Help upgrading fuel system

I did a search and went through 6-7 pages of bs, so now i’m posting this up. I’m building a b18c1. Here are the stats as of now

b18c1 block and head (head has been P&P)
USDM .25 over ITR pistons
crower valvetrain/402 cams
bored tb
skunk2 IM
DC 4-2-1 (for my LS)
Greddy sp exhaust

compression ratio with the head work and pistons should be right around 11:1. My fuel system is completely stock. What do I need to do as far as fuel is concerned (besides running 91 octane) to make this as safe as possible? I’m currently trying to decide to go with hondata or something like a AFC. I’d like oppinions on this too, but mostly I want info on injector size, fuel pump, fpr, etc…


Hondata vs. V-AFC is not even a comparison. If you have the money, grab the Hondata. The Apex-i unit is a band aid, and allows for only a coarse correction in fuel, and nothing for timing.

I’d at least grab a FPR for now. I ran 11.3:1 with stock injectors and a B&M set at 45psi with no issues at all. If you plan on running very high fuel pressures, I’d grab a fuel pump as well, as high fuel pressure make the pump wokr harder and actually flow less fuel as pressure at the rail increases. Go look around at hondata’s site, they have a lot of good info in pumps, injectors, and tuning, as well as

I would go no larger than 270cc injectors with that setup. If you get ahold of the hondata, put it on the dyno, and check injector duty cycle to see where you are at. Honda’s typically run about 85% duty cycle on stock motors, so you will start to creep into the range where they cannot keep up with a fairly built motor. High duty cycles increase heat in the injectors make they less accurate, as well as them having to fire more often and stay open longer to deliver the right amount of fuel. I currently run 12.1:1 CR with a set of 290cc H22a injectors and a B&m regulator set at 50 psi with no vaccum. I have yet to get on the dyno yet and check EGT’s and A/F ratio with a wide band, and I am waiting on the Hondata Stage 4 to show up, so I can give any info on that setup other than it runs leans even with the 290’s…

Damn Daniel… u got the Hondata coming huh? sweet. remember us Californians only have 91 oct here… sucks ass. well im going for the 310s on my set up… with the “band aid” heheh… yah i know… u don;t like it… and at this point i just wanna get up and running… if i get 200whp i’ll be happy… but a high tq number is what im gunning for… 140 baby :wink: IMO joe if u can get the hondata get it. and 270s w/ a adj/ FPR sound right to me as well.

Sorry to bring back such an old post, but i figure less flames than asking the same question twice. Well I have now decided I will be squezing on this motor and still haven’t bought injectors or a fuel pump. I don’t know when I’m going to get to the bottle but do you guys think I should get 270’s now and switch them out for bigger ones later, or get larger ones now. I will be running a small shot like 50-75. I decided it should be pretty safe to squeze since I got forged pistons/rods going into my motor now.