sbc 400 casting, which is best?

[Brian79]

I know that the 2 bolt is stronger than the 4 bolt but not sure which casting is stronger? Going to a swap meet this weekend and would like to know what to look for as in best to worst. Which ones are good,ok, and stay away from. Also how do I tell if it is a 400 vs 350 and so on? Going to use it as drag motor only no street time.

 

[chevy406]

509 casting are suppose to be the best, im no block expert but i know 400's have steam holes in the block, im not sure if 350's also have them, but when you order head gaskets for a 400 it comes with the steam holes and the 350 gasket doesnt, id look for the steam holes in the block between the cylinders. good luck

 

[TNTS79]

My 4 bolt main 400 block has 3 freeze plugs per bank, thats one thing to look for. Steam holes will only be on the 400 blocks, 509's being the strongest 2 bolt main blocks. Splayed maincaps on a 509 block are about the best way to go for a 400 block...

 

[Brian79]

how about ones to stay away from or are there any?

This is my plan(hope). Moderate build 12 to 1,hi 500 to low 600 lift cam,forged/balanced,maybe stroked and whatever N2O it take to get the car running low 10's/hi 9's. Will any 400 block handle this load?

 

[bowtie81]

stay away from the 511 and any of the 4 bolt 400's. as said before try and get the 509 or 817.

 

[ProJunk]

stay away from the 511 and any of the 4 bolt 400's. as said before try and get the 509 or 817.

X2. The 509 2-bolt block with only TWO freeze plugs per side is the strongest of 400 castings.

As for your goals, for longevity of the block and rotating assembly I would recommend doing several things with the block:

1) Fill the water jackets with a good quality block filler to the bottom of the water pump holes.

2) Install nodular iron or billet steel splayed 4-bolt main caps on the center three main journals.

3) Use main & head studs.

4) Stick with a 3.750" stroke. If you run a 3.875" or 4.000" stroke then you will have to clearance the inside of the block quite a bit. While this is a standard operation, it's very time consuming and removing material from the block isn't going to do anything positive for strength. You can easily reach your goals with a 3.750" stroke engine.

5) Stick with a 5.700" connecting rod. If you plan on spraying the engine, you'll get a stronger piston with a better ring package for nitrous use with the 5.700" rod vs. a 6.000" rod.

6) Keep in mind that by the time you find a good useable block, buy the main caps, and pay for all the machine work, you're probably going to have anywhere from $900-$1,200 invested in the block. At that point, you're not that far away from buying a Dart block which already has everything you could want and more. Even the new Dart SHP block would be up to the task for your goals.

 

[chevy406]

ive got a spare block here at the house, it has 330817 stamped on the back side of it does that mean its a 817 block?

 

[art]

stay away from the 511 and any of the 4 bolt 400's. as said before try and get the 509 or 817.

X2. The 509 2-bolt block with only TWO freeze plugs per side is the strongest of 400 castings.

As for your goals, for longevity of the block and rotating assembly I would recommend doing several things with the block:

1) Fill the water jackets with a good quality block filler to the bottom of the water pump holes.

2) Install nodular iron or billet steel splayed 4-bolt main caps on the center three main journals.

3) Use main & head studs.

4) Stick with a 3.750" stroke. If you run a 3.875" or 4.000" stroke then you will have to clearance the inside of the block quite a bit. While this is a standard operation, it's very time consuming and removing material from the block isn't going to do anything positive for strength. You can easily reach your goals with a 3.750" stroke engine.

5) Stick with a 5.700" connecting rod. If you plan on spraying the engine, you'll get a stronger piston with a better ring package for nitrous use with the 5.700" rod vs. a 6.000" rod.

6) Keep in mind that by the time you find a good useable block, buy the main caps, and pay for all the machine work, you're probably going to have anywhere from $900-$1,200 invested in the block. At that point, you're not that far away from buying a Dart block which already has everything you could want and more. Even the new Dart SHP block would be up to the task for your goals.

Not to thread jack, but isn't a 400 rod a couple thousanths shorter ctc than a typical sbc rod? (5.65 vs 5.7)
I agree with the recomondation of the SHP Dart block. From what I read in the new Car Craft, unless you do all your own machining, for the money, you would probably be better off with the SHP.

 

[grizwald]

ive got a spare block here at the house, it has 330817 stamped on the back side of it does that mean its a 817 block?

where do you find the stamping numbers? i'd be curious to know what block i have in my car.

 

[chevy406]

its was on the back side of the block, were you bolt it to the transmission.