that large a gain. From the available maps, what we [I]do[/I] know is that the old 2.3L Whipple has a total AE of around 56% at around 17 psi and the commensurate flow rate. (AE is a function of pressure ratio and blower speed or flow rate). This translates to an estimated drive power of around 118 fwHP (crank HP) for those conditions. So even if the new blower’s adiabatic efficiency were 100% at that boost pressure and flow rate, (which it absolutely can not be), that would mean the SC drive power would drop to 118*0.56 = 66 fwHP. Hence, that translates to a gain of (118-66) = 52 fwHP or 0.85*52 = 44 rwHP. But since a total AE of 100% is impossible, (unless someone can figure out a way to break the second law of thermodynamics), that won’t happen. So again, no offense, but a gain of >45 rwHP just isn’t going to happen. If you want a guess, I don’t think the total AE could/would be much higher than 60-65%, or so. At the same conditions (boost and flow rate), a total AE of ~65% would translate to a SC drive power of around 66/0.65 = 101 fwHP, which only means a gain of 0.85(118-101)=14 rwHP. Heck, even an AE of 70% would only translate to a gain of ~20 rwHP, (and an AE of 70-75% is centri territory!) So don’t expect to see that big a difference with just a blower swap at the same boost pressure and with the same tune, etc. [/QUOTE]
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