Gen 3 LSJ Short Block


9 reviews

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Engine - Gen 3 LSJ Short Block
Engine - Gen 3 LSJ Short Block

The Gen 3 block is a huge improvement for GM and solves previous shortcomings of the Gen 1 & 2 versions of the Ecotec engine.  In fact, the Gen 3 block itself supports over 500WHP in stock form.  To make more than 400whp we would suggest better rods and pistons which are available in our Racing short block.

Improvements include:
-Cylinder wall bracing that prevents sleeves from breaking out in high HP applications
-Sand casting which removes porosity found in the older foam cast blocks
-5 pounds of additional aluminum adding internal structural support and solves the coolant jacket leakage issues with Gen 2 blocks

This is a fully assembled brand new short block, includes block, bearings, crank, DI pistons, & rings assembled as in the picture and a new oil cooler.  Does not include the water pump, timing chain assembly (guides/chain), or the front cover.  You will relocate your oil pressure sensor in the hole in the block below the oil filter housing close to the crank sensor.

Important break in procedure:

We recommend running Comp Cams "break in" oil for the first 200 miles.  Before you start the car with the new engine, we recommend that you fill with oil, then leave the injector harness unplugged and turn engine over until the oil pressure light goes out, or even better, use an oil pressure gauge.  This ensures that you are starting the engine with full oil pressure. 

When the engine is running in gear and at light throttle, bring it up to 4500rpm, then coast down to near idle(still in gear), then 5000, then 5500, then 6000, and 6500 each time letting it coast down to idle.  This will help seat the rings. Then after a couple heat cycles, start running it under power.

Freight shipping details:

Freight shipping is free for the lower 48 states.  Feel free to email for a shipping quote for a different address.

When you chose a freight shipping option, we use R&L Carriers.  Our website will email you a tracking number that you will have to enter into the "Pro Number" box on this website page:

Engine - Gen 3 LSJ Short Block
Engine - Gen 3 LSJ Short Block
Customer Reviews
5 Based on 9 Reviews
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Tommy C.
United States United States
Very impressed

I definitely felt a nice increase in power

Tommy C. verified customer review of Gen 3 LSJ Short Block
Tommy C.
Amazing customer service ......

Amazing. Very happy with ZZPerformance !! So I email like it says and boom shipping free amazing!! and it all happened fast while I was working and checking my email I’m very impressed with the results and responses from Ryan from zzp thanks again

Austin S.
I love zzp very great

I love zzp very great people very good Quality in there parts

Test T.


Guest G.
Very satisfied

I ordered a short block rocker arms and head gasket and all three came in a timely manner and whenever i had a question customer service always answered very promptly def be doing more business with you guys thank you very much