I am looking for second opinions on what the engine is from in my 67 vert. No original drivetrain components were left in it when I bought it a couple years ago.:( (It had seen its share of Hot Rodding!) Anyway, half the decode sites say it is a 283 and the other half say it is a 327. It revs like a 283 but has more torque and HP than you would expect from a 283.
I originally thought it was a 283 out of an Impala or other full size Chevy but now I am second guessing myself

Here are the numbers.

Block casting 3789817
Head castings 3814482

Both block and heads (and just about everthing else for that matter) have June 62 casting dates.

Engine pad stamp is T0625C.


This looks to be a complete engine that was swapped, most likely after the original was blown apart, (Starter, distributor, water pump, intake are all May or June 62). another thing that is confusing me is the research I have done says the heads are 75 cc. But from the way the engine runs and sounds it has to have around a 10 to 1 CR +/-. This makes me think someone might have put domed pistons in it, but then if they were going to do that, why didn't they use a better breathing set of heads.

Hopefully someone can tell me what I have now. I still plan on putting a 383 in it eventually, but since the mystery engine in it now runs so well I have put the 383 on the back burner until I fix/restore other areas that need more immediate attention. (plus building a new house).

Thanks for your time and help.

Victor

67 vert
W 2LG 3L 4P

P.S. Would a June 26, 62 build date be for a 62 of 63 model year car.

Block casting 3789817 is a 62-63 327 block

Head castings 3814482 were used on 327's also

Looks like you got a 283 built 0625 or June 25th

Chevy Small Block Engine Suffix Codes [C-CZZ]
Code Year CID HP BB LA ppl
C 1958 283 185 2 m/t, 3 spd
C 1960 283 170 2 m/t
C 1957 265 - m/t, 3 spd



Casting
3789817 1958-68 283 2

Yeah, we are clearing this right up for ya.

I have the following...

Block casting no. 1962-67 3789817 327 210 275 2 car, truck
Head casting no. 1962-67 3814482 283,327 1.72 1.5001

I'm betting your stamp is actually TO62SC, which gives this:

1962 SC 327 Powerglide - 250 4 Vette

If original 283 engine with its own parts, the harmonic balancer will be thin, ie, 1/2 inch wide for 283/265, 3/4 inch wide for 327/307.

Thanks for the replies. I guess you can see why this has confused me.

Eric, the pad stamp is definately T0625C (although it would have been nice to have an old vette motor).

Everette, The balancer looks to be original and it is 1/2" thick so I guess it is or was a 283.

I haven't taken it to the track yet which I would like to do, just for a baseline time, but I have enough experience with motors to say this thing is pushing between 275 to 300 HP which is another thing that baffles me. Its got a performer 2101 intake manifold, a 795 cfm quadrajet (I have the original intake manifold and 2 bbl carb for it though) and full length headers. As I mentioned before, the CR has to be around 10 to 1 +/- and the engine spins and pulls like crazy on the upper RPM. This makes me think someone had to have replaced the stock cam and pistons, since I am showing the head casting as a 75cc head. I guess I need to pull the heads to see what's going on with the pistons and verify the bore size. Is there a way to identify what kind of cam is in the engine without pulling it (casting or part number location)?

Any way thanks for all the help.


Victor

67 vert
w 2LG 3L 4P

Well - to add to your confusion...
Maybe an "Old-s-Cool" mechanic got ahold of your engine... ;)

I built several motors back-in-the-day for my, and friends, vehicles that used the later 3.875" '283' blocks bored out and fitted them with 3.25" 327 'small journal' cranks.These cranks are a 'drop-in' on these blocks.
These would give me up to @ 316 C.I. engine that would rev. much like the smaller bore 283 and had very good torque numbers, much better than could be achieved normally than by just boring and building a 3.0" cranked unit.
With a good set of heads, cam, intake, Holley, headers and tuning, HP numbers in the 400(+) range were not hard to get.
These smaller displacement engines have excellent street power curves and performed well with the then available smaller runner aftermarket intakes that are much like the 2101 unit you have.
Throttle response on a properly set-up engine was very impressive :thumbsup:
It was also common for me to use the smaller stock 283 type dampers as they 'were there', worked just fine on these small quick reving engines and fit with all the original pulleys ect... Part number was #3861970 (had to go look it up in a build sheet...).
You can 'CC' a cylinder if you really want to determine the exact displacement.
The heads have @75cc chambers and they would help lower the compression ratio, if they assembled the unit with flat tops, to where you probably wouldn't have detonation issues like you would if they used a smaller 62~65cc performance head.
These smaller valve heads will help your torque numbers and throttle response in the lower rpm ranges and won't really hurt the HP until you get above the 6500rpm range on these small inch motors. A small trick to improve flow with the smaller lift cams common at the time, other than just some minor porting, was to fit them with 1.6" BB rockers to improve flow on the upper end. This and a some good springs could easily get these motors to the 7500(+) rpm range with good HP numbers.
A good set of small tube headers really helped also.


I gotta go take a nap now...
John

ps: hmmmm - I was just thinkin' - I have a 307 block, a med. journal 3.25" crank and a set of 267 heads in the shop... maybe I should see what happens if I throw that mess together :D

Victor, put a vacuum gauge onto the intake and tell us how much vacuum is being created. This will tell some about the cam profile.

I agree with John, I've got a mint '81 350-4-bolt block, 327 forged crank, 300 hp cam, but no heads yet. If I get a set of 482 heads, it'll scream..........

Everett,

I am planning on putting the Vacuum gauge on the manifold to see what it is pulling and I will start a new thread over in Engines with the results.

But I was wondering, the engine still has the road draft tube and it isn't plugged up. Will this affect the vacuum reading?

Thanks again for all of the help guys!:beers:


Victor

67 vert
W 2LG 3L 4P

Everett,

But I was wondering, the engine still has the road draft tube and it isn't plugged up. Will this affect the vacuum reading?

Thanks again for all of the help guys!:beers:


No.

Okay,

I ran the compression and vacuum tests awhile back, then misplaced the paper I wrote them down on. Here are the numbers:

Vacuum 12" Hg at idle.

Compression numbers (Static):

#1 165
#3 160
#5 165
#7 170
#2 165
#4 165
#6 165
#8 170

I also found out I misread my own writing of the cylinder heads, the correct casting number is 3814480 not 3814482 as I originally posted, the difference as far as I can tell is that the listed size of the chamber are 70cc instead of 75, which explains the compression thing, at least a little bit.

I also found the distributor # which is 1112057, and the vacuum cannister has the numbers 436 20 on the top of the bracket. I assumed it was the original distributor to the engine , but I guess it is a 72 distributor, not a 62. The motor has to be a 62 date as from my info and the info I have gooten here since the casting was not made in 72. The reference I have on the distributor # says it is for a 71-72 Fullsize, Camaro, Chevelle and Mote Carlo with a 402 ci.

If this is correct, why would someone put a big block distributor on a 283 (or possibly a stroked and bored 283), and could this be the cause of the excessive vertical freeplay of the distrubutor (a little over 1/8")? How would this vacuum cannister be influencing the advance?

Thanks again for the help.

Victor

67 vert
W 2LG 3L 4P