therealnapster

Heres the question? I'm swapping out my stock injectors for DSM 450's (and resistor box). I drive a 95' civic ex w/ GReddy kit I'm still using the vortech fmu that came w/ the kit. I already up graded the rest of my fuel system, hi pressure pump, sx reg, aem rail, but I still have the original fuel rate calibration disk in the fmu. What rate fmu calibration disk should I use w/ this setup, (I will be boosting 8lbs when racing). I've heard w/450's some people use somewhere between 12:1, 10:1, or 8:1 which is right??? ANY HELP WILL BE APPRECIATED.


Setup-aside from the fuel stuff I already listed, fmax intercooler, fluidyne radiator, act clutch and flywheel, arp studs, GReddy head gasket, d16z6 bottem end w/ d16y8 head...

DLB1994

do u have a afc

snt78

I have the same FMU that came w/my greddy kit (92-95 civic) as well; do you know what rate it is? Thanks


[Modified by snt78, 3:33 AM 1/28/2002]

Guitarzann

i beleive its 12:1

therealnapster

yea I do have a afc and avcd...I still have no clue what rate I should use. Dosent anyone out there have larger injectors with a fmu?

DLB1994

like a 5:1 or 4:1 disk and just tune with the afc

dbman96

On a single cam you could probably run wiht no FMU whatsoever and be fine on 450s.

VTC_CiViC

I run 10psi with 440cc injectors with NO FMU.. with it i'd be WAAAY rich..

AutoboTxEK

No FMU what so ever?...I'm going turbo this month with my D16...and Im running stock injectors and planing to use a Vortech 12:1 FMU....now you said NO FMU..and I'm wondering...what are the smallest injectors I can use without an FMU?..I'm scared of blowing my engine up..So I'm guessing Id rather use stock injectors and an FMU than 440cc's and no FMU....any suggestions anyone..is it safe?..which is safer...

VTC_CiViC

As long as you deliver the fuel needed, both sides are "safe" in their own respects. To me, I'd rather go the low pressure/AFC route than the high pressure FMU route, seems to reason that there'd be less than can go wrong with a system operating at the normal 50psi than a system pushing 120psi of fuel through a setup that wasn't designed for such high pressures. Not to mention that big injectors let you push the enevelope farther than the stock injectors ever will

therealnapster

How do you run 10psi with no fmu? (I'm not saying I dont believe you I've just never seen it done) So when you are at full boost your fuel pressure is still the same as it was at idle? Why does your engine not blow? The afc can adjust fuel at almost any point but this adjustment is not dependent on how much boost you are running so when you are at 4,000 rpm if you are boosted or not your afc is dumping in all this fuel. You need some kind of "boost dependent" fuel system, now does anyone out there use a fmu with 450 injectors, singe cam, b-series or whatever it really will not make much of a difference in this case. (I have seen this set up so many times but no one seems to know what I am talking about)