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Appropriate engine?

VetteVirgin

Well-known member
Joined
May 20, 2009
Messages
52
Location
Las Vegas
Corvette
Ermine '61
Since purchasing my 61 I've been trying to determine exactly what type of engine is sitting under the hood and whether or not it is appropriate. Notice I did NOT say "correct". This is a driver and I'm more concerned with reliability and performance. That said, it wouldn't hurt if the components used actually had a bit of Corvette DNA also!
The previous owner told me the engine was a 350 that he thought came from a 80's Camaro. My own research has me leaning towards a very different possibility and has already eliminated the 80's Camaro.
What I have found is the following:
Block: 3970010 casting CE241361 stamping which makes it a 72 replacment casting from the Flint plant.
Heads: 3917291 "camel humps" F13 8 which makes them 68 heads. I know these were used on 68 275 and 325hp 327s. I am not sure about their use on 350s in 68.
Manifold: 3872783 cast iron/Holley carb intake for 66-68 327s.
Carb: Edelbrock 1406
I have not gone so far as dropping the oil pan to check the crank casting, which would definitively answer the dispacement issue.
So my current best guess based upon the accumulated evidence is that the original 283 was most likely replaced with a 68 327 which later required a block replacement in 72. Since 350 and 327 blocks are virtually identical with only the crank determining displacement, the previous owner assumed it was a 350.
I believe heads, intakes and blocks with these casting numbers were all used at one time or another on Corvette SBs in the 60's and 70's.
Does my conclusion seem likely? And more importantly, is this engine appropriate for a Corvette?
Thanks!

DT
 

Vettehead Mikey

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Aug 26, 2003
Messages
3,486
Location
Not that far from Ottawa
Corvette
1973 Coupe
Your engine could have come from just about any type car and could presently be built from just about any combination of internal components, GM or not. CE engine were frequently warranty replacement engines during the 5-50 warranty program years (long after your car was built) or were sold as over the counter replacement engines.

While you may have identified the block, head and intake casting numbers, the piston, crank, conrod and camshaft and remaining valve train components are unknown.

Is the engine 'appropriate'? If it makes the power you're looking for, I'd say yes.
 

BADBIRDCAGE

Well-known member
Joined
Jun 7, 2006
Messages
124
Location
Virginia Beach, Virginia
Corvette
1963 Polo Green Coupe
A 010 casting is a 4 bolt main large journal block. Many, many, many 010 blocks as 350's in passenger cars and trucks. Depending on stroke could be a large journal 302 but more likely a 350.

It is an appropriate block for a Corvette. As if that matters. Any small block is appropriate for a Corvette as long as it bolts in and works.

Rich:beer
 

VetteVirgin

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Joined
May 20, 2009
Messages
52
Location
Las Vegas
Corvette
Ermine '61
A 010 casting is a 4 bolt main large journal block. Many, many, many 010 blocks as 350's in passenger cars and trucks. Depending on stroke could be a large journal 302 but more likely a 350.

It is an appropriate block for a Corvette. As if that matters. Any small block is appropriate for a Corvette as long as it bolts in and works.

Rich:beer
Thanks! Actually the 010 casting could be 2 or 4 bolt. It was the most common 350 casting used.
The whole "appropriate" thing stems from a SCM article I read about a guy who bought a SWC that ended up having I believe a low HP truck engine in it. The SCM guy was all bent about that. Being new to Vettes I have no idea what "Vette think" is regarding engines except that you guys started the whole matching numbers craziness, so I assumed there would be definite opinions on what a Vette should and shouldn't have in the engine compartment.
These things are much simpler with the British roadsters I'm used to.
And I was wondering about the likelihood that it was a 327 instead of a 350. Same bore, just different stroke.
More importantly I'm trying to convince myself I don't need to spend 10K on a replacement engine. (ZZ4/LT1/CU code 283).
The engine runs fine, has good oil pressure, a lopey idle and adequate power. Perhaps its just the mystery that is eating at me.

DT
 

Tom Bryant

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7,395
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Edgerton, Ohio, United States
Corvette
1959 black 270hp (9/2/69) 1981 Beige L81(10/20/80)
327 large journal cranks are not very common. Most 327s were small journal like the 283 except for the last of them. 3917291 heads were used on 350s also in '67/'68 according to MorTec. Looks to me as if someone slipped a 350 in your car.

If you really want a CU code 283 in your car I have one I'd part with for a lot less than 10k less intake and carbs. Your car would need to be a late June or July '61 build date for it to match though.

