Were there any 4 bolt mains other than 350s? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Longhorn 70 · 10-31-2013, 02:33 PM

Just curious. Were small block Chevys ever released from the factory in our trucks, in any displacement other than 350 C.I.D.?

**kwmech** · 10-31-2013, 02:40 PM

There was a 4 bolt main 400 cubic inch and I think the 302 in 68 was a 4 bolt

**truckdude239** · 10-31-2013, 03:19 PM

there was a 4 bolt 327 but it was used in the old massey ferguson tractors

*Fitz* · 10-31-2013, 04:09 PM

Quote:

Originally Posted by Longhorn 70

Just curious. Were small block Chevys ever released from the factory in our trucks, in any displacement other than 350 C.I.D.?

General Engine Block Specifications. 6 different bore size blocks have been produced, the small block engine can be classified into 3 bore sizes and 3 main bearing sizes. 283 blocks (3.875" bore, 2.3" main),
302/327/350 blocks (4" bore, 2.3" or 2.45" mains),
and 400 blocks (4.126", 2.65" mains).
In 1968 the main bearing saddles were increased in size from 2.3" to 2.45".

CID Year Bore Main Cap
262 1975 3.671 2 bolt ONLY
267 1979 - 81 3.500 2 bolt ONLY
305 1976 - 96 3.736 2 bolt ONLY
307 1968 - 73 3.875 2 bolt ONLY
327 1968-69 4.001 (2.3" main) 2 bolt
350 1968-88 4.001 (2.3" main) 2 bolt
265 1994 4.001 (2.45" main) 2 bolt
302 1968-69 4.001 (2.45" main) 4 bolt
350 1968-96 4.001 (2.45" main) 4 bolt
400 1970-72 4.126 (2.65" main) 4 bolt
400 1973-80 4.126 (2.65" main) 2 bolt

Notes: 2 bolt ONLY means just that,. otherwise 2 or 4 bolt can mean either design... interpret that to mean that there "Could" be a 4 bolt 327 built in 68-69 for the Camaro as was the 302 from those same years which went into the Z28. There are no records from the GM Historical center showing what went into the C-10's other than the 2 bolt 327's and the 4 bolt 400's but those records might be incomplete or inaccurate.

Longhorn 70 · 10-31-2013, 05:13 PM

Great Info! Thank you. I'd only wonderded as I bought a "350" used.

I didn't know if they did 307's in 4 bolt.

I pulled the pan on this one to look at the bearings change the oil pump coupler, secure the pick up and seal some leaks. I do know it's 4 bolt but didn't measure the bore or stroke.

Thank you again.

wreckedchevy · 10-31-2013, 05:17 PM

Quote:

Originally Posted by truckdude239

there was a 4 bolt 327 but it was used in the old massey ferguson tractors

that's what's in our really old combine would be a fun one to build the hell out of.

**special-K** · 11-01-2013, 09:20 AM

There are definitely 4-bolt 327s. The '68 truck engine I have is an 010 casting,which is a 4-bolt large journal. IIRC,it's the same block as the '68 Camaro SS350 as well as the Z/28 302. High nickle and steel crank,too!

Eddie H. · 11-01-2013, 09:28 AM

Quote:

Originally Posted by wreckedchevy

that's what's in our really old combine would be a fun one to build the hell out of.

If I remember correctly, some of the old combines used a turbocharged 327.
I don't know what kind of internals it had, but I would bet that it had forged pistons and crankshaft.

mmiddle · 11-01-2013, 10:36 AM

The 67-68 MO302's were 2 bolt Z/28 only. The 69 DZ302 is 4 bolt large journal Z/28 only. Some 327's were 4 bolt, but late 67-68 large journal. Some 70-72 400's are 4 bolt. Then 350's could be either depending the application.

To be honest GM did alot a weird things back in the late 60 early 70's. The strikes in 68,69,70 brought about a lot of parts swapping. For one, Tonawanda engine plant was a big block plant, yet in 69-70 they built some small blocks.

*Fitz* · 11-01-2013, 12:35 PM

Quote:

Originally Posted by special-K

There are definitely 4-bolt 327s. The '68 truck engine I have is an 010 casting,which is a 4-bolt large journal. IIRC,it's the same block as the '68 Camaro SS350 as well as the Z/28 302. High nickle and steel crank,too!

