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Author Topic:   383 vs 406 - how bad is overheating problem?
Dirt Freak

Total posts: 248
posted February 05, 2002 10:28 AM
I'm deciding between a Jr Motorsports 11.5:1 383 and 12.1:1 406. The motor will have World Sportman II heads so I'll lack the extra steam holes for he 406. With a mechanical fan and good aluminum radiator, how bad will the overheating problem be on the 406?

How can I get around this problem?

Dirt Full Roller

Total posts: 74
posted February 05, 2002 06:58 PM
The 406 may or may not get hot but you will have to run high octane fuel or alky if you run alky it probably will not run hot but on racing gas you will have to slow the timing down. If it does get hot get off the track or it will wash the block out between cylinders because it will probably blow a head gasket if it gets hot and blow a head gasket the compression will wash the block. It is not how much compression you have but weather or not it gets hot because my Dad had flat tops and washed the block but you will definatley need to watch the temp gauge. I doubt your 383 will run hot but in my opinion I love the 406 on its bad night it will run with the best of them.

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