I have a 6.0 with a 6012 box a 750 hp

Cold it shuts right off

Hot it will run on unless you let the car idle for 30 seconds.

I have not touched the timing just pluged pill 4 in and drove it.

Anyone else run into this. Idle is in the 900 rpm range

Tim

I have had "run on" before, when i had the idle timing too low, and the throttle blades open too far to achieve the idle speed I wanted. I cured it by increasing the timing at idle speed , and then closing the throttle blades to get back to the idle rpm I wanted.
I have mine set at 20* from 0-500rpm, then ramping quickly up to total timing(32*) by 700rpm. my high overlap cam and 9.6:1 compression really like alot of timing at idle and up toward 3500.
HTH

Thanks

Kind of what I thought I have not even plugged the laptop in to see where things are at with this pill. Once the car is out of the body shop next week I am going to jump on the little issues like this

Thanks
Tim

While retarded timing and poor fuel quality exacerbates the problem, what causes "engine run on" after the ignition is turned off is typically carbon deposits in the combustion chamber. The carbon gets hot and acts like a glow plug in a diesel engine creating an alternative ignition source for the air/fuel mixture.

The engine is brand new. The carb is very lean other than WOT. I had the plugs out of it yesterday and they looked like I just took them out of the box.

It is the timing and idle. I just have not had time to mess with it.

Tim

How much compression?

Stock L76. 9.4 I think.

My 6.0 does the run on too. My pistons are sparkley clean with brand new heads. If i rev it up then shut it off without letting it idle for a few seconds it will "run on". If i let it idle for ten seconds it will be fine.

No wonder I have #6 pill in
0 4
1000 8
2000 24
3500 25
5000 20
6000 23

It will run just not real good

Should be able to fix it with just a quick change

Tim

In my humble opinion, it will never run right with any of the pills that come with the 6012. If you can believe the specs they show, none of them have enough advance at 800 RPM for any kind of cam, even a mild one and none have any advance at higher RPM either. None have over 23-24*. You need a laptop.

^X2

Not sure about the MSD6012 box, but my 6010 had all the chips set at a 5500rpm rev limiter. My engine would hit 5500 before I could bat an eye and stay on the limiter until I lifted the throttle. The chips supplied with my 6010 also had a very high total timing at like 36 degrees which is way too much for an LS engine. So be careful if you have pills like that. I only used the pills to fire the engine and then formatted the timing curve with the supplied software via laptop. My MSD6010 came with an old 9-pin computer connector so I had to go buy an adapter at radio shack. After I sorted all that out, it was easy to set up a curve.

I think both the 6010 and 6012 come with the RPM limiter set at 5500RPM. Don't think the Edelbrock box has one. The pills for the 6010 have timing curves that will work in a lot of engines and if you look at the specs for them in the instructions, they are completely different from the ones supplied for the 6012. As for the 36* total on most of the 6010 pills, there are a lot of guys on here with cathedral port heads running that much total advance.

Got down to the shop today loaded a tune with some timng at idle and dead cold it fired up and idled without touching the throttle.

Didn't get to warm it up and check for run on but I am confident it will fix the issue.

Should be able to get the car out tomorrow and do some driving with it.

With the min and max timing where do you set that at

Don't see any reason it should be higher that what the table is set to go to.

Tim

I set mine at the max timing it will see with vacuum advance + total, at my cruise rpm. the min I set to 0

I wonder if these boxes for LS engines have the same problems that MSD 6's have with backfeed from the alt. You need a diode installed on the alt brown wire(exciter).
Aleck

Well I got the car out and messed with it some.

Idle timing is 40 and curves down to 26 by 2500. Going to hook the map up so I can put some morein it under no load conditions down the highway and see what kind of MPG we can get out of it.

It dosn't run on any more either.

Fired up dead cold without touching the throttle. This is with 750 HP no choke horn.

The 6 degrees I added really woke this thing up need to get it on the dyno to see exactly what it is going to need.

Dad loves the 87 octain at the pump.

It will pull a 1000 rpm turn in 3rd gear with no lugging or bucking.

FTI really did a nice job with the combo as always

I have never had any alt fead back issues with any of the MSD stuff on this car or my mustang.

Tim

Good to hear. Keep the updates comin, and let us know how she runs down the 1320

I don't expect to ever race this car. It will see the dyno just to see what we can make with it. My dad will drive it everyday this summer.

Wish I could stick the slush box and radials off my car on this car I am sure it would be quick for what it is.

Tim