400 small block chevy

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daharh
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400 small block chevy

Postby daharh » Wed Sep 28, 2005 5:47 am

i am about to build a 406 chevy I like the idea of having high torque and horsepower in a small block format however heard there is a possibility of running a little hot in a airboat application ? does anyone run a 400 are you happy with it and have you ever had heating problems thanks for your help COPPERHEAD

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Waterthunder
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Postby Waterthunder » Wed Sep 28, 2005 8:03 am

Cool a 406 my favorite, good choice. I Have built a lot of 400 SBC for airboats you only need to do a few simple things to the cooling system and you will never have a problem. I have several that have 5 plus years of service without a single problem even in guide boats. What size boat are you running and what HP range are you building. If your interested I could tell you a few tips in the short block that make a huge power difference in an airboat motor.

daharh
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Location: ontario canada

Postby daharh » Wed Sep 28, 2005 10:37 am

I AM USING THE PARTS FROM MY 350 I TOOK THE REAR MAIN OUT OF IT THE LOCK WASHERS IN THE RING GEAR SPLIT AND THE BOLTS WORKED LOOSE AND WEDGED IN BETWEEN IT AND THE FLEX PLATE OF THE 2.3 REDUCTION GEAR PUSHED THE CRANK FORWARD AND GUESS WHAT NO MORE MOTOR.GOING TO USE MY ALUM VORTEC HEADS AND CAM GETTING NEW CRANK PISTONS AND RODS BUT READ BY GOING TO THE 406 I GAIN BIG BLOCK POWER IN A SMALL BLOCK FORM

daharh
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Location: ontario canada

Postby daharh » Wed Sep 28, 2005 10:55 am

JUST A LITTLE ADD ON TO MY REPLY A RACE CAR DRIVER UP HERE SAID THEY HAVE THE SAME PROBLEM WITH STAR WASHERS IN THE FLEX PLATE RIPING APART AND NOW THEY PUT IN SPECIAL BOLTS NO STAR WASHERS AND LOCKTIGHT THEM IN AND NO MORE PROBLEM JUST FOUND OUT A LITTLE LATE AFTER I DESTROYED AN ENGINE HOPE THIS MIGHT HELP SOMEONE AVOID SAME PROBLEM

barhopper
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Postby barhopper » Wed Sep 28, 2005 9:17 pm

I've been running a 400 for over 8 years and have had no problems (knock on wood) at all. I run a high volume water pump and a aluminum radiator. At idle it doesn't get above 150 degrees and only about 170 degrees when running hard with a 2 to 1 belt box.

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Waterthunder
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Postby Waterthunder » Thu Sep 29, 2005 8:15 am

Sweet your set it up is dead on the money. I argue water temps allot and people think I run my motors too cold. Well for max power I do (AND EVERYBODY KNOW V/8’S MAKE MAX POWER AT 180) however I'm willing to loose 10HP and make it up somewhere else in exchange for years and years of reliability. That's funny you run in the exact water temp range that I have found to be the most reliable for an airboat. I'm sure your 406 does everything you want and is dead reliable.

Keeth1123
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Re: 400 small block chevy

Postby Keeth1123 » Wed Jan 23, 2019 9:21 am

Is it bad to run it cold? I was only running 150-160 temp wise the other day because it was cold out
:old_glory:


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