Thank you Cribbj, that is one of the clearest answers I have gotten so far. I also plan on installing the Lextreme Stage II head. How much horsepower should I expect at full boost with the 2.2 litre opcon-autorotor twinscrew?
Bottom End/ Cylinder Head
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The 1UZFE EGR Delete Kit is available for sale here.
Thank you Cribbj, that is one of the clearest answers I have gotten so far. I also plan on installing the Lextreme Stage II head. How much horsepower should I expect at full boost with the 2.2 litre opcon-autorotor twinscrew?
Here are a few photos of this supercharger & manifold mounted on my 1UZ. In terms of how much boost you can get out of it, you can figure it's producing 2.2 litres of air for every revolution, while the engine is pulling in 4 litres of air every other revolution, or for sake of calculation simplicity, we can say 2 litres of air each rotation.
So this supercharger will produce 2.2/2.0 = 1.1 times as much air as the engine needs, IF it's rotating at the same speed as the engine, which it's not, it's rotating faster.
The supercharger is always being overdriven by the engine, because its pulley is smaller than the engine's pulley. So to find out how much air the supercharger is really putting out, you multiply the 1.1 above by the ratio of the pulley diameters.
Example:
Supercharger pulley: 91mm (about the maximum size pulley you can run in a Lexus or Supra, to not have hood interference)
Engine Dampner: 157mm
Drive ratio: 157/91 = 1.73
So the final boost ratio is 1.73 * 1.1 = 1.903
Multiply this by 14.7 (atmospheric pressure at sea level) and subtract 14.7 from the result, and you'll find your boost pressure is around 13.2 PSI. Of course this doesn't work if you live up in the mountains, but you can substitute your own atmospheric pressure.)
This is a very simplified formula and doesn't take into account efficiencies, heating of the air, VE, etc. But it's good for quickie calculations to do pulley sizing.
Now if the engine is turning 6500 RPM max, and the supercharger is spinning 1.903 times that, then it's spinning around 12,300 RPM. Since this charger has an upper limit of 15,000 RPM, you can change the drive ratio to 15,000/6500 = 2.31. Multiply this by the 1.1 displacement ratio then calculate boost and you'll have 2.31 x 1.1 = 2.54. (14.7 x 2.54) - 14.7 = 22.7 psi of boost, maximum.
Note, this is probably only a theoretical number, because it would require an extremely small supercharger pulley of 157/2.31 = 68mm, which probably wouldn't be available in the real world, and if it were, there would be belt slippage problems with it, etc.
BTW, this isn't the final configuration of my motor, we're just getting it prepped to run on an engine dyno.
or if you wont something popping its head out of your bonnet you could put a GM 6-71 S/C with a bug catcher on top :bling: Richwood does a kit
PWD's is a 2.3L Whipple. It's hypronet who has the big one (and it's 3.3L, not 3.0 like I originally thought).
He did post some info and pics of this 3.3L monster in PWD's thread here: http://www.lextreme.com/forums/showthread.php?t=8967
Thank you Cribbj, that is one of the clearest answers I have gotten so far. I also plan on installing the Lextreme Stage II head. How much horsepower should I expect at full boost with the 2.2 litre opcon-autorotor twinscrew?
Here are a few photos of this supercharger & manifold mounted on my 1UZ. In terms of how much boost you can get out of it, you can figure it's producing 2.2 litres of air for every revolution, while the engine is pulling in 4 litres of air every other revolution, or for sake of calculation simplicity, we can say 2 litres of air each rotation.
So this supercharger will produce 2.2/2.0 = 1.1 times as much air as the engine needs, IF it's rotating at the same speed as the engine, which it's not, it's rotating faster.
The supercharger is always being overdriven by the engine, because its pulley is smaller than the engine's pulley. So to find out how much air the supercharger is really putting out, you multiply the 1.1 above by the ratio of the pulley diameters.
Example:
Supercharger pulley: 91mm (about the maximum size pulley you can run in a Lexus or Supra, to not have hood interference)
Engine Dampner: 157mm
Drive ratio: 157/91 = 1.73
So the final boost ratio is 1.73 * 1.1 = 1.903
Multiply this by 14.7 (atmospheric pressure at sea level) and subtract 14.7 from the result, and you'll find your boost pressure is around 13.2 PSI. Of course this doesn't work if you live up in the mountains, but you can substitute your own atmospheric pressure.)
This is a very simplified formula and doesn't take into account efficiencies, heating of the air, VE, etc. But it's good for quickie calculations to do pulley sizing.
Now if the engine is turning 6500 RPM max, and the supercharger is spinning 1.903 times that, then it's spinning around 12,300 RPM. Since this charger has an upper limit of 15,000 RPM, you can change the drive ratio to 15,000/6500 = 2.31. Multiply this by the 1.1 displacement ratio then calculate boost and you'll have 2.31 x 1.1 = 2.54. (14.7 x 2.54) - 14.7 = 22.7 psi of boost, maximum.
Note, this is probably only a theoretical number, because it would require an extremely small supercharger pulley of 157/2.31 = 68mm, which probably wouldn't be available in the real world, and if it were, there would be belt slippage problems with it, etc.
BTW, this isn't the final configuration of my motor, we're just getting it prepped to run on an engine dyno.
rx7 s1 1uz
New Member
or if you wont something popping its head out of your bonnet you could put a GM 6-71 S/C with a bug catcher on top :bling: Richwood does a kit
XR8tt
Active Member
PWD's is a 2.3L Whipple. It's hypronet who has the big one (and it's 3.3L, not 3.0 like I originally thought).
He did post some info and pics of this 3.3L monster in PWD's thread here: http://www.lextreme.com/forums/showthread.php?t=8967
