Identifying a 4-Bolt Main Block - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**Ironangel** · 10-03-2010, 12:35 PM

Is there a way to ID a 4-bolt main block without dropping the pan?

gearys 5600 · 10-03-2010, 01:54 PM

You can on a bbc engine, On a small block you really cant.
If I remember right about 80% of the casting#,s ending in 010 are 4-bolts but not all of them. Someone else might know more than me.

**GruntMoanCough** · 10-03-2010, 02:19 PM

What gearys said. Here's a bit of info that might help some if you're talking small block..... http://www.nastyz28.com/sbchevy/sblock.php

larry may · 10-03-2010, 03:50 PM

One more something I noticed all 4 bolts seem to have. Is the top center bolt hole where the bell attaches to the block . That hole is tapped with threads . 2 bolt normally is not tapped with threads.

**Ironangel** · 10-03-2010, 03:57 PM

Thanks for the replies! Its a 72 sb350 w/350tb in its org. C-10 Custom lwb. Its a factory 2bbl carb. Ill drop the pan and check her out.

cdowns · 10-03-2010, 04:53 PM

4bolts is muck ado about nothing mostly//2 bolts are fine up to 400 or so hp

Longhorn Man · 10-03-2010, 05:42 PM

yep, sell the 4 bolts for top dollar, and buy the 2 bolt blocks for a fraction of the cost.
If you wanna be a few steps ahead of the game, get a later 5.7 block with a one piece rear main seal and a roller cam.

GRX · 10-03-2010, 09:22 PM

Quote:

Originally Posted by cdowns

4bolts is muck ado about nothing mostly//2 bolts are fine up to 400 or so hp

Agreed. I have machined & built more SBC than you can shake a stick at. 4-bolts failed much as 2-bolts. Now, if the outer main bolts were splayed, then you'd have something.

po_bird · 10-04-2010, 12:00 AM

Im with grx. The only thing you get from having a 4bolt is that you can say you have a 4bolt.

10-03-2010, 12:35 PM	#1
Ironangel Senior Member Join Date: Feb 2010 Location: Falls City, Nebraska "100 Miles From Nowhere" Posts: 2,219	Identifying a 4-Bolt Main Block Is there a way to ID a 4-bolt main block without dropping the pan? __________________ Michael of the clan Hill, "Two Seventy Two's" 71 1-ton Dually 350 4-Speed 71 C/50 Grain Truck, 350 Split-Axle 4-Speed 02 3/4 ton Express 14 Indian Chief Vintage 1952 Ford 8N, "Only Ford Allowed On The Property" "Be American, Buy American"

10-03-2010, 01:54 PM	#2
gearys 5600 Registered User Join Date: Mar 2010 Location: tulsa,ok Posts: 1,085	Re: Identifying a 4-Bolt Main Block You can on a bbc engine, On a small block you really cant. If I remember right about 80% of the casting#,s ending in 010 are 4-bolts but not all of them. Someone else might know more than me. __________________ MY BUILD THREAD http://67-72chevytrucks.com/vboard/s...d.php?t=423629 1969 custom/10 swb--SOLD 1968 swb 50th anniv.--SOLD 1967 camaro ss/rs..LS-6-speed, 16-year long project 1956 chevy nomad 1955 chevy 210 2-dr sedan 1978 el-camino ss 1-owner

10-03-2010, 02:19 PM	#3
GruntMoanCough Registered User Join Date: May 2009 Location: Pemberton, BC Posts: 1,075	Re: Identifying a 4-Bolt Main Block What gearys said. Here's a bit of info that might help some if you're talking small block..... http://www.nastyz28.com/sbchevy/sblock.php __________________ My goal in life is to be as good a person as my dog already thinks I am - Unknown

10-03-2010, 03:50 PM	#4
larry may Senior Member Join Date: Jul 2005 Location: MISSOURI Posts: 3,256	Re: Identifying a 4-Bolt Main Block One more something I noticed all 4 bolts seem to have. Is the top center bolt hole where the bell attaches to the block . That hole is tapped with threads . 2 bolt normally is not tapped with threads. __________________ The biggest problem people have, is other people Thou shalt be cool and not hassle Be a site supporter. The heart of the wise inclines to the right, but the heart of the fool inclines to the left." Ecclesiastes 10:2

10-03-2010, 03:57 PM	#5
Ironangel Senior Member Join Date: Feb 2010 Location: Falls City, Nebraska "100 Miles From Nowhere" Posts: 2,219	Re: Identifying a 4-Bolt Main Block Thanks for the replies! Its a 72 sb350 w/350tb in its org. C-10 Custom lwb. Its a factory 2bbl carb. Ill drop the pan and check her out. __________________ Michael of the clan Hill, "Two Seventy Two's" 71 1-ton Dually 350 4-Speed 71 C/50 Grain Truck, 350 Split-Axle 4-Speed 02 3/4 ton Express 14 Indian Chief Vintage 1952 Ford 8N, "Only Ford Allowed On The Property" "Be American, Buy American"

10-03-2010, 04:53 PM	#6
cdowns Senior Member Join Date: Jan 2003 Location: daytonabeach Posts: 22,956	Re: Identifying a 4-Bolt Main Block 4bolts is muck ado about nothing mostly//2 bolts are fine up to 400 or so hp __________________ 71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY

10-03-2010, 05:42 PM	#7
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	Re: Identifying a 4-Bolt Main Block yep, sell the 4 bolts for top dollar, and buy the 2 bolt blocks for a fraction of the cost. If you wanna be a few steps ahead of the game, get a later 5.7 block with a one piece rear main seal and a roller cam.

10-04-2010, 12:00 AM	#9
po_bird Registered User Join Date: Oct 2005 Location: MUSKOGEE, OK Posts: 229	Re: Identifying a 4-Bolt Main Block Im with grx. The only thing you get from having a 4bolt is that you can say you have a 4bolt. __________________ 72 SIERRA LB 74 C10 SB 85 C10 SB 75 EL CAMINO SS



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.