fuel/spark management system

[newaccorddriver]

i finally came to a conclusion that im going to run with MS/BTM for my management setup. ive got a few questions on it though.

i only want to use megasquirt as a piggyback fuel controller, or something like that. i only want it to control fuel outputs and such while ill hook up the BTM to it and thatll take care of my timing. if i hook it up as a piggy back and disconnect all 4 of the injectors and hook them up to megasquirt, i know ill get a CEL. also, as soon as my stock map see's boost, itll give me a CEL(it makes no difference as MS has a built in map sensor which ill be using).

my question is, would the stock IACV be able to operate under my stock ECU? id like to use megasquirt, but ive got a heavy foot, and i dont really wanna push the gas pedal everytime i back up into something. id like to know if the IACV and the ECU would still be able to hold a steady idle speed if i put some load on the engine.

[A20A1]

You guys don't have a direct vaccum based idle booster diaphragm?
Say if vaccum drops under load then it'll bump up the idle by pressing on the throttle linkage.
Just connect it directly to manifold vaccum, no ecu needed.

I dunno though I haven't worked much with EFI.

My corolla has one though.

EDIT... never mind, not sure how it would work on turbo charged motor. Do you even pull a lot of vaccum at idle turbo?

[newaccorddriver]

at idle i pull around -20 vacuum.

i know that my accord will automatically bump up the idle speed when i put a bit of load on it, but im not sure if it was from the IACV or not. it might be from the dashpot diaphragm though cause thats connected to the throttle linkage.

[bobafett]

i was under the impression that the dashopt diaphram keep the cars rpm's from dropping too quickly between shifts and keeps it from dying.

if you JUST want to use mega squirt for the fuel stuff, and plan on using a btm for spark, i would just go with SAFC, you will be accomplishing the same thing, with unit that is easier to install, and easier to tune with.

[newaccorddriver]

i was under the impression that the dashopt diaphram keep the cars rpm's from dropping too quickly between shifts and keeps it from dying.

if you JUST want to use mega squirt for the fuel stuff, and plan on using a btm for spark, i would just go with SAFC, you will be accomplishing the same thing, with unit that is easier to install, and easier to tune with.

true enough

[A20A1]

I still think you could setup the diaphragm to work on just vacuum.

But if it needs more help then a solenoid hooked up to an rpm switch will bleed vacuum to the diaphragm and raise the idle when the rpm drops to a certain point... though I dunno if you can reverse the function of those rpm swithces to activate when rpm is going down instead of up.

I'm sure there are other ways to sense load and kick up the idle, but I'm working from a carb perspective though, so that usually mean no ecu involved when I want to accomplish something like you suggested. So you can see why my suggestions are the way they are.

[newaccorddriver]

the way its hooked up on the manifold is that it senses the vacuum and will increase the idle slightly. the way i see it on the manual is a bit different, but the same concept. not sure how it works as nobodys ever seen it working cause that would involve the car moving which isnt exactly safe