Check this out:
http://www.sr20-forum.com/showthread.php?t=9874
A.)
B.) Answer to this one can be found
here, but I included the quotes
Won't moving the fuel injectors 1/4" mess up the "aim" of the fuel stream and cause driveability and mileage problems? Doesn't the injector have to hit the back of the intake valve perfectly to work properly?
This was an initial concern of Outlaw Engineering also. After investigation, testing, and real world experience, it would seem that injector pulse placement is not as critical as some may feel. For example, most modern 4 valve/cylinder engines have two intake valves and only one injector per cylinder. If you take a look at some of these injectors, many have a "splitter" that breaks the fuel shot into two streams to shoot it in the general direction of the intake valves. Hardly a precision aimed component. There have been racing organizations that successfully move the injectors several inches from the stock position without negative effects. With literally thousands of ThermoBlok spacers in the field, this has never posed a problem.
Won't the additional length/volume added to the intake manifold mess up the power curve (or VRIS valve resonance points)?
The 1/4" (6.35 mm) addition to the runner length will indeed shift the torque curve to the left slightly, about 50 RPM. This has actually been proven to be a benefit as it helps to restore some of the torque lost due to the addition of larger intakes and exhausts. Take a look at the dyno plot on our TECH page (or on your specific vehicle application page) and you will see that although the torque curve is shifted, power is up across the entire power band.
How they work