Questions about selftuning efi

[1987_chevy_]

So I have a built 383 stroker, and I am trying to figure out what to use to supply the fuel. The engine was originally built for a stock TBI system I was going to run a 454 TBI with a tune. But I have gone away from that the cam is pretty big and might not run good with the TBI and I already have a carb intake on it. The question is WILL I BE ABLE TO GET ALL THE POWER POSSIBLE OUT OF A SELF TUNING EFI SYSTEM? I've been told by the engine builder the TBI wont produce max power. If you throw a carb on it you'll gain more power.

Another question I have is the first start of a freshly rebuilt engine. will I be able to throw the self tuning EFI on the engine start it up and Rev the engine up to the recommend RPM to get the cam lubricated?

 

[SkinnyG]

EFI kicks buttox.

What matters, is just like a carb, that you get your Air Fuel Ratios correct, and your Spark Advance correct. The ECU auto tunes to those.

With a really healthy cam, you may need to tune Alpha-N, or run an Alpha-N/Speed-Density blended table to get it to work.

Look into MegaSquirt. It's really affordable, easily tuneable, and with the registered version of TunerStudio, you can get it tuned and really driveable really quickly.

Carbs do not understand air temperature, engine temperature, barometric pressure, or anything else that EFI does so very, very, well.

With EFI, I just tickity-type on the keyboard. I don't need a slew of jets, I don't need to smell like gas, and I don't even need to shut the engine off. I'll never go back.

 

[1987_chevy_]

EFI kicks buttox.

What matters, is just like a carb, that you get your Air Fuel Ratios correct, and your Spark Advance correct. The ECU auto tunes to those.

With a really healthy cam, you may need to tune Alpha-N, or run an Alpha-N/Speed-Density blended table to get it to work.

Look into MegaSquirt. It's really affordable, easily tuneable, and with the registered version of TunerStudio, you can get it tuned and really driveable really quickly.

Carbs do not understand air temperature, engine temperature, barometric pressure, or anything else that EFI does so very, very, well.

With EFI, I just tickity-type on the keyboard. I don't need a slew of jets, I don't need to smell like gas, and I don't even need to shut the engine off. I'll never go back.

Right now I am currently looking at the 600hp Self tuning EFI that summit racing sells for $995 any opinions on that EFI?

 

[SkinnyG]

No experience with that one, but a quick Google search for some install articles on forums as well as Hot Rod magazine, and it looks pretty good.

If it will allow you to fine-tune spark advance and air-fuel ratios, it would be awesome. If you can't, it will only bother you if you really wanted absolute control for every last horsepower. I'm sure it would be just fine for a decent daily driver or street machine.

 

[Tonyorlo]

Im with SkinnyG, go for Megasquirt. Ive done multiple installs with great luck. Its very simple, and there is a ton of info out there on how to do it, especially for a SBC. There is even a feature that will help you dial in your tune using a wideband O2. Once you get it in the ballpark and have it running decent it will make adjustments to be at the O2 table you set.

 

[Lu Blunt]

https://m.youtube.com/watch?v=2sQJPZYSoUI

Funny show. Good info though. Both carb and efi have pros n cons but over 4,000 rpm efi takes the cake

 

[Mattchu60]

I put a new engine in my TBI truck this spring. I went with a Dynamic EFI system. Similar concept to the Megasquirt. You send your ECM to the guy -Bob- and he rebuilds it and returns it to you. Its pretty steep learning curve but some of the things are auto-tuned for you. The system can learn the tables for the A/F in closed loop mode and get you running pretty good.

The neat thing - you can adjust a lot of things besides A/F in the system. I can control my Spark Advance timing, TC lockup settings, and other things from the laptop. My truck runs very well with a different cam (although its a mild one for towing), Iron Eagle heads, Holley TBI, removed the smog pump, the EGR removed. Doing all that with the stock TBI ECM would normally result in poor running, idling, etc, but it runs very smooth. In the words of my father, it runs like a sewing machine.

My favorite part of EFI - hitting the key on 20 degree day and it starts instantly.

I want to get a wideband O2 Sensor next year, then I can have it learn the A/F table for the entire table, including wide open throttle (open loop).

 

[Tonyorlo]

Matt,

So do you send him a stock ecm like a 747 and he modifys it? If so that would nice.

 

[Mattchu60]

Yes, you do mail to him and he sends it back after he rebuilds the ECM. I pulled mine out of the truck and mailed it to him. I probably had it back within 10 days or so. Turnaround epends on how busy he is I suppose. It was close to $400 for the package I remember.

I did not know anything about tuning before I got into it, he will help you through email (no phone) and he is pretty responsive. Also Third Gen has a ton of guys running his system, so their forums are a good place to learn about it. You need a laptop that is running windows and USB port to serial adapter (he sells one on his site that works well) to make it all go. I know another guy on here is running this system too.

I did mine with an engine install. It started it up fine, i loaded the stock file for the engine and didnt mess with it during the break in. You are going 383 route right? I went with a rebuilt 355 so its not far of stock cube wise.

Check out the Dynamic EFI site, has screen shots of the program that you run on the laptop. Also he has some good write ups on there, it took me about 5 reads of the articles before I started to even grasp it, lots of very detailed info there.