JGSTURBO,

Take some time to read up on the thrust forces acting on the cylinder walls. Primarily the
Major Thrust Surface vs the Minor Thrust Surface of a V-8 Cylinder block.

Tom Vaught

 

Found some articles about major vs. minor thrust.... interesting.

When I look inside the light weight 302 casting I see a lack of structure attaching the main bearings to rest of the block. By re-enforcing this structure it should transfer SOME of the major thrust to the minor areas ?

 

That block definitely looks the part.

Let me ask you this Tom, in most applications do you think it's really necessary to build them that meaty? It seems the splayed-bolt setup has proven strong enough for just about anything short of Top Fuel, so I'm curious why the OEMs really see a need to go to the deep-skirt, cross-bolted design.

...Off to Google major vs. minor thrust surface...

 

Did not know that about the SRT 4. Good stuff.

 

The Jaguar Block is aluminum and uses a girdle, as does the Mazda I-4 Turbo engine.
The Ford 406 and 427 used cross bolted mains early on with cast-iron blocks. The Hemi Chrysler followed suit. Quote: "there's no doubt the 426 'Hemi'and RB block in general had a stronger bottom end- one well kept secret seems to be, the fuelers using 392's required a girdle across the mains and oil pan rails, otherwise the bottom of the engine would blow out and drop the crank and main caps- that was rectified with the low skirt cross bolt design of the RB/B engine"

Tom Vaught