I have a OBDI JDM B18C(10.4CR/9.4with head gasket) in a 94 EX. My planned set up is as follows,

ERL fuel rail
ERL fuel reg.
upgrade fuel pump
ERL turbo manifold
MSD wires
MSD coil
MSD distributor
MSD box
AEM EMS
Tial 38mm external waste gate
Blitz BOV
HKS front mount
HKS turbo (comperable to a T3)
3" down pipe
Cometic head gasket
ARP head studs
skunk 2 intake manifold

I plan for about 7 psi daily and 10 at the track for now. My question is what size injectors would work best for my setup? Ive already decieded I want RC engineering, but have no clue on what size would work best for me. I would like something a little oversized for this setup, so if I do end up blowing it up I can just build the motor and boost higher.

 

Give us how much boost you plan to run, and a horsepower figure can be estimated from that, which will lead to the right injector size.

 

I am planning for 7psi daily driven and 10psi at the track. Shooting for around 330hp at the crank which estimates to around 280whp.

 

The following is guide for selecting fuel injectors corresponding to horsepower and stock fuel pressure (40psi at the fuel rail). The sizes were estimated using 90% duty cycle of the injector. The sizing of the injector is heavily dependant upon the air/fuel level the engine is tuned at (ex. 12:1 air/fuel will take more cc's than 12.5:1 air/fuel) :

310cc 200~220whp
370cc 220~280whp
440cc 280~330whp
550cc 330whp~380whp
660cc 380whp~425whp
720cc 425whp~475whp
880cc 475whp~525whp
980cc 525whp~600whp

 

Don't know for sure, but would you also be safe running with a bigger injector and then turning down the fuel???

not sure with honda applications, but with with most nissan engines that are commonly boosted stateside (sr20de-sentra/240, ka24de-altima/240, vq30-300Z/Maxima) alot of guys either run the 370cc injectors from a early 90's 300ZX or run with the MSD 50lbs units and in conjunction use a different fuel rail and FPR to get the rigth fuel amount for their engines...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AceAltima &raquo;</TD></TR><TR><TD CLASS="quote">Don't know for sure, but would you also be safe running with a bigger injector and then turning down the fuel???</TD></TR></TABLE>

Yep if your gonna buy injectors you might as well get something big since with a hondata or aem (whatever) you can always scale down the injection usage.

Depending on the injectors too, sometimes the hondata has problems running lean enough with huuggeee injectors. 750cc are nice though on a street car.

math for finding the right fuel injectors
http://www.rceng.com/technical.htm

liam