Been looking at aftermarket EFI for some time - have not pulled the trigger yet.
What made you go with Atomic over the others out there?
Plaz
My reason is in my message to another fbbo member (other info on my setup is in there as well. See below:
The system has been working great (even from the point of installation).
I am using this on a 440cu (stock) with a 727 trans (stock).
I did not do any charging system upgrades. I did make sure that the engine-to-chasis grounding was solid so I added an extra grounding line from the block to the chassis.
I did a bunch of research on the atomicefi.com web forum before I made the purchase. I had already performed an MSD electronic ignition upgrade on the car sometime before so that is why i was leaning toward the atomic system but i gave a long solid look at the holley and ezefi throttle body efi systems during my information gathering stage.
In the end i went with the Atomic as i had my questions answered by numerous users and msd tech support on the atomicefi forum and again as i had the msd ignition setup. I felt getting my questions answered ahead of time weighed heavily prior to making my purchase. The community on that forum is pretty active just like here so getting answers was pretty quick. Some of my questions on the other forums went unanswered even by the tech support staff (things may have changed since then -- i don't know).
Anyhow, after research i found that using an efi system with a single supply line and in-line fuel pump ran the risk of pump overheating (i saw this on all brands of efi systems) as well as trouble with hot starts. So, i knew going into the upgrade that i was going to run new 3/8 supply and return fuel lines (hard lines) and install an in-tank electric fuel pump. I knew adding both of those pieces to the fuel system was not going to make this a simple weekend project so i was prepared for that.
For the pump i used an tanksinc.com pa4 in-tank pump system with a summit electric fuel pump relay kit that was being triggered on by the Atomic power unit (i think that is what it is called). Since the time of my install Aeromotive came out with an in-tank fuel pump system called the Stealth 340 i think. Had the Stealth been out i may have used that one. However, there have been zero issues with my tanksinc one and it uses a Walbro pump (a very respected/reliable brand).
Since I purchased the "basic" Atomic kit i needed to purchase my own fuel pressure regulator and so i used an aeromotive one.
An oxygen sensor will need to be installed in the exhaust as well (all brands of efi need this). The basic Atomic kit will provide one.
The Atomic has the ability to control engine timing. I eventually converted the distributor to enable this feature sometime after I knew everything was working correctly. I programmed in the idle speed i wanted (750 rpm) and on start up I click the key on and the car fires right up and a second or two later the atomic controls air/fuel and timing to meet my 750 rpm and everything just purrs. No more playing with gas pedal anymore (i may miss that --- not really).
As with any system it is possible to make install errors or set up errors and have less than ideal results.
For any efi system I would add an in-tank fuel pump and a return fuel line. It may add time to the project but adds to the reliability overall.
The Atomic system works awesome and I recommend using it.
Take your time and download install instructions/parts lists and browse some of the chat forums for all brands. Thats what i did. It really gives you a heads up on any extra items you may need beforehand so you can get extra tools/parts needed. Also, i found it helpful to get install instructions printed and look at the car with instructions in hand. I could visually see where i needed to route wiring (i could see if i needed some clamps here and there) and I could see what options were available for mounting the ecu (engine bay versus interior -- this also showed me if any other mounting hardware was needed).
Take your time and plan it out.
Hope this helps.
