[Tortuga]

Spent months looking for a white GSX 5 speed, finally found one and it's currently being transported from Idaho to Texas! So as far as mods go it has:

Punishment Racing FMIC
CX Racing radiator
FP Cast turbo manifold
Custom TD-05 20G
Kinugawa internal wastegate
3" exhaust

Previous owner stated the boost is at stock levels, i'll be getting a few dyno runs in to see how shes running and what I can safely turn the boost up to without needing additional fuel mods. I keep hearing 14 psi is the sweet safe number. My question is, is turning the boost up as simple as replacing the spring or will I need some sort of controller? Also what psi could I expect to be able to increase to without fuel cut off?

Pictures and dyno baselines soon to come!

 

[Tortuga]

Also will some sort of tuning device be necessary or for now I can bump the boost without getting too serious or risking pre mature engine damage, thanks for any input!

 

[diambo4life]

I would not turn the boost up without being able to determine what the air fuel ratio is at WOT and what your fuel capacity is (injector duty cycle.) The first thing I would do is rewire the fuel pump to give it more voltage and if you can, bump up the base fuel pressure to 43psi. This should give you some head room to run more boost but you still need a wideband to be safe. With that 20G, you will be hitting fuel cut pretty soon. You definitely need to invest in a tuning device and/or chipped ECU. Hope that helps.

 

[Tortuga]

Thanks for your reply, okay I will get an AFR gauge first and also probably an aftermarket boost gauge while I’m at it. How can I determine my fuel duty cycle? Also how can I accomplish raising the pressure to 43psi?

 

[diambo4life]

Duty cycle can be determined by logging it. Fuel base pressure is achieved by adjusting the AFPR (=Adjustable Fuel Pressure Regulator) which should have a gauge installed.

Check out this section. FAQ Locator Fuel and pay attention to this section.