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Author Topic:   400 Blocks??
dirtracer14
Member
posted January 19, 2003 06:15 PM
Has anyone had good luck with the 4 bolt 400 blocks? What combo were you using with sucess and what kinda comp. Thanks


dirtracer14
Member
posted January 21, 2003 11:58 PM
Come on..........


ZIGGY
Member
posted January 22, 2003 12:50 PM
The key to the life of those is not hanging alot of gear on them. They make torque not big end hp. Keep them under 7000 and they will live.


dirtracer14
Member
posted January 22, 2003 07:59 PM
We started this with 13.5 to 1 with zero deck...didnt last so we just squared the block and dropped it to around 12to1 for some added help im going to add about 4" of block sealer to the bottom to help keep flex down and tapping intake for extra water....i just was wondering if anyone had any other secrets besides crossed fingers???


ZIGGY
Member
posted January 23, 2003 10:20 AM
The motor is pretty close to what whould be a claimer....i dont put alot of $$ in motors but i have all the parts already including machined block....but got scared of it so pulled it out after 10 laps....the crank was a new scat, srp pistons, and eagle rods so i have a little $$ in the rotating i just dont feel its enough to spend $2500 on a block by the time its ready to go. I am just tring to get what i can out of what i have, i am not putting the scat back in i went with a steel gm crank instead. I have heard tons of stories about how bad the 400 blocks are and was looking at anything i could do to help get atleast 1 year out of the motor. The other reason i didnt go with aftermarket block was the pistons are .40 over...didnt make sence to get a new block at .40 allready or spend another $700 on pistons and rings.


66jj
Member
posted January 23, 2003 04:54 PM
Are you talking about a 377??

i know plenty of guys rinning 2 bolt 400s all day long at 6800 or so, with average parts..

only thing they ever say is head studs are a must to prevent gaskets from burning thru.

ive never heard anything good whatsoever about hard block in a circle track motor.

ZIGGY
Member
posted January 23, 2003 06:24 PM
Use a good 4340 crank, balanced, and a good distributor and it'll last. Preignition will break the web on any block using any cap.Even with alky I never go over 36* timing and on a dry slick I'll pull it back to 28*...hows that for traction control?


dirtracer14
Member
posted January 23, 2003 10:42 PM
I have run the most nights on a motor with hard block in it....the mains are only 20 to 25 laps with a few 40 lappers Of wich that motor had over 30 races befor freshin. Plus running allky the motor tends to not get as hot as gas.....i have heard a guy try it on pavement(yakima) and smoked the bottom end.The last motor we did it to was all the way up to allmost the top of the block...to seal cracks from freezing... This is a 377 motor and i am gearing and caming it to keep it under 7000 and keeping the comp down as well.....and i have been saying prayers for years

Oh and if i remember right the weight of the sealer is about the same as water

ZIGGY
Member
posted January 24, 2003 07:18 AM
Ziggy
I didn't say preignition was THE reason they fail. A friend had a splayed nodular capped block with a 4340 eagle crank and broke 2 caps. He had a home made HEI and had put the weights in the distributor upside down so that it just continued to advance as rpm went up. Give me a 400 4bolt and a good USA 4340 and I'll run it until the pistons give out...been there


rico 08
Member
posted January 25, 2003 12:52 PM
400's are all smog motors(1970 on) and they almost all have core shift. 350's are cast a lot better it seems,this is why blocks fail they we're never up to par to begin with.


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