Author: desmodave

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.

Gen V Supercharged LT4 final hydraulic pump bracket design


Final design for bracket showing Detroit Speed banjo fitting on the pump.
Back side of the final design showing added ribbing and accessory bracket that mounts up against the block.
Update 06/07/16 – Just got word the the Factory SEMA 1970 Camaro on tour with the Hot Rod Power Tour will be carrying 5 extra pumps because the seals are failing under load.  They plan on changing out the pumps every night because they can’t get more than 500 miles on them before they fail.  Please note that the factory designed bracket does not provide support by tying into the block like ours does.  The factory built the 8 rib pulley by slicing two 6 spline pulleys apart, machining them down to the right size and them welding them back together to get the right width for the supercharger belt.  For a power steering pump bracket for the LT1 engine please click on this link

Gen V LT4 Camaro hydraulic power steering pump

Here’s the first design for the hydraulic power steering addition to the serpentine supercharger drive.  It’s mocked up with an aluminum plate, but we’ll need to add some support on the back side by triangulating a bracket on to the engine.  The reservoir sticks out a bit too much, so I’ll probably revise it with a remote unit.
Here’s the backside view showing the hydraulic connection which is a 2009-2011 Corvette power steering pump line available for less than $10.00 from

Gen V LT4 Power Steering Pump

The new generation of LT engines use electric power steering and there is no provision for hydraulic power steering.  The GM factory built a prototype 1970 Camaro for SEMA that uses a special one-off 3D printed part that accommodates a conventional pump, but that part is not available.
20160131_154719_Richtone(HDR)They used a conventional Type II pump as shown above.  Unfortunately, they run it off the supercharger drive which uses an 8 rib belt instead of a 6 rib belt.  Whatever the factory used I can’t find it because it simply doesn’t exist at this point within the GM family of off-the-shelf parts.  There are a number of websites that list 8 rib pulleys, but they come at a steep price – Innovators West is one such place.  I managed to find an 8 rib power steering pulley with a bore of .663 from a 2007 Dodge RAM Truck.  The part number is Dorman 300-149 and they run around $50.00.

Fortunately I’ve been through this drill before with these pumps and I just happened to have a 2009-2012 Corvette Power steering line ready to go.  You can see from the picture above that they have to an extremely thin threaded collar to get enough clearance to miss the pulley.  On previous LS installs I’ve done it’s much closer to the pulley.  I can still move it in a little closer, but I’ll wait until we build the mounting bracket which we’ll add to the serpentine belt system before the final adjustment.


Gen V LT4 ’68 Camaro Morrison Detroit Speed Rack and Pinion Steering

Morrison sources their steering rack from Detroit Speed because I think it’s one of the best out there.  Coming off the 2″ steering column is a 1″ DD x 3/4″ DD vibration reducing U-Joint from Borgeson.  These eliminate the unsightly and funky looking rag joint that was a staple of these mid-sixties GM cars.

Plenty of room all around with the factory hand-built SS headers and the front mounted DSI power steering rack.  This is sometimes a critical area for space depending on what type of header system you use.  This location would be where the original power steering unit for the Camaro would have resided.  Most aftermarket long-tube header systems are designed around this steering gear so there should be plenty of room depending on what type of header system you used.


Gen V LT4 Morrison Oil Cooler Conflict

You never know what’s going to happen until you drop the engine in for the first time.  The oil cooler is optional on the LT1 engine, but not on the LT4. Here you can see the interference fit with the Morrison Clip.
After removing the oil cooler you can see how it attaches and the path for the oil flow.  The back side of the oil cooler has O-rings that seal against the pan.
I have recently read that there are block off plugs for these connections but I haven’t found them yet.  I also think this a superior cooling solution for the LT4 which has a history of overheating oil issues during hard driving during track days.  There have been a lot of negative posts on this issue lately and the new 2017 Z06 and 2017 ZL1 Camaro have many new added cooling features.  I also think that by removing the oil cooler from the sump and relocating it in the front of the engine helps substantially with any potential overheating. It’s always much easier to add a larger cooler if needed.

If you look at any of the off-road buggy and Class 5 trucks, the oil coolers they run are substantial and many times are fan driven for additional capacity, they don’t use engine coolant to cool down the oil.


1968 Camaro Z06 – LT4 supercharged Gen V – 650 hp – 650 ftlbs. torque

Just showed up today (3/22/16) from Fedex ground.

Finally decided to bite the bullet and go with the LT4 instead of the LT1 (at the GM showcase at Barrett-Jackson). The most powerful stock engine that GM has ever built.



What I lovingly call the “Flat Plane Plenum”, if you look closely you can where the fuel injectors are located, halfway down the cylinder wall.  This photo shows the high-pressure fuel system.  72 psi from the tank into a mechanical fuel pump that runs off the cam, 2900+psi into the engine.

20160131_154719_Richtone(HDR) 20160131_154641_Richtone(HDR)

These are shots from the Factory’s 1970 Camaro build that I saw at the Grand National Roadster Show in Pomona, showing all the tricks they used to get things to work.

First off there is no provision for hydraulic power steering because all of the LT motors use electric power steering and there is virtually nothing on the market right now (03/19/2016) that fills this gap other than Dirty Dingo.  After spending several hours on the phone with the factory reps, they told me the prototype engineers built a 3D printed part and that’s what you see.  They used a conventional GM type 2 power steering pump and added it to the serpentine belt system using a longer micro-V belt # K080893.  If you look closely at the picture (click on it to view full size) you can just barely ready the part number.

They also seemed to have hacked up the original heater core sheet metal and replaced the front panel to get the new E92 ECU in because it appears to be much larger than the ECU for the previous LS based engines, we shall see.