GSXR1000 Fuel Rail flow

[K2e2vin]

I just measured the inside orifice of the GSXR1000 fuel rail; its 4mm...would this be enough to fully support 230cc@40psi(the rating of the injectors)? i plan on running it at 45psi anyways... If 4mm is too small, im going to have a machine shop bore it out; would 1cm be enough?

 

[phyregod]

Should work just fine. 230cc's in a minute isnt much at all. But I would assume that you are running 4 on a fuel rail? which would bring you to 920cc's per minute.

Assuming the following examples given by AEM, (your 4mm fuel rail converts to .157 inches)
If .344 inches can support 499 HP, and .562 inches will support 1100 HP, Then .157 inches will support 228 to 307 HP.

SO... I'd bore that baby out if I were you. Just to be safe. 1 cm would be fine, it would support around 500HP. And if you are pushing more than that on a bike, you're gonna die anyway, so what do you care??

Just my two cents.

Up to 499 HP .344” hose -6AN

500 - 799 HP .437” hose -8 AN

900 – 1100 HP .562” hose -10 AN

The final link in the fuel delivery system is the fuel rail. The fuel rail should be consistent with, or larger than, the hose size. The additional capacity of a large-diameter fuel rail helps to dampen the pulsations created by the fuel injectors and ensures even fuel delivery under all conditions.
Fuel Pressure Regulator and Pulse Dampener
The fuel pressure regulator maintains a constant pressure across the fuel injector. The inlet manifold pressure varies with throttle angle, and engine speed. Small throttle angles and high engine speed produce low manifold pressure (high vacuum). While high throttle angles and low rpm give high manifold pressure. In addition to these conditions, low manifold pressure is associated with idle and high manifold pressure is at full throttle. It is the fuel pressure regulators job to keep a constant fuel pressure across the injector(s) regardless of manifold pressure.

 

[K2e2vin]

Thanks man. That was really helpful. I will be boring it out then.

BTW, this isnt on a bike. Im using GSXR1000 throttle bodies mated to a D15B2 flange; so i will be using the Suzuki injectors with the fuel rail. I just wanted to make sure there was enough fuel. All of this is going on a D15B VTEC engine.