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 Mopar BB on EFI 
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Joined: Sat Jan 16, 2016 10:06 pm
Posts: 38
Lots of thanks to Rich at Fast Man EFI for the initial tune and answering a lot of questions. Finally got my 514 big block Mopar converted over to EFI. Wilson did the intake conversion, Holley supplied the EFI kit (550-501 was the base part number plus 66 lb injectors plus some misc sensors that don't come with the kit).

Here is a video of the startup. Key thing to look for is the cam sensor as well as the crank sensor. Due to the state of the aftermarket both of these parts had to be custom built.

https://www.youtube.com/watch?v=1CdKlTMNGp4


Thu May 25, 2017 12:32 pm
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Joined: Fri Feb 08, 2013 2:37 pm
Posts: 1744
Oh ... Andy ... Andy .... Gone to the dark side. Will you ever return to the land of simple physics, venturi, nozzle and jet?

Your cam sensor is a nice piece. Well done. Will you eventually install this engine in a vehicle and do some road and track testing?


Thu May 25, 2017 2:34 pm
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Joined: Sat Jan 16, 2016 10:06 pm
Posts: 38
My entire life has been one big blur of analog to digital conversions. My first job was at Tektronix where I was hired in to work on the digital scopes which were replacing the analog scopes. Then everything started to go digital, slide rules, drawings, copiers, phones, TVs, cars, etc. Now the engine controls are digital rather than analog and I'm finally accepting it. (Later on I worked at Xerox which had trouble converting from analog copiers to digital copiers and I had friends at Polaroid who all lost their jobs when they couldn't switch from chemicals to digital.) I also worked with folks from Kodak who invented digital cameras but couldn't figure out what to do with them so they stayed analog until they just about went bankrupt. So as I said, my entire life has been one big transition from analog to digital.

I will say that sitting in the dyno room with an EFI engine is a lot of fun. We dialed in a fuel curve and then tweaked it 0.1 AFR points at a time. 13.0, then 13.1 then 13.2, etc. We had one cylinder with a hot EGT so we gave it 10% more fuel. Then we adjusted the timing 1 degree at a time. Never left the control room, never shut the engine off. Just changed the fuel map and the timing map and then made another pull.

I will most likely sell off my collection of carbs and focus on EFI from now on.

I do not have a vehicle capable of handling 900 hp so no, this engine will just be a dyno mule. I do have a couple of 700 hp pump gas engines which I'm converting to EFI and one of those will most likely find its way into my '65 Coronet for some serious street duty.


Thu May 25, 2017 7:08 pm
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Joined: Sat Jan 16, 2016 10:06 pm
Posts: 38
The engine didn't make much more power on EFI than with the carb but tuning is so much faster that I think we will eventually make more power. Just because we can run a lot of tests faster and we can be more precise with the testing. Also, EFI allows me to easily dial in a fuel curve where I'm 12.8 at peak torque but 13.2 at peak power. It takes a lot of work to do that with a carb. Probably only a few guys around who can tweak a carb to do that.

What we found out in our first testing session was that WOT performance was roughly the same but it was so much easier to clean up the engine down low. With a carb it is always a chore to keep it lean down low but then go to 12.8 at WOT. Most drag race guys just give up and jet for WOT. A lot of street guys just run it extra rich all the time. With EFI we just map it out and tell the engine to be 14:1 everywhere but at WOT. We did the same with ignition and just gave it 40 degrees whenever there was some manifold vacuum. The net result of doing that was that the engine was super crisp at the start of the runs and the plugs stayed nice and clean rather than loading up. Here are a couple of pulls captured on video. I can tell the difference in the engine sound when we're loading the engine at the start of the run. It sounds a lot cleaner on EFI than it ever did with carbs.

https://www.youtube.com/watch?v=LZcFl7fy6FI


Thu May 25, 2017 7:17 pm
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