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Author Topic:   Block filler ??
posted August 02, 2004 04:06 PM
What's this for? I see it in gallons. Does it help keep the engine cooler?

posted August 02, 2004 04:17 PM
are you a drag racer or a circle track racer?
if im not mistaken it is to fill the block so there is less water so the temprature of the engine will rise faster, for short runs (drag racing) not circle track.

[This message has been edited by 0six (edited August 02, 2004).]

posted August 02, 2004 08:50 PM
It will also make a rock solid bottom end for a circle track guy ....that doesnt run big lap shows!!!

posted August 02, 2004 09:11 PM
Most commonly used in 400 blocks bored .040" or more in high compression applications. It reinforces the block, but also cuts the amount of cooling water in the block. Destroking a 400 to a 377 or 353 then putting in a bit of block filler (up to where the rings actually travel) won't hurt a thing. Filling the whole block (as drag racers commonly do) requires more piston-block clearance and won't last for very long without scoring a piston (couple laps for us).

Ego Racing
posted August 03, 2004 08:25 PM
Drag races use a 95%-100% fill to the top of the block, It is to make the block stronger. To me it also seems to let crankshafts last longer. We run a 50% fill in all of our oval track gas motors and have had no problems. Heat that is generated by conpression is in the top of the cylinder not on the bottom so as long as the water/collant is in the top and cools it you are in good shape. We run about 75% in our alcky motors. I have run a few Hootors cup races with the block fill in the motor and they did well, they also wear out the cylinders less as we have seen better sealing in a 1000 lap motor with it than a 500 lap motor with out it. It keeps the cylinder round and dose not allow the bottom to flex when side loaded. That keeps the cylinders in better shape and also the pistons are going to stay round longer which also lets the crank turn in a more true circle with less torsinal loading.

posted August 04, 2004 07:02 AM
Any thoughts you can share for using this stuff properly?

Gonna build a 2nd motor this winter and it will be a stk blk 400 (421 cubes) and i am considering using this stuff. Also it will be on Alky.

Ego Racing
posted August 06, 2004 10:52 AM
The Directions in the kit are good! I use HARD BLOCK brand and have never had a bad experience with it. The biggest thing to remember is you MUST have the block deck level for the filler to work correctly and fill all of the areas needed. Clean the block with soap and water, let it dry as good as you can get it then follow the directions.

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