Need help ASAP...LS2/3/L92 question

[JaySB]

So, my car is almost done, but the guys who are working on it are trying to bypass the VVT Cam on the L92 by using an LS2 timing cover. I'm not 100% sure what the issue is because I don't have all the details, but they can't get the motor to run.

Any input would be greatly appreciated since I'm supposed to pick my car up tomorrow.

[protour_chevelle]

reading on ls1tech they say that simply unplugging it and turning it off in the ecu will set the phase to neutral...

[JaySB]

Forgot to add, running it carb'd and not FI

So, the motor isn't getting spark because it's not picking up any signal from the cam....

[Shawn MacAnanny]

The way DOD works is it has two solenoids which allow oil pressure to go into 4 cylinders lifters which 'deactivate' these lifters and keep them from opening and closing the valves. This keeps them from needing fuel and also from pumping air into your exhaust giving your 02 sensors false readings.

You can just leave it unplugged as the default mode is OFF without the singnal from the ECU the solenoids remain closed. If you want to removed the heads you can just swap the lifters with LS1 lifters and all will function that way no matter what.

If your engine has DOD you will need the 6012 box as im almost positive its cam sensor is on the front of the timing covers which means its a 4x cam sensor and has a 58x reluctor wheel. I am using the 6010 box on my 68 firbeird ls1 and i couldnt be happier. No need for a distributor.

I'm assuming you are running a 6012 box here's what to check. Hook up the laptop to the MSD box and see what voltage you are getting at the box. The box wont fire with less than about 12.3 volts or so.

See if the box displays RPM through the laptop. You need about 200rpm to get the box to fire the plugs. This is very critical. Stick a jumper box on it and try.

Are your running one of the timing pills in it? It wont start without one unless you have uploaded you custom tune. Also it wont run you custom tune if you have a timing pill in the box.

[Ron S]

I've done a bunch of LS1 conversions thru the years,but I'm not familiar with the variable timing units.The original LS1 cam sensors were not required to make the engine run,spark comes from crank signal,cam sensor just told the computer if the engine was in compression or exhaust.When unplugged it made the engine start a little strange because it didn't know if it was in compression or exhaust.I'd try calling MSD if that is your controller,they are usually very helpful.Ron

[Shawn MacAnanny]

Haha im sorry some how i read VVT as DOD. Whoops

[MastMotorsports]

So, my car is almost done, but the guys who are working on it are trying to bypass the VVT Cam on the L92 by using an LS2 timing cover. I'm not 100% sure what the issue is because I don't have all the details, but they can't get the motor to run.

Any input would be greatly appreciated since I'm supposed to pick my car up tomorrow.

With the cam phaser unplugged, your camshaft is running at full advance. More information is required to get to the bottom of the entire issue though.

Hope this helps!

[JaySB]

So, after trying everything and anything under the sun. It turns out the MSD box was bad, bought a new one and she fired right up.