402 block?
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Yes , the gaskets, haeds, cams all fit. the 454 blocks were notched at
the bottom of the cylinders for the 4 inch stroke. 427, 454
has a 4.250 bore and uses a 4.370 head gasket. you can use the 4.370
gasket on the 4.155 bore 402.
the bottom of the cylinders for the 4 inch stroke. 427, 454
has a 4.250 bore and uses a 4.370 head gasket. you can use the 4.370
gasket on the 4.155 bore 402.
Last edited by Little Mouse; Jun 6, 2006 at 09:30 AM.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
BBC weighs a lot more than sbc. It takes hp & tq to move weight. Much of the other BBC stuff will fit 402 but BBC stuff usually costs more ... especially heads. Compared to 427/454 ... 396 & 402 piston choices are limited.
BBC 402 = 4.125 bore x 3.766 stroke.
sbc 400 = 4.125 bore x 3.750 stroke ... only sixteeen thousandth's less stroke than 396/402/427.
suggest ... if you're impressed with 400+ displacement ... forget the BBC 402 and build an sbc 400. Tons & tons of choices when assembling an sbc 400 ... and cheaper than equivalent BBC part.
BBC 402 = 4.125 bore x 3.766 stroke.
sbc 400 = 4.125 bore x 3.750 stroke ... only sixteeen thousandth's less stroke than 396/402/427.
suggest ... if you're impressed with 400+ displacement ... forget the BBC 402 and build an sbc 400. Tons & tons of choices when assembling an sbc 400 ... and cheaper than equivalent BBC part.
Thread Starter
Instructor
Joined: May 2006
Posts: 178
Likes: 0
From: Las Cruces NM
Originally Posted by jackson
BBC weighs a lot more than sbc. It takes hp & tq to move weight. Much of the other BBC stuff will fit 402 but BBC stuff usually costs more ... especially heads. Compared to 427/454 ... 396 & 402 piston choices are limited.
BBC 402 = 4.125 bore x 3.766 stroke.
sbc 400 = 4.125 bore x 3.750 stroke ... only sixteeen thousandth's less stroke than 396/402/427.
suggest ... if you're impressed with 400+ displacement ... forget the BBC 402 and build an sbc 400. Tons & tons of choices when assembling an sbc 400 ... and cheaper than equivalent BBC part.
BBC 402 = 4.125 bore x 3.766 stroke.
sbc 400 = 4.125 bore x 3.750 stroke ... only sixteeen thousandth's less stroke than 396/402/427.
suggest ... if you're impressed with 400+ displacement ... forget the BBC 402 and build an sbc 400. Tons & tons of choices when assembling an sbc 400 ... and cheaper than equivalent BBC part.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
The nice thing about using the 402 big block is how well big block heads
flow air. And you can use a longer rods with the 9.8 deck height. 400
small blocks have thin cylinders compaired to big blocks. its possible to
put the 4 inch stroke crank of the 454 in the 402 if you want more cubes.
flow air. And you can use a longer rods with the 9.8 deck height. 400
small blocks have thin cylinders compaired to big blocks. its possible to
put the 4 inch stroke crank of the 454 in the 402 if you want more cubes.
Last edited by Little Mouse; Jun 6, 2006 at 09:41 AM.
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Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Originally Posted by Nacho_Libre
Yeah, I'm on the fence. Always wanted a BB car, but...money is key.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
to make the 402 chevy just took the 396 block and bored it 030
to 4.155. you would have to bore it another 095 to get to 4.250.
the 4 bolt 427/454 blocks can be bored 1.25 but even then they
recomend sonic checking the block before boring them that far.
396 wont go 1.25 overbore. If you want more cubes put the 4 inch
stroke crank in it and bore the cylinder another 030 or 060 over
396
to 4.155. you would have to bore it another 095 to get to 4.250.
the 4 bolt 427/454 blocks can be bored 1.25 but even then they
recomend sonic checking the block before boring them that far.
396 wont go 1.25 overbore. If you want more cubes put the 4 inch
stroke crank in it and bore the cylinder another 030 or 060 over
396
Last edited by Little Mouse; Jun 6, 2006 at 09:56 AM.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Seems there's some confusion on 396
BBC 396 = 4.094" bore x 3.766" stroke
BBC 402 = 4.125" bore x 3.766" stroke
-edit- ... BTW, near certainty that 72 402 block has 2-bolt mains.
BBC 396 = 4.094" bore x 3.766" stroke
BBC 402 = 4.125" bore x 3.766" stroke
-edit- ... BTW, near certainty that 72 402 block has 2-bolt mains.
Last edited by jackson; Jun 6, 2006 at 10:11 AM.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Originally Posted by Little Mouse
Ok anyway if you bore a 396 060 to 4.155 and use a 4 inch 454 crank you end up with 433 cubes.
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
I respectfully disagree with comparisons of a SB-400 to a small BB.
A BB-396 or a 402 will smoke a SB 400 if they are cammed and built with similar specs. The heads are the difference. Large SB heads have 220cc runners,..mid-sized BB heads have 290cc (O-ports),..or you could even go bigger (square ports) if you're building a real snotty 402.
And if you used aluminum heads and intake on the BB, she'd weigh only a fraction more than an iron SB.
If cost of the builds aren't too far apart, go BB.
A BB-396 or a 402 will smoke a SB 400 if they are cammed and built with similar specs. The heads are the difference. Large SB heads have 220cc runners,..mid-sized BB heads have 290cc (O-ports),..or you could even go bigger (square ports) if you're building a real snotty 402.
And if you used aluminum heads and intake on the BB, she'd weigh only a fraction more than an iron SB.
If cost of the builds aren't too far apart, go BB.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
I was thinking of bringing up that point 73 454 the small BB
will make more torque and HP then a 400 even without the
4 inch stroke crank. If I were doing it I would just use the
3.76 crank.
will make more torque and HP then a 400 even without the
4 inch stroke crank. If I were doing it I would just use the
3.76 crank.
Last edited by Little Mouse; Jun 6, 2006 at 10:52 AM.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
There's no doubt OE BBC heads have larger ports & valves than most sbc heads and have more POTENTIAL than most sbc heads. But how much of that potential is gonna be used in a budget 402 build? ... Nacho wrote "money is key". It'll take big$ for pistons if block won't go to 427/454 bore, more $ block clearancing (454 crank), sonic testing etc. And I just dunno if most 402 ... or even Nacho's 402 block can safely go another whole eighth inch (427/454)? Two-thousand dollars is kind of an arbitrary number ... but I suggest if you throw the same $2K at building either a worn-out 402 or a worn-out 400 ... a 3200 lb car would be quicker with the freshened sbc 400. Suggest the same would be true if only $1K were spent.
Thread Starter
Instructor
Joined: May 2006
Posts: 178
Likes: 0
From: Las Cruces NM
Advanced
Joined: May 2006
Posts: 72
Likes: 0
From: South Africa
Originally Posted by Nacho_Libre
