If you have any formula that helps compute
drivetrain changes, add them here
Horsepower:
HP= (AP x CR x VE x CID x RPM)/792001.6
AP=atmospheric pressure in psi (14.7)
CR=compression ratio (10.1)
VE=volumetric efficiency (~0.9 for the LS1)
CID=cubic inch displacement (346)
If you use these numbers, it predicts the LS1 should be at 350 HP, so the equation
works! In addition, this equation shows what can be changed to get more power:
VE is improved with intake and exhaust mods, as they help pass gas through the
motor. VE can only be above 1 if you have a turbocharger or supercharger.
CR is impossible to change without getting an LS6 (10.5) or going to the aftermarkert.
CID again is not changeable with bolt on mods.
RPM can be increased slightly, but without a different cam, the stock LS1 cam specs
mean that the torque will drop like a rock at 6000 RPM and above.
The only other variable that can be changed is AP. AP is about 14.7 for NA motors, as
this is the pressure of the air around us. To increase it we need a forced induction
system OR a ram air intake that will raise the effective air pressure of the intake!!! Now
this increase may be modest (I really don't know how much is reasonable, but I can
forsee it raising from 14.7 to say 15.2
So, assuming you use a VE of 1, you can see that without using forced induction/ram air
the best HP you can expect is about 390 HP at 6000 rpm. This may explain why many
many people see diminishing returns with bolt on mods at the dyno, as they can only get
an extra 40 HP (not bad, but not serious power gains). but if you have a VE of 1 and a
AP of say 15.2, the HP at 6000 RPM goes up to 402 HP, so a ram air setup would be good
for another 12 HP (this is roughly consisent to what GM has advertised on their small
blocks with ram air).
This equation does not address pulleys, as their HP gains are from removing parasitic drag
on the motor, so they are effectively reducing the percentage loss that occurs as power
is transferred to the rear wheels.
Cubic feet per minute demand:
CFM= (CID x RPM x VE)/3464
So if you plug the numbers in, you will find the LS1 can consume only ~550-560 cfm of
air if the VE is 0.9 (stock) and only 600 cfm if the car has mods to improve VE (intake,
headers, heads, exhaust, X-pipe)... It seems that any claims of a TB that eats 1000 cfm
are BS, as the best they can do is make the air smoother for the intake, and thus
eliminate turbulence.
Volumetric efficiency (VE):
VE= (CFM x 1728)/(CID x RPM)
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Team ZR-1
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