Motor is a JDM ITR with Skunk2 Stage 1 cams and stock 290cc injectors. I am currently running 60 psi because my stock injectors were maxing their duty cycle when I was running at 50 psi. Motor was tuned by Steve Sakai (sgt) using Hondata.

Would it be to my advantage to get bigger injectors so that I can run my fuel pressure a bit lower? What is the optimal fuel pressure for tuning

 

I believe all stock Honda B-series injectors are 230cc.

-RC designs their injectors to have optimal spray pattern at 42 psi. But I have always seen better results on the dyno with higher fuel pressure (50-52psi) and removing fuel on the graph were necessary.

Essentially I think high fuel pressure delivers a better spray pattern and better atomization to a point. Once fuel pressure get to silly amounts like 58+ just to compensate for lack of injector it is time for bigger injectors.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by asubennett &raquo;</TD></TR><TR><TD CLASS="quote">I believe all stock Honda B-series injectors are 230cc.

-RC designs their injectors to have optimal spray pattern at 42 psi. But I have always seen better results on the dyno with higher fuel pressure (50-52psi) and removing fuel on the graph were necessary.

Essentially I think high fuel pressure delivers a better spray pattern and better atomization to a point. Once fuel pressure get to silly amounts like 58+ just to compensate for lack of injector it is time for bigger injectors.</TD></TR></TABLE>

Thanks for the informative post. Most stock honda b-series injectors are 240cc but the 98+ JDM ITR injectors are 290cc.

Where did you find that RC injectors have optimal spray pattern at 42 psi? Is that on their website?

I think that is is time for bigger injectors.

 

wow, really? I never knew they increased the CC's for the 98 up JDM ITR's. Actually when I ordered a set of 370cc injectors they come with a sheet that shows the accuracy of their flow. RC designs their injectors to flow the advertised numbers at 42psi of fuel pressure. It may be on their web site as well.

 

55 PSI is the ideal number for fuel atmization

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by civic-4-ges &raquo;</TD></TR><TR><TD CLASS="quote">55 PSI is the ideal number for fuel atmization</TD></TR></TABLE>

Is this from experience? Theory?

 

Theory and fact!

 

Just keep bumping up fuel pressure on the dyno and removing fuel to maintain the same air/fuel ration until increased fuel pressure stops making power.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by civic-4-ges &raquo;</TD></TR><TR><TD CLASS="quote">Theory and fact!</TD></TR></TABLE>

I am sorry, but I would not believe any quoted "optimum" fuel pressure unless it was coming from the manufacturer and for that specific model fuel injector only. First all you have to consider the dependacies of spray pattern, and fuel pressure is only 1 of the factors. Optimum fuel pressure for one 240cc injector will be different from the next 240cc injector due to injector design and variances.

But by all means though, please post up the factual information, so that we can understand exactly what you are basing your claims on.