I would just like to know with the mods in the sig would it be necessary to step up in injector sizes or maybe even put in an inline fuel pump. Ill be honest when it comes to fuel delivery im pretty lost.

Thanks again guys!

 

do you have any dyno numbers? If you still have stock heads, then you are probably ok with your stock injectors.

 

You should be OK for now with the stock fuel system.

 

From what everyone else has done with that cam. I would say that an injector up grade is not required.

The best way to tell is to get a data log and confirm that your Injectors are staying belong the 80% duty cycle.

I can't find the equation to compute this right now but I know its on this site somewhere.

Edit:
Found this post by Injuneer

Duty cycle is calculated by dividing the pulse width by the number of milliseconds it takes for the crankshaft to make two revolutions.

For example, at 6,000rpm it take the crankshaft 20.0 milliseconds (mS) to make two revolutions. If you had a 17.0 ms pulse width, the duty cycle would be:

17.0 / 20.0 = 0.85 or 85% duty cycle.

To save you the calculations:

RPM---time

3,000 - 40.0mS
4,000 - 30.0mS
5,000 - 24.0mS
5,500 - 21.8mS
6,000 - 20.0mS
6,500 - 18.5mS
7,000 - 17.1mS

How high a pressure you can run depends on the type of injectors.... the stock ball/seat injectors do not like anything over maybe 60psi. The pintle style (e.g. - Bosch, FMS, SVO) are OK at much higher pressures.