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Author Topic:   400 350 blocks
Dirt Full Roller

Total posts: 57
posted August 03, 2005 06:33 PM  
how can tou tell a 350 from a 400. can u do anything to make a 400 pass for a 350.

Dirt Full Roller

Total posts: 50
posted August 03, 2005 07:41 PM  
on a 400 block you can feel the cylinders from the outside of block and you can see them also

Dirt Maniac

Total posts: 116
posted August 03, 2005 08:28 PM  
last 3 numbers of the 3 400 castings are 817,509 and 511. The first two are two bolt mains, and the third is a 4-bolt.

Dirt Maniac

Total posts: 176
posted August 03, 2005 09:37 PM  
OMG....are you thinking of cheating? lol j/k. From what I see you'd have a hard time to disguise a 400 as a 350 because you'd have to change the casting #'s on the back of the block on the drivers side behind the head. From my 16 years of racing....thats the first place the tech guys check.....kinda hard to change something thats casted into the block.

Dirt Full Roller

Total posts: 54
posted August 04, 2005 05:16 PM  
It might be hard but its been done before seen it with my own two eyes

Dirt Freak

Total posts: 300
posted August 04, 2005 09:25 PM  
Brez uses lead to put the numbers back on and if you looked closely you could tell.

As for the 400 block hiding you can grind the sides of a 2 freeze plug block flat, and change the numbers on the back of the block, at least one local machinest here does the numbers, I saw a block he did for a 377 in a hobby stock!!

Dirt Maniac

Total posts: 120
posted August 05, 2005 11:02 AM  
Just suppose you did disguise your 400 to appear to be a 350. Still leaves one huge problem. How will you hide the extra cubic inches from the pump? If anyone has the answer to that, we would love to know it.

Dirt Forum Champ
Total posts: 578
posted August 05, 2005 02:17 PM  
that depends on if you class had a cube limit or not. like the imca stockcars after 400 blocks but no cube limit either. so whats the point of a cube check then??


Dirt Full Roller

Total posts: 51
posted August 08, 2005 06:49 PM  
I have been told that a great way to find low end torque is to take a 307 block and install a 400 crank should pump like 355 with a 30 over bore. but you still have the problem to hide the block numbers.

Dirt Roller

Total posts: 21
posted August 10, 2005 03:00 PM  
why don't you just run a 383 stroker. all you have to do is get the 400 crank mains ground down to fit the 350 and do some grinding on the front to make the 350 harmonic balancer fit. the 383 will run cooler also. just a thought.

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