Month: June 2016

Gen V LT 4 ECM

Hold on to your hat boys, this thing is huge. Compared to the ECM (E38/67) on the LS3, the new generation ECM is more than double in size. To get this thing to fit, I cut off the back side of the heater and boxed it in. You have to use a big block heater system because the small block core coolant pipes exit in front of the back of the block.20160624_180546If you don’t want to mess with that approach, it’s best to install a Vintage Air system, throw away the old school heater core and install a blanking plate. This is what the factory did on the 1970 SEMA Camaro.20160624_183133After much deliberation I decided to drill mounting holes through the thin sides and use the existing heater box mounting bolts. Add a nut union and you’re good to go.

Gen V LT 4 Coolant temperature sensor

The LT1 and LT4 crate engines have no provision to add a coolant temperature sensor like the LS series does.  GM uses a CAN bus called GMLAN that communicates information from each of the various engine components using packet data similar to IP packets in a computer network.  Similar to a train pulling  a number of cars around in a circle, the packet data for each sensor rides in it’s own car delivering the data at the appropriate moment needed.
Unlike previous generations, the LT is the first engine in which the water pump is no longer in the center of the engine as shown above.  There is a coolant temperature sensor, as seen above on the top right, but I have been advised by GM Performance and Powertrain not to tap into the signal for fear of reliability issues within the packet data stream used by GMLAN (CAN BUS).  Since I am not using the radiator coolant to cool the oil cooler, I chose to cut off the end of the stub and plumb in a conventional coolant temperature sender.
Using a 1/4″-18 NPT tap, I threaded in a coupler and then added the sensor.  This serves two purposes, one it plugs the fluid passage and adds the sensor in a convenient location without having to weld in an additional bung.  Make sure you get the appropriate sender for the gauge manufacturer that you using because there are many different types. Also make sure you bench test the sender before installing.
water pump with sensor
Here’s the water pump reinstalled with the coolant temperature sensor pointing straight down.


Gen V LT4 Pan modification

The LT4 engine is a very tall configuration, much taller than an LS or a conventional SBC, because of this I was unsuccessful installing the engine/drivetrain combination because I couldn’t get enough angle to slip it past the crossmember because the top of the engine kept hitting the firewall.
modified pan
 also had a problem with the stock oil cooler which is bolted on to the side of the pan, this interfered with the Morrison frame (see previous post). After several very hard and forceful knocks on the pan it came free.  The LT series of engines do not use an oil pan gasket, they are sealed using GM’s engine sealant.
1st install

We decided to remove one inch from the front of the pan and then welded in AN10 oil fittings to solve the problem.  You cannot move the oil passage location because there are built in oil galleries inside that pan that connect to the oil filter.  Once the pan was modified the engine/drivetrain just barely fit it and everything settled in, on to the next challenge.
pan install

T56 Magnum Gen V LT 4 Twin plate clutch assembly

Ever wonder how a dual clutch set up works?
Here’s the 8 bolt flywheel included in GM part number 19329912, this kit is very expensive.  The flywheel is aluminum with a steel insert, the round ring concentric with the flywheel is the case saver for the bell housing.

1st clutch plate, do not use a plastic alignment tool because it provides too much clearance.
Intermediate driven plate, it’s attached to the flywheel with short flexible tangs that allow it to move and float in place.
2nd clutch plate, not sure what the small little brown cylinder objects are used for.
Completed clutch package bolted in place.
Super Magnum Bell Housing.  This guy caused me a lot of alignment problems because the tolerances appeared to be too tight.  I had to bore out the alignment pin holes to get the transmission to slide in.
Here’s your hydraulic throw-out bearing.  It’s the same one used on the LS crate motors and goes all the way back to the LS1.  Make sure you get a remote bleeder setup (Tick Performance TPSBL) because if you don’t, you’ll be cursing for days before you can get a good pedal.