Tom
 

VetteVirgin

Well-known member
Joined
May 20, 2009
Messages
52
Location
Las Vegas
Corvette
Ermine '61
OK, 350 it probably is then! The part that really didn't make sense to me for a 350 is the intake. It just didn't seem like something someone would keep on a 350, unless it is better than I think.
I have a Feb build car, but since you mention it, this is one of those things that I don't get about "correct" vette engines. Since 61 is the first year with ser. #'s stamped on the block, and since ANY engine I put in the car, whatever the date, will never be numbers matching, what difference does it make if there is a "correct" Dec/Jan CU/CT/CQ 283 in it or the exact same engine but with a slightly later (as in a few months) build date?
When I see people looking for exact build months for blocks for 61+ cars the first thing I think of is "restamp" and potential deception on resale.
I fully understand looking for the correct build date for pre-61 cars since without serial numbers, build date is all that matters, but if there is any difference in the value of a NOM 61 with a "correct" engine build date vs the same car with the same engine a month or two newer than the car build date, someone would have to explain why... very slowly...
I actually just turned down a "rebuilt" CU code with an April/May build date, no carbs and an incorrect intake for $3500. Too many other items ahead of replacing the engine at the moment such as the cooling system, Hot Rod Air, wrapping up the clutch, deciding if I'm masochistic enough to pull the instrument cluster to replace the tach, and replacing the front suspension bushings in the hopes of slightly reducing the steering slop, and I'm still flip-flopping between "period correct" and more modern reliability and efficiency. I'd probably just throw a modern throttle body or multipoint injection system on the existing engine if the fuel supply/return issue didn't seem like such a major pain.

DT
 

Vettehead Mikey

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Joined
Aug 26, 2003
Messages
3,486
Location
Not that far from Ottawa
Corvette
1973 Coupe
Sounds like you're stumbling on terminology.

'Numbers matching' always makes my skin crawl as it's been used to death and nebulous. Ask 10 people for a precise definition and you'll get 12 answers. I personally avoid use of the phrase for that reason.

'Correct' or 'restoration' engine usually mean an assembly of components that appears in ever detail to be typical of factory production for that particular car, but stops short of stating that it is the original.

Many people put extra value in having the 'original' engine in a car, which simply creates temptation by neer-do-wells to pass off 'restoration' engines as being 'original'.

You asked specifically about an engine that was cast/assembled a few months after the car was built- since this could not have possibly be the original engine it would carry less value (to some) than an other engine that was cast/assembled in the typical time frame of a few days up to a few months prior to car assembly date.

Hope this helps.
 

Tom Bryant

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Messages
7,395
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Edgerton, Ohio, United States
Corvette
1959 black 270hp (9/2/69) 1981 Beige L81(10/20/80)
Well said. The engine I have is an over the counter replacement with a F22CU stamping and no VIN. Since it has never been apart or decked, with a proper vin stamped from a car in the correct time period this engine would not be detectible from original. I removed it from a 1955 Corvette in 1975 and it was in there for several years before that. That takes it way back before anyone even thought about numbers matching or even cared.

I have been watching for a CU suffix block dated Sept or Oct '58 for my early '59 since I got it in 1969. I have all of the original components to my car except the block. I won't do a restamp and more than likely will never find a correct block. Some of this stuff is starting to resurface now that the boomers are retiring and liquidating cars and parts that they have been hording for decades. I may get lucky one of these days.

As for your intake, I'd guess that it was used more for hood clearance than anything else. My guess would be that the builder wanted to use the Holley but didn't want to pony up the big bucks for a 327/340 horse intake (which will clear the hood) or some other high rise which probably won't clear.

I would say as long as the 350 is performing well just drive it and enjoy. You can always keep an eye out and pick up original components to assemble a correct engine as you find them.

Tom
 

bwing

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Oct 28, 2005
Messages
517
Location
California
Corvette
03 Z06,66 coupe(sold),99 Porsche Carrera(sold)
To me, "numbers matching" equates to "did this stuff come on the car from the factory".
 

Vettehead Mikey

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Joined
Aug 26, 2003
Messages
3,486
Location
Not that far from Ottawa
Corvette
1973 Coupe
To me, "numbers matching" equates to "did this stuff come on the car from the factory".

OK, so that's one of the 12 different definitions I've heard. For bonus points, does this include components with no VIN identification?

If so, how do you know that it's the original piece or simply something found yesterday on eBay that used to be on a dump truck?

If not, that limits the components to the frame, engine block and transmission. What about all the other stuff? ;shrug
 
Joined
Jan 1, 2002
Messages
7,246
Location
Washington, Michigan
Corvette
'67 Marina Blue Convertible
You can be 99% sure that it's a 350 - the "CE" replacement engines were furnished as short-blocks, with all the external bolt-on items to be transferred from the failed engine. The only issue you'll have will be rigging a functional PCV system, as the 010 blocks don't have the rear crankcase vent hole that all '55-'67 blocks had. :thumb
 

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