So here it is, the answers to one of the newest big unknowns.
I personally own a A20NHT Ecotec Motor and have found a bunch of new information about it. Most of it through a minor tear down to verify parts for performing a swap that would allow me to run the current Bosch LNF ECU.
Engine Block Series Numbers will be found on the Oil Filter pod. There is a flat machined spot where the manufacture stamps all the engine data into the casting. If having a hard time reading spray the pad with parts cleaner and scrub with brass wire brush until clean, then use a brush and some paint in a dark or medium bright color and paint the entire machined pad. the paint i used is the same paint that can be found at a hobby store for painting hobby model parts. you may also be able to use touch-up car paint or a paint pen if you have those. two best colors to use would be red or black, dark green does show well too. after you apply said paint use a paper or shop towel (dry) and wipe the pad clean leaving the paint to dry in the depths of the stamped numbers/nomenclature. Take a picture and keep it for reference or spray parts clean and wipe off remaining paint to return to a completely factory state.
LNF:
86x86mm bore x stroke
9.2:1 compression
3 lobe hpfp takeoff on the intake cam
white fuel injector seals (non ethanol compatible)
sleeved cylinders
retarding intake adjuster and advancing exhaust adjuster
forged crank and rods
sodium-filled stainless steel Inconel exhaust valves
low-friction cast aluminum pistons with oil squirter's (gen 1 non adjustable)
5qrt oil system
A2NFT/A20NHT LDK (nickname Franken Blocks)
86x86mm bore x stroke
Upgraded girdle (material added here and there to prevent flex)
3 lobe hpfp takeoff on the intake cam (*still doing comparison testing to verify changes)
internal spring modification (measure higher pressure on the A20NHT spring until more are inspected not considered upgrade)
black fuel injector seals (ethanol compatible)
Non-Sleeved cylinders
retarding intake adjuster and advancing exhaust adjuster
Exhaust cam driven Vacuum Pump for Brake Booster System (may be removed and blocked off in some engine swap situations)
forged crank and rods
sodium-filled stainless steel Inconel exhaust valves
low-friction cast aluminum pistons with oil squirter's (gen 2 adjustable and from tear down measurements looks like a slight amount of material dimension changes on the underside but could be machine %error so not chalking it up to an upgrade yet)
6 qrt oil system with level sensor
LHU
Same as the LDK with the exception to new part number fuel injectors with black ethanol compatible seals. Slight pump flow modification on hpfp and ECU from Sidi with Ethanol Compatibility. (more tables for controlling blending of ethanol via use of a factory ethanol % sensor.)
As i was going through the engine replacement stages many questions arose:
1) With the new exhaust camshaft design for vacuum pump drive did they change the profiles?
A) Yes, although minute in change the cams have a slight duration timing change. at this point from only inspecting one set of camshafts i wish to not disclose the information until it can be further verified.
2) The cylinder head has been modified visually in a minor ways, did they change the oil passages to the cam phaser's?
A) No, to save money the oil passages are left in the same operation so they could utilize the same cam phaser design. The cam phaser's have gone through revisions over the years so make sure yours are up to date if you replace them on any DI Ecotec Motor.
3) Can i use the new vacuum pump assembly that is offered as an upgrade and found standard issue on the Buick Regal's?
A) Yes, if you purchase the Buick Regal brake booster vacuum line assembly you can use that with minor modification. In my case i used 1/4" ID tubing and flared the ends with a double fold to connect tubes to the t connector so i can connect the vacuum pump into the system and i utilized an crimp that puts a bulge in a short distance after the end of the tubing so when i connect the vacuum hoses it does not allow the hose clamp to just slide off the end if movement occurs.
4) Will i be able to utilize the LNF Bosch ECU? The money question of the whole post...
A) YES!!!! the crank reference wheel and the cam phaser's work the same in the LDK/LHU as the LNF. This allows a simple motor swap to take place. All the connectors for the engines sensor array and output drivers are exactly the same on the LDK/LHU as the LNF making the swap as easy as it could possibly be. On the LDK/LHU you may be the lucky owner of a deepened oil pan which takes the 5qrt LNF system capacity and raises it to a 6qrt system. If you have this oil pan you will notice a new sensors which is located on the right side of the motor on the side of the oil pan. (in easy terms it will be on the intake manifold side of the motor, located on the side of the oil pan about even to where the drain plug's location is on the opposite side)
5) Well with the new upgrades what will need calibrating and should i pre-tune any tables before i start the engine?
A) With the new upgrades and update changes in the motor you don't need to pre-tune any tables. Later down the road you may find the camshafts prefer to be located in a different position which could be a result of the profile change that hasn't been officially verified. Injector changes may be required but wont be verified until you start logging the car around town and find out the total percentage of trim skew which is simple and quick to adjust.
6) Do i need to break in the motor i just purchased and whats the recommended way?
A) Each motor is engine dyno tested at the factory to meet quality control standards but it is up to the owner if they decide that was enough break in or not. I personally recommend flashing a tune that is non-gm stage kit where you have re-calibrated for 3bar sensors and updated the turbocharger tables to match those out of the stage kit. Keep the tune as factory as possible with the exception to tuning the maf curve and base tables so your fuel trims will be on point for the new motor. Run NON-Synthetic oil in the motor for the first 500 miles or tank and a half of gas keeping an eye on oil pressure and engine temperature. afterwords perform a complete oil and filter change switching back to synthetic oil as recommended by factory. during this time you will prevent the motor from idling for long periods of time and vary the load on the engine in a range of 2200-3500 rpm. stay out of boost in pressure ranges over 8-10 psi. (in the DI Ecotec motors 10 psi is common amount of boost for climbing hills so if you live in a steep hilly area just try to limit the max boost by changing gears even if it means going over the 3500 rpm range.) unless you took the plunge and already have the GM Stage kit flash then i recommend for you to just revert to the most factory base and while driving sort out fuel trims to satisfy the new engines airflow requirements and follow the same beak-in procedure from before.
This technique helps the parts break in more efficiently by increasing the drag coefficients. With Synthetic oil the molecules are small enough to filter through the gaps and lubricate the tightest of clearances between rotating assemblies. This reduces the drag Coefficient and floats the parts over each other unlocking hp, extending parts life, and lessening the effects during the break-in process. We switch to regular Non-Synthetic oil because its molecules are bigger and don't fill into the smallest of places as well as the synthetic does. This allows the parts to have a higher friction coefficient and during the break in procedure causes a minor sanding/polishing of parts. This is most effective in properly seating the rings after assembly of a brand new engine. Reverting to regular oil for a short period of time will not hurt your motor and will allow parts to be properly seated and make for a better seal when they are pushed to the limits of our calibrating techniques.
*With that said the sanding action that takes place is not on a level you can measure via grades of sandpaper. This contact is more like a polishing effect that allows the parts to reach their final dimension and provide the best seal possible for the maximum time possible for the engines life. More info can be researched using the internet as this technique is not new to the engine building industry.
Hope this helps anyone trying to figure out what motor to purchase and what will be the benefits of each motor. As new information becomes available regarding comparisons and upgrades they will be added so feel free to share your findings with us.