engine id help - The 1947 - Present Chevrolet & GMC Truck Message Board Network

kljfamily · 10-25-2020, 01:49 PM

1968 engine chevy

Hello,

I searched the net and did my research before posting this fyi.

I think I have found out the info I need bug want to bounce it off this forum.

What I have is an engine I got on trade.(zero history)

the code on the rear of the engine is GM 3914678 there is also a 19 stamped before the gm part at a 90 degree angle.

to the right is what I believe is the date code g28 which I believe is ajuly 2 1968

So looking it up it comes up as a possible camero engine from 1968 but that same casting number was used in the 302 327 and 350 of that year.

There would normally be additional codes on the front plate but looks like it was possibly decked as its a clean plate. I can just barely made out a c and maybe an 8.

on the back of the motor there are some more numbers h33 on one side and 371 above a 386 and 636 above 678.

the crank is in it and that is stamped 3932442 which should be a 350 crank so I am thinking that is what i have.

anyways I want to sell the block but want to make sure I am being honest in the add. I am working on a 65 c10 but want to keep it original to the i6.

Hopefully this block is worth some $ to help with the purchase of the motor.

The block has crank/cam but no cylinders.

thanks

Kris

**cwcarpenter98** · 10-25-2020, 02:11 PM

I would measure the diameter of the bore if there's no heads on the engine. That will make it easier to narrow down on the size since the casting number is the same

kljfamily · 10-25-2020, 02:15 PM

with the digital calipers the bore measures 4.02

but I believe the 327 and the 350 had the same bore with different stroked. the 327 had a 3.25 stroke and the 350 3.48

so I know the crank in there has a 3.48 but could a 350 crank be used in a 327?

SkinnyG · 10-25-2020, 03:49 PM

If they share the same main journal diameters, yes. That block is for a 302, 327, and a 350 - they all use 4" bore - the difference is the crankshaft.

**cwcarpenter98** · 10-25-2020, 03:52 PM

Whoops, that shows my inexperience with engines. Always learning though

kljfamily · 10-25-2020, 04:34 PM

Quote:

Originally Posted by SkinnyG

If they share the same main journal diameters, yes. That block is for a 302, 327, and a 350 - they all use 4" bore - the difference is the crankshaft.

so similar to the inline 6 230 verse 250 same block but different stroke. I get it. thanks

**Captainfab** · 10-25-2020, 09:25 PM

The suffix code stamped on the pad just forward of where the passenger side head would be will tell you exactly what it is and what it came out of.

10-25-2020, 01:49 PM	#1
kljfamily Registered User Join Date: Sep 2014 Location: Albuquerque NM Posts: 98	engine id help 1968 engine chevy Hello, I searched the net and did my research before posting this fyi. I think I have found out the info I need bug want to bounce it off this forum. What I have is an engine I got on trade.(zero history) the code on the rear of the engine is GM 3914678 there is also a 19 stamped before the gm part at a 90 degree angle. to the right is what I believe is the date code g28 which I believe is ajuly 2 1968 So looking it up it comes up as a possible camero engine from 1968 but that same casting number was used in the 302 327 and 350 of that year. There would normally be additional codes on the front plate but looks like it was possibly decked as its a clean plate. I can just barely made out a c and maybe an 8. on the back of the motor there are some more numbers h33 on one side and 371 above a 386 and 636 above 678. the crank is in it and that is stamped 3932442 which should be a 350 crank so I am thinking that is what i have. anyways I want to sell the block but want to make sure I am being honest in the add. I am working on a 65 c10 but want to keep it original to the i6. Hopefully this block is worth some $ to help with the purchase of the motor. The block has crank/cam but no cylinders. thanks Kris

10-25-2020, 02:11 PM	#2
cwcarpenter98 Senior Member Join Date: Jan 2018 Location: Hickory Flat, GA Posts: 4,491	Re: engine id help I would measure the diameter of the bore if there's no heads on the engine. That will make it easier to narrow down on the size since the casting number is the same __________________ Christian Carpenter 1963 C10 - Frankentruck 283, Muncie 3 speed with overdrive Overdrive wiring here 1963-ish truck bed trailer - Half-Wit 1981 C10 - Penny 305, th350 --> Soon to be 350, Saginaw 4 speed 1995 Dodge Dakota Sport "I'll put it simple: if you're going hard enough left, you'll find yourself turning right." - Doc Hudson

10-25-2020, 02:15 PM	#3
kljfamily Registered User Join Date: Sep 2014 Location: Albuquerque NM Posts: 98	Re: engine id help with the digital calipers the bore measures 4.02 but I believe the 327 and the 350 had the same bore with different stroked. the 327 had a 3.25 stroke and the 350 3.48 so I know the crank in there has a 3.48 but could a 350 crank be used in a 327?

10-25-2020, 03:49 PM	#4
SkinnyG Registered User Join Date: Feb 2012 Location: Beautiful BC, Canada, eh?! Posts: 2,267	Re: engine id help If they share the same main journal diameters, yes. That block is for a 302, 327, and a 350 - they all use 4" bore - the difference is the crankshaft. __________________ 1961 Apache: "Grabber Orange" Shortboxed, pancake, step-notch, air-ride, turbo, LS 1977 Silverado: Shortboxed & dropped, potato-potato V8 Pontiac Firefly (Chevy Sprint): The ultimate engine swap: 5.7L in a 1.0L bag Lotus Super 7 Replica: Scratch-built street-legal rollerskate

10-25-2020, 03:52 PM	#5
cwcarpenter98 Senior Member Join Date: Jan 2018 Location: Hickory Flat, GA Posts: 4,491	Re: engine id help Whoops, that shows my inexperience with engines. Always learning though __________________ Christian Carpenter 1963 C10 - Frankentruck 283, Muncie 3 speed with overdrive Overdrive wiring here 1963-ish truck bed trailer - Half-Wit 1981 C10 - Penny 305, th350 --> Soon to be 350, Saginaw 4 speed 1995 Dodge Dakota Sport "I'll put it simple: if you're going hard enough left, you'll find yourself turning right." - Doc Hudson

10-25-2020, 09:25 PM	#7
Captainfab 60-66 Nut Join Date: Mar 2007 Location: Coeur d'Alene, Idaho Posts: 23,252	Re: engine id help The suffix code stamped on the pad just forward of where the passenger side head would be will tell you exactly what it is and what it came out of. __________________ Power Steering Box Adapter Plates For Sale HERE Power Brake Booster Adapter Brackets For Sale '63-'66 HERE and '67-'72 HERE and '60-'62 HERE and "60-'62 with clutch HERE Rear Disc Brake Brackets For Sale. Impala SS calipers HERE Camaro Calipers HERE D52 Calipers HERE 6 Lug HERE Hydroboost Mounting Plates HERE



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