I'm finally to the point where I think it's time to try to fire the motor with the Accel DFI. Anyone gone through an initial fire with the EFI that has some tips on what procedures to use?

Thanks - Greg

 

No exp with a vette EFI but have done it with a Ford.
All I did was recheck my work, turned the ignition on and tried to start it. Had a fire extinguisher handy. Good luck

 

I got my sb427 with the FAST xfi setup started with a basemap that was way too rich with the intention of tuning it after I got it started. I eventually took it to a guy that did a quick dyno tune. Anyway, of course the plugs got replaced twice in the process and the wide-band sensor was doused too, took quite a bit of run time before it started reading close to the tuner's sensor. Was off by 2.5 A/F ratio for awhile, eventually got it down to .5.

 

Hey

I have been doing a lot of work with EFI during the last many years (mostly imports with big turbos) and this is the procedure I normally follow:

1. First, pick a basemap that suits your engine built in the best way.

2. Check and recheck that all components are installed as outlined in the install manual.

3. Then turn on ignition and go into your software and upload the basemap you have picked, then make sure that you have all the sensor inputs reading correctly, IAT, TPS etc. At the same time you can adjust the TPS if needed. When doing this, make sure the fuel pump circuit is off.

4. Turn off ignition, remove spark plugs, reconnect fuel system and prepare to check that all fuel lines are dry. Reason to remove spark plugs is to make sure that you do not have a leaking injector (Vapor lock). Then switch the ignition on and off a few times to make sure your fuel system is fully primed. Check all fuel lines for leaks and turn the engine by hand to make sure no fuel is coming out of spark plug holes. I have seen so many new quality brand injectors leaking new out of the box so be sure to follow this step.

5. Put everything together if the test went smooth and now it is time to verify that you have sparks at the spark plugs. If so, you are now about to start the engine for the first time.

6. What I normally do just prior to start if I have a wideband is to make sure that the EFI computer is in closed loop and hooked up to the wideband. At the same time adjust range of the closed loop correction to maximum and make sure that the closed loop temperature is set so low that it will apply corrections all the time after start. Set the target AFR to around 14.7 (Stoic) If you have an idea of what vacuum your engine will have at idle you can scale all your different maps accordingly. This way it will not run too rich/lean and I can then adjust the base fuelmap so the closed loop is reading around -3% to -5% when engine is warm.

7. You can now cross your fingers and start the engine for the first time. When running, check all inputs yet again to make sure everything works ok. Then you have to synchronize ignition and the basic tuning can begin.

As a matter of fact I do have the Gen. 7 ACCEL DFI for my own 407 small block and I will start the install shortly.

Good luck and regards from Denmark

Karsten

 

Thanks for the tips. The base map was generated and loaded by the shop that did the EFI conversion of the Hilborn 8-stack intake. I need to get a USB to RS232 converter before I can hook my laptop to the computer since the Calmap hookup is for RS232 and my laptop doesn't have any of those ports, only USB. I hope none of the injectors are bad since they need to be custom marchined (threaded) to use in the manifold.

I'm planning to have it tuned on the chassis dyno, but that has to wait for a driveshaft.

-Greg.