tici

iTrader: (1)

Using the Smokemup formula to calculate the fuel injectors size I come up to 34.5 Lb/hr.

Values:
400 HP (Vortech rating for the non intercooled kit)
max duty cycle 80%
brake specific fuel consumption = 0.55

http://www.smokemup.com/auto_math/fuel_injector.php

Vortech supplies 38 Lb/hr injectors for both kits: 400 and 450 HP: the Smokemup formula isn’t that bad.

Here my questions:
Is 80% duty cycle too high?
Injectors are normally rated at 43 PSI, my system works with 59 – 60 PSI. Can I go with smaller injectors?
What happens if I buy too big injectors?
I could have a flow matched set of Lucas 42 Lb/hr, the second choice is a set of flow matched Bosch (36 Lb/hr), part number 0280155811.
What would you take?
Price is not an issue.

Thank you!

Stefano

injectorman

80% is the max you want to run most injectors.
Go with a 42 lb setup. at 59 psi they will be 52.3 #lb hr. The 42's are still at a good price and gives you room for upgrades.
Running too big of an injector can cause idle problems and drivability issues. The newer injectors up to 60lb high impedance can do really well on a street car with losing drivability. They just take more time to fine tune.
hope this helps.
There are some good formulas here also
http://www.rceng.com/technical.htm

tici

iTrader: (1)

Thank you for the replay.
So you don't think 42 is too much? I really don't have a clou!
The car is a daily drive and it should really run like stock unless I mash the pedal
Thank you for the address: I know this company. Looks professional but I never got an answer when I asked if they ship oversea...