327 or 350
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,912
Likes: 12
From: Schaumburg (Chicago) Illinois
327 or 350
I have a 68 vert. Don't believe it is the original engine. I want to buy complete exhaust system.
Simple questions that I need answers for:
How do I tell if it is a 327 or a 350?
How do I tell if it is a Vette engine?
How do I tell what HP it is?
As far as the exhaust goes, does it matter if it is a 327 or a 350?
Thanks!!
Simple questions that I need answers for:
How do I tell if it is a 327 or a 350?
How do I tell if it is a Vette engine?
How do I tell what HP it is?
As far as the exhaust goes, does it matter if it is a 327 or a 350?
Thanks!!
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
On the block, at the right front there is a pad with some numbers. Get those numbers and there are lots of books that will tell you everything you're looking for. As far as the exhaust- no difference.
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,482
From: Southbound
Cruise-In II Veteran
Block casting number on the web near the bellhousing. 327s are 3914678; 350s are 3932386 or 3970010. Jot down what you find and post it here.
Engine ID stamp on the block pad at the front of the right head.
No, but it wouldn't hurt to now exactly what you have.
...How do I tell if it is a Vette engine?...How do I tell what HP it is?...
...As far as the exhaust goes, does it matter if it is a 327 or a 350?...
Le Mans Master
Joined: Jun 2003
Posts: 5,135
Likes: 71
From: Umeå Sweden
look at the back of the block there you have some numbers also:
also you have some numbers on the heads if you remove the covers:
tell us what you got
also you have some numbers on the heads if you remove the covers:
tell us what you got
Last edited by stingraymaniac; May 4, 2007 at 04:42 PM.
Melting Slicks
Joined: Sep 2006
Posts: 3,382
Likes: 2,605
From: Burning Jet-A
I would say that it could be one of the three below. The casting date of the block will narrow it down from the 1970 to the 1979, What these are are truck motors, so you may have a 3970020 casting. A 4 bolt I think. The key is that any small block once NOM can be built to be awesome. They are truly great platforms and what it was born in is of no consequence. Its possible that many years ago someone bought a rebuilt 350 from a big parts house built to some spec and put it in the car. What heads do you have?
TBC 1970 350 convfwd cabs, a/