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Oct 25, 2007 | 04:59 PM

1Fast7R

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From: Huron OH

For you engine builders out there ?

If i build a 400 small block should i go with the 400 mains or should i go with 350 mains? The crank will be a 4" stroke with 6" rods. Now from what i have heard some like to use 350 main size for less friction. Is this true? Also it will be a 2 bolt with a 4 bolt slayed mains and maybe a girdle also.

Oct 25, 2007 | 06:03 PM

jeffyc

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are you "stroking" a 350 block out to a 400? (4 inch stroke)?

or using a 400 block?

if your using a 400 block u should use the 400 main bearings.

Oct 25, 2007 | 06:15 PM

1Fast7R

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From: Huron OH

I am useing a 400 (a 434 when done) sbc. By useing the smaller mains dose it make it weaker in any way?

Oct 25, 2007 | 07:11 PM

CFI-EFI

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From: The Top of Utah

So you have a 2 bolt, 400 CID block into which you are going to have splayed caps installed. You want to know whether to use a crank with 350 mains and spacer bearings or spacers for 350 bearings, or a crank with 400 mains? Since the block already has the 400 main saddles, I say stay away from spacers or spacer bearings.

RACE ON!!!

Oct 25, 2007 | 09:15 PM

Deakins

Burning Brakes

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From: Iowa

400 mains is the only way to go! Also, is this block a tall deck or are you going to use a super short piston? Back when I looked they were very limited in selection.

Oct 25, 2007 | 09:26 PM

cv67

Team Owner

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From: altered state

St. Jude Donor '05

Sounds like GM pass car block.

Oct 26, 2007 | 03:18 PM

1Fast7R

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From: Huron OH

It is a gm block. I also have a question on crank lightening. Is it ok for the street and how light should it be? I have seen most at around 40lbs and some as light as 35lbs. The stocker is 54-57lbs.

Oct 26, 2007 | 03:47 PM

T. Wayne Nelson

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From: Eden Utah

400ci

I used a Scat 4340 crank and rods on mine. Went with 400 mains,
1 400 ci block
2. Line honed, bored .30 to 406 ci
3. Deck squared
4. Scat 4340 crank – polished
5. Scat 4340 rods
6. Speed Pro hypereutectic pistons
7. Engine internally balanced and blueprinted

The rods were 5.7, had the wrist pins set up in the piston to end up with a 11/1 compression ratio.