Another 6.2 failure

[Marky Dissod]

The big advancement with the LS engines (carried on with the LTs) that not many talk about is that GM reversed the flow coolant. In the ole-school GM V8s the cold water from the radiator went to the engine water jacket first and then flowed up to the cylinder heads. In the LS and later engines the cold water cools the heads first, then goes down to the engines water jacket. This improved cooling to the heads making them more resistant to pre-ignition detonation and allows more compression for the same octane fuel.

Between the lower temp cylinder heads/ combustion chamber afforded by the coolant routing, and the ability to control both ignition & fuel timing, you'd think these engines would be pretty good at limiting detonation.

Gen3 Gen4 & Gen5 GM Small Block V8s are NOT reverse cooled.
The '92-'97 LT1 / L99 / LT4 are reverse cooled, but not the 'LS' or 'LT' engine families after 1997.

Coolant Flow Direction

LSx, LS1, LS2 LS7 GM Performance & Technical Information

www.ls1.com

Coolant Flow Direction - Page 2

LSx, LS1, LS2 LS7 GM Performance & Technical Information

www.ls1.com

LSx Cooling System for Dummies

www.yellowbullet.com

 

[Antonm]

Gen3 Gen4 & Gen5 GM Small Block V8s are NOT reverse cooled.
The '92-'97 LT1 / L99 / LT4 are reverse cooled, but not the 'LS' or 'LT' engine families after 1997.

Coolant Flow Direction

LSx, LS1, LS2 LS7 GM Performance & Technical Information

www.ls1.com

Coolant Flow Direction - Page 2

LSx, LS1, LS2 LS7 GM Performance & Technical Information

www.ls1.com

LSx Cooling System for Dummies

www.yellowbullet.com

I believe you are mistaken and the LS/LT are also reverse flow (meaning the heads get the cold water first, before the block). If it bothers me enough I'll pull up some diagrams of the cooling system.
...

 

[Marky Dissod]

... I'll pull up some diagrams of the cooling system.

The radiator is reverse flow (top to bottom), and the thermostat is on the inlet (not the outlet), but
those diagrams should show, like the ones I linked, that the coolant goes through the block, then the heads.