Chevy Engine in my Jag.

framkiss

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Hello all,
Newbie on this site. I joined this forum because there is a lot of great info within the posts.
My name is Frank and I live in Florida. I will update my profile later tonight.
Anyway, I am trying to decode the engine I have in this car without (unless I have to) tearing the engine apart.
The engine codes I found are a little confusing as my search on the web only comes up with some info.
Engine Code: Left hand side Rear of engine is #3970010
Front of engine on the pad under the alternator: #16J11748. (partial VIN?)
Are there any other numbers I should be looking for to know for sure whether this engine is a 302/5?, 327 or a 350
I know I will have to drop the pan to verify whether it is a 2 bolt or a 4 bolt main
The engine runs great and has a 4 barrel 750 Holley Carb.
My plan is to convert this to EFI with a standalone unit from either Holley or FITECH but they would want to know the engine CC rating.
Any help with this will be greatly appreciated.
 

63Half-ton461

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Hi Frank from Florida, i'm 98% sure you've got a 350, if it was a 302 i think it would have DZ as part of that VIN, if it was a 327 it would be a very rare large journal crank unit that was made for one or two years around 68-69. 305 never used a 0010 block. The 0010 is a pretty common 4 inch bore block.
Pull a valve cover find and post what casting # the heads are, that will tell us .... a-lot !
 

63Half-ton461

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You have one of those jags with the turbo 400 trans ?
 

framkiss

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@ 63Half-ton461: Yes, I do, but since I am planning to convert to EFI, (once I figure out what engine I have), I will be swapping the turbo 400 for a 700R4.
I also found some other numbers stamped on the pad under the alternator.
The numbers are V0828CMJ. Using the web, I am not finding anything re: this number.
I will go back today and recheck the stamped numbers on the pad to see if I missed a digit or wrote one down incorrectly. Thank you all for the timely response.
 

63Half-ton461

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Cool! the 700 is a great hotrodder trany with its wide gear spread and overdrive, if im not mistaken the 700 and 400 are the same length and have the same spline count on the output shaft.

Definitely have a look under one of your valve covers for the casting # so we can figure out what heads you've got ...
 

framkiss

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As stated in my previous post the stamped ID on the plate under the alternator is V0828CMJ and the numbers at the rear of the engine block is 3970010.
Doing some research I found this from "Nasty Z28" The CMJ means the following:
CMJ1974
350​
t4OO police -4full size
CMJ1980
305​
automatic trans.H--full size/Camaro
So is the engine a 305 or a 350?
I will be pulling the valve covers in a couple of days and will post the numbers I find there.
 

63Half-ton461

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The 3970010 is a 4 inch bore block, it was never used in 305 production, so when 3970010 is combined with CMJ that points toward the 1974 350.
Yup cylinder head casting # can further confirm production time frame and engine application
 

framkiss

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I pulled the valve cover today and the head casting is #333882.
I heard that these heads are prone to cracking. I am not looking for high performance. This is just a cruiser.
If this is the case, what is the best replacement heads I can use?
 

63Half-ton461

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333882.....74-80...350/400......76cc chambers

Mortec lists this head as being in production for 6 years but i think it was much longer when you include crate motor (Goodwrench) production.
I've never heard of 882's being prone to cracking but its possible they thinned out the casting in later years of production and that occurs occasionally.
It sounds like you may have a older motor so you've probably got the older heavier heads.

All that being said, 882's have more of a reputation for being a low compression smog head with a fairly inefficient combustion chamber. Carbureted 350's with 882 heads get horrendous fuel economy with the best i've ever personally got being 13mph from my Blazer and maybe 14-15 from my Pontiac lemans (That's from a canadian gallon)
Much more efficient heads were put on motors in the early 90's, Gm's TBI motors, some were swirl port heads. all the chambers were smaller 64cc with improved spark plug location, unfortunately they are thin wall castings so you have to look for good uncracked un-abused sets and then not abuse them yourself,
I ran a TBI swirl port carbureted 350 with the 193 castings in my Malibu Skier and i used to cruze at 4800 rpm and 50 mph with no issues.
So yeah if your thinking fuel injection you might want to consider a head swap as part of that plan as well, TBI or Vortec heads, the Vortec being more highly touted.
 

63Half-ton461

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I have the older version of that Pro-flo system but for big block, the one your looking at is the 4th design and in my opinion is one of the best out there, your buying into some 20 years of development and that system was darn good to start with, my controller is pretty basic compared to what your getting. Once you learn to navigate the menu its pretty straightforward. What i like about Edelbrock is they still support my older system and sell parts and upgrades for it. The institutions are pretty good too from fuel tank to engine and what everything does. The first time you drive it to after having run a carb, its pretty rock solid.
 
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