I've noticed that there are different ratios for FMUs, ie, 8:1, 12:1, 4:1, etc. I plan on running the manifold/turbo/downpipe from a Greddy 15g kit on my D16Z6 at the standard 5-5.5 (whatever) psi, and do my own fuel management, as it was only a partial used kit. What ratio should I use on the FMU? Also, should I upgrade my fuel pump if I only plan to stay between 5-7 psi?

 

Most FMUs that come with Honda turbo kits are 12:1. This is fine if you run stock injectors and low boost. The problem with FMUs is that it is a very crude and barbaric way to manage fuel. I've never seen an FMU car not run rich. Mine ran very rich with the FMU but I did not experience any major short-term problems with it. One thing to remember with a car that runs rich is that your rings won't last long, the unburnt fuel washes the oil off of the cylinder walls...

Definitely upgrade your fuel pump, the stock pump won't be able to handle the extreme back pressure for too long that the FMU causes

Good luck.

 

Rings won't last long? A week? A month? A year? Would a Greddy Blue Box or E-Manage work any better?

 

It all depends on how rich the car runs, every car is different.

Emanage is a much better way to go, but Hondata is even better.