"it doesn't matter what turbo it is, all that matters is that it's 7 psi in the intake manifold">No, there are many other important considerations.
To expand on what I said:
"So, as you can clearly see, the stock fuel system is completely adaquate to handle ANY sized turbo/supercharger capable of maintaining 7 psig manifold pressure up to 7,000 rpm with reasonable intake air temperatures"
When you are comparing realistic forced intuction options you would usually pick something at least as capable as what you have, so to simplify the explination lets rule out anything smaller than a t28 (ie. t25 and smaller turbos). If you were to assess the air flow rate demand created by a 2 liter engine between 3k rpm and 7k rpm with 7 psig manifold pressure and realistic intake air temperatures, the fueling ability of the stock injectors and the metering ability of the stock maf are within their limitations regardless of the type of forced induction. When comparing a specific pair of turbos like the 2871 to the t28 you will see that the maximum flow rate possible is greater in the 2871. But, at 7 psi manifold pressure the t28 is well within its range of flow rates at that pressure when installed on an sr20. So, then why would you expect the 2871 to produce more power when compared to a t28 at 7 psi on an sr20? It cannot increase the pressure of the air and keep it any cooler than ambient air. So, all things being identical, a t28 on an sr20 running 8 psi will make MORE power with a stock fuel system than a car with a 2871 at 7psi and 600cc injectors and a z32 maf. Additionally, when comparing the t28 to the 2871 as installed on an sr20 that redlines at 7k rpm, the 2871 wont provide a preformance advantage until the two are push past ~ 11-14 psi manfold pressure. That is where, the torque curve will begin to decline and the power curve will flat line prior to redline on a t28 powered car. The 2871 torque curve will remain flat and power will continue to climb up to redline (disregarding other non relevant to this discussion things like cams and intake manifold geometry). This is because you have reached the limitation of the t28 compressor wheel.
If it's a pretty common fact that the stock fuel system is capable of 250 whp would you expect a 2871 to make 250 whp at 3-4 psi manfold pressure as stated above by you? Would expect a 2871 to make 250whp at 7 psi...I dont think so.
Just because the 2871 has a performance range that is superior to the t28 doesnt mean it will provide an advantage within the performance range of the t28.
Simply put
7 psi is 7 psi (comparing t28 and 2871)
14 psi is NOT 14 psi (comparing t28 and 2871)
Quote:
Originally Posted by jspaeth
OMG.......please answer this question for me.....
Would you say that you agree with the following statement:
"7 psi is 7 psi is 7 psi.......it doesn't matter what turbo it is, all that matters is that it's 7 psi in the intake manifold".
I would like a YES or a NO answer to that question.
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