Is there somewhere that can tell me if 550cc seimens injectors can support 300 to 325 rwhp and at what duty cycles? What lb's/hour would these convert to? I come up with 52.38#. is this correct?

 

Check out this site: RC Engineering

 

There are also dozens of calculators on the net, just google it. One guy on here reckons he gets 480+WHP on his 55's. I dont believe it can flow or "safely" flow that myself.

 

I must be doing something wrong with these calculations!!! I'm running 3 bar rail pressure. with the intent of a maximum 500hp at the crank (about 23-25psi I think) from 4 clyinders. The website suggests I need 93lb/hr injectors to run at 80% efficiency!!! Not good because I was only fitting 55lb/hr!!

Ben

 

I have seen those calculators before. They all say I need 75 to 90 lb injectors. I know people run 52 to 55# injectors for around 360 at the crank which is what i am shooting for ( 300 to 320 at he wheels).

 

I entered crank hp = 370
4 injectors
bs fuel = 065

max duty cycle = .80

fuel rail at 44 psi( is this correct?)

It comes up with 74lb injectors. What gives?

 

I'v just been very relaibly informed that the calculations are wrong. Andrew Sweetenham who used to own a very nice example 2.8lt 944 turbo with 422hp at the crank. He was running 55lb/hr injectors and told me they had plenty of capacity spare. I would trust his opinion and use 55lb/hr.

Ben

 

I just found out that the injectors I had been looking at are 3102 injectors. I have seen these listed for sale as being 55 lb injectors so I may be ok.