Ive finally had time to start my build but i need some help with the fuel system(as if the title didn't give that away). I have a 255 lph fuel pump, a vortech 1.1 smu, a aermotive fpr, and a set of deka 83lb injectors. I need to know if i should replace my fuel lines with either 6an or 8an braided lines or if the stock lines can handle the increased flow. Im planning on running the injectors at 55 to 60psi, and i was wondering if this is the correct pressure. I plan on running around 20 psi ,and if my math is correct my injectors should never run over 75% of there maximum duty cycle.

Heres my set-up

Built bottom end-8:8:1
ported head
crane 16s
2.4 valve train
turbonetics 60
modern performance tb
obx intake manifold
obx fuel rail

Originally posted by Raine883
Ive finally had time to start my build but i need some help with the fuel system(as if the title didn't give that away). I have a 255 lph fuel pump, a vortech 1.1 smu, a aermotive fpr, and a set of deka 83lb injectors. I need to know if i should replace my fuel lines with either 6an or 8an braided lines or if the stock lines can handle the increased flow. Im planning on running the injectors at 55 to 60psi, and i was wondering if this is the correct pressure. I plan on running around 20 psi ,and if my math is correct my injectors should never run over 75% of there maximum duty cycle. Heres my set-up Built bottom end-8:8:1 ported head crane 16s 2.4 valve train turbonetics 60 modern performance tb obx intake manifold obx fuel rail

I upgraded my stock supply line with 6an. I got only 1 fitting on and its a 90 going into the adapter for the rail.. The rest is just push on. Didnt take very long. good upgrade

what do you mean push on? can you be more specific?
some pics would be nice!

I believe he is refereing to push lock fittings.

Out of curiosity could i just ditch the fmu since im using an aeromotive rising rate regulator? It seems unnecessary for me too use both.

I was wondering why you had both myself when reading your first post.

Originally posted by Raine883
Out of curiosity could i just ditch the fmu since im using an aeromotive rising rate regulator? It seems unnecessary for me too use both.

Then why did you buy both?

Your order should be: pump->rail->fpr->tank. If I recall the aeromotive comes with instructions on its placement. Why did you not read that? And in the chance you never got one, why did you not call them or check their website?

The stock 5/16 supply line is sufficient. Or use it as a return line and run a new -6 or 3/8" as a supply.

This has been covered extensively. Search, as usual.

I didnt buy both my donor car came with the fmu. Ive searched both the wiki and past threads and i cant find any direct answers as to whether or not the stock fuel line would be sufficient for injectors as large as mine. All i need to know is if im correct in using -6 and -8 an, and if that if 55-60 psi is the correct setting at idle. Im not familiar with sfmu units but from what research ive done they seem to be a less accurate rising rate regulator.

There is no correct fuel pressure. Run what you want to get the flow you want. Realize that the flow characteristics for your injectors are rated at a certain PSI.

Additionally, look at the flow of a 5/16" line. Then calculate how much fuel you are going to be injecting through 4 injectors at your theorized maximum pressure and duty cycle. Compare the two. This is all basic stuff man.