Chevy Small Block Parts... 67-68 change? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

toms68cst · 06-04-2002, 12:08 AM

Why is it when you see Chevy small block parts (Like rebuild kits) advertised on ebay or somewhere else do all the years range ..... - 67 and 68 - .......? It always seems like there is always a break between 67 and 68. Were there any major changes were made to the small block between 67-68?

I'm thinking of the 327/350 which of course was available through those years. There always seems to be a break at the 67-68 years.

The only thing that comes to my mind is the introduction of smog controls in 68. If thats the case how would other engine parts change?

Pont · 06-04-2002, 12:25 AM

Older 327's were small journal and newer were large journal. The 350 (rarely available from 67) would be the same as large journal.
If my memory serves me correctly. It's been more than 10 years since I've played with old small blocks.

**68SWB4x4** · 06-04-2002, 12:27 AM

yes in 1968 the 327 went to large journal

mikep · 06-04-2002, 12:40 AM

Big changes in 68 and 69.

Rod and main journals were increased in size in 68 .

The 327 held on through 1968 but was eliminated in the 1969 model year in favor of the 350 which made its appearance in 1968 with its 3.48 stroke.

The 4 bolt main was introduced in the small block lineup in the 350 and 302 in 1968.

The 283 picked up the 327 crankshaft and became the 307 and what formerly was the hot ticket for boosting up a 283 became the newest dog motor in the lineup.

Breathers and oil filler were moved to the valve covers from the intake manifold for a PCV system instead of the road draft system used previously.

The long water pump system began to take over in late 68 which allowed for more accesory mounting in conjunction with the new bolt hole heads and allowed for easier interchangeability between small block and big block accesories and mounts.

toms68cst · 06-04-2002, 08:27 AM

Thanks for all the good info folks. I've always wondered about that.

*Fast68Chevy* · 06-04-2002, 11:27 AM

mike, you are oen year off, 69 was first year for 4 bolt and for the long water pumps, sorry

tom hand · 06-04-2002, 12:58 PM

Mike you are right on the 4 Bolt main, first year was 68 on 350's and 302's

http://www.nastyz28.com/sbchevy/sblock.html

mikep · 06-04-2002, 07:22 PM

Yes it was early 68 that the 4 bolt mains were introduced both in 350 and 302 and the long water pump was introduced in 1968 as in the year 1968 not the model year 1968.

Blazer1970 · 06-04-2002, 07:29 PM

Anyone reading this note that trucks did not go to the long water pump until the '73 model year. The larger bearings are the reason for the difference in rebuild kits.

mikep · 06-04-2002, 07:47 PM

Of course trucks were 73 on the water pump setup. Passenger car engines started earlier.

breeh · 06-04-2002, 09:10 PM

Just as a "fun fact", the 350 was introduced in 1967 as a Camaro only option.

06-04-2002, 12:08 AM	#1
toms68cst Registered User Join Date: Jun 2000 Location: Bismarck, ND Posts: 4,297	Chevy Small Block Parts... 67-68 change? Why is it when you see Chevy small block parts (Like rebuild kits) advertised on ebay or somewhere else do all the years range ..... - 67 and 68 - .......? It always seems like there is always a break between 67 and 68. Were there any major changes were made to the small block between 67-68? I'm thinking of the 327/350 which of course was available through those years. There always seems to be a break at the 67-68 years. The only thing that comes to my mind is the introduction of smog controls in 68. If thats the case how would other engine parts change? __________________ Unrestored 68 C-10 CST. Original 327. 4-Speed CH465. 50k or so miles. TREASURER, Drum Brake Club.

06-04-2002, 12:25 AM	#2
Pont I need another Barley Pop Join Date: Feb 2001 Location: Grants Pass, OR Posts: 1,629	Older 327's were small journal and newer were large journal. The 350 (rarely available from 67) would be the same as large journal. If my memory serves me correctly. It's been more than 10 years since I've played with old small blocks. __________________ 67 Short Fleet 4x4 04 Honda CRF450R 89 Toyota 4-Runner 34 Ford 2 door sedan - Long term project ---------------------------------------------- There is a very fine line between "hobby" and "mental illness"

06-04-2002, 12:27 AM	#3
68SWB4x4 Strongman Garage Join Date: Apr 2000 Location: Salinas, CA Posts: 10,241	yes in 1968 the 327 went to large journal __________________ Kalle 68 GMC Suburban 1500 4x4 SOLD 69 Pontiac Lemans 99 Silverado 4.8 5 speed ECSB [ Facebook Instagram Subscribe on YOUTUBE

06-04-2002, 12:40 AM	#4
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	Big changes in 68 and 69. Rod and main journals were increased in size in 68 . The 327 held on through 1968 but was eliminated in the 1969 model year in favor of the 350 which made its appearance in 1968 with its 3.48 stroke. The 4 bolt main was introduced in the small block lineup in the 350 and 302 in 1968. The 283 picked up the 327 crankshaft and became the 307 and what formerly was the hot ticket for boosting up a 283 became the newest dog motor in the lineup. Breathers and oil filler were moved to the valve covers from the intake manifold for a PCV system instead of the road draft system used previously. The long water pump system began to take over in late 68 which allowed for more accesory mounting in conjunction with the new bolt hole heads and allowed for easier interchangeability between small block and big block accesories and mounts. __________________ No truck :-( Last edited by mikep; 06-04-2002 at 12:42 AM.

06-04-2002, 08:27 AM	#5
toms68cst Registered User Join Date: Jun 2000 Location: Bismarck, ND Posts: 4,297	Thanks for all the good info folks. I've always wondered about that. __________________ Unrestored 68 C-10 CST. Original 327. 4-Speed CH465. 50k or so miles. TREASURER, Drum Brake Club.

06-04-2002, 11:27 AM	#6
Fast68Chevy Account Suspended Join Date: May 2000 Location: IL Posts: 0	mike, you are oen year off, 69 was first year for 4 bolt and for the long water pumps, sorry

06-04-2002, 12:58 PM	#7
tom hand CCRider Join Date: Feb 2000 Location: Olive Branch,MS,USA Posts: 2,232	Mike you are right on the 4 Bolt main, first year was 68 on 350's and 302's http://www.nastyz28.com/sbchevy/sblock.html __________________ 72 GMC Sierra SWB almost finished---- 84 Softail Olive Branch MS

06-04-2002, 07:22 PM	#8
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	Yes it was early 68 that the 4 bolt mains were introduced both in 350 and 302 and the long water pump was introduced in 1968 as in the year 1968 not the model year 1968. __________________ No truck :-(

06-04-2002, 07:29 PM	#9
Blazer1970 Registered User Join Date: Dec 1999 Location: Old Mission, MI, USA Posts: 2,507	Anyone reading this note that trucks did not go to the long water pump until the '73 model year. The larger bearings are the reason for the difference in rebuild kits. __________________ Tim

06-04-2002, 07:47 PM	#10
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	Of course trucks were 73 on the water pump setup. Passenger car engines started earlier. __________________ No truck :-(

06-04-2002, 09:10 PM	#11
breeh Recovering 67-72 Addict Join Date: Oct 2000 Location: North Bend, WA Posts: 1,788	Just as a "fun fact", the 350 was introduced in 1967 as a Camaro only option. __________________ 68 Short Fleet 4x4; 427; BTO Level 3 700R4; NP205; Dana 60 front and rear; 4" lift with 35's; Disc brakes; AGR variable ratio steering; factory bucket seats; factory tach and tilt. "Friends call me cruzer cuz I like fast cars and fast women"



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