That is a VERY nice motor.

10-31-2013, 02:33 PM	#1
Longhorn 70 Registered User Join Date: Dec 2012 Location: Chandler AZ Posts: 1,149	Were there any 4 bolt mains other than 350s? Just curious. Were small block Chevys ever released from the factory in our trucks, in any displacement other than 350 C.I.D.? __________________ 1970 Longhorn, Front Disc, 350/4 bolt, 882 heads, HEI, Edelbrock, 700R4, HO-52/4.11. 1996 Corvette, Collector Roadster, LT4, 396, 450RWHP, 6sp, 4.11/Dana44/posi 5 point roll bar And let us not grow weary of doing good, for in due season we will reap, if we do not give up. Gal 6:9

10-31-2013, 02:40 PM	#2
kwmech Senior Member Join Date: Mar 2003 Location: Colfax-California Posts: 8,482	Re: Were there any 4 bolt mains other than 350s? There was a 4 bolt main 400 cubic inch and I think the 302 in 68 was a 4 bolt

10-31-2013, 03:19 PM	#3
truckdude239 Senior Member Join Date: Sep 2005 Location: Lewisville, Nc Posts: 10,230	Re: Were there any 4 bolt mains other than 350s? there was a 4 bolt 327 but it was used in the old massey ferguson tractors __________________ David fuller Ase Certified Mechanic Click here to help support our board!! 1971 Chevy c-10 under going a 4.8l LSx swap Build Thread http://67-72chevytrucks.com/vboard/s...d.php?t=421305 2007 Honda Accord my daily 145kmiles 2002 Honda Accord 4 door With 330k(sisters car) 2005 toyota Avalon 228k( brothers car) 2002 Sububran 5.3 245k 2000 Tahoe 5.3l 378 General manager for Marco's Carwash & lube

10-31-2013, 05:13 PM	#5
Longhorn 70 Registered User Join Date: Dec 2012 Location: Chandler AZ Posts: 1,149	Re: Were there any 4 bolt mains other than 350s? Great Info! Thank you. I'd only wonderded as I bought a "350" used. I didn't know if they did 307's in 4 bolt. I pulled the pan on this one to look at the bearings change the oil pump coupler, secure the pick up and seal some leaks. I do know it's 4 bolt but didn't measure the bore or stroke. Thank you again. __________________ 1970 Longhorn, Front Disc, 350/4 bolt, 882 heads, HEI, Edelbrock, 700R4, HO-52/4.11. 1996 Corvette, Collector Roadster, LT4, 396, 450RWHP, 6sp, 4.11/Dana44/posi 5 point roll bar And let us not grow weary of doing good, for in due season we will reap, if we do not give up. Gal 6:9

11-01-2013, 09:20 AM	#7
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,862	Re: Were there any 4 bolt mains other than 350s? There are definitely 4-bolt 327s. The '68 truck engine I have is an 010 casting,which is a 4-bolt large journal. IIRC,it's the same block as the '68 Camaro SS350 as well as the Z/28 302. High nickle and steel crank,too! __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

11-01-2013, 10:36 AM	#9
mmiddle Registered User Join Date: Jul 2013 Location: Forestburg, Texas Posts: 659	Re: Were there any 4 bolt mains other than 350s? The 67-68 MO302's were 2 bolt Z/28 only. The 69 DZ302 is 4 bolt large journal Z/28 only. Some 327's were 4 bolt, but late 67-68 large journal. Some 70-72 400's are 4 bolt. Then 350's could be either depending the application. To be honest GM did alot a weird things back in the late 60 early 70's. The strikes in 68,69,70 brought about a lot of parts swapping. For one, Tonawanda engine plant was a big block plant, yet in 69-70 they built some small blocks. __________________ Mark Jesus is the Way! 2003 2500HD CCLB Duramax/Ali (Clifford) 2014 2SS/RS black on black Camaro (Betty) 2006 Pontiac SOLSTICE silver/black (Lula-Bell) 1970 C/10 Short Wide (Peggy) 1964 C/10 Short Step (Hambone) RIP Jimmy Hamilton Thank you for the trucks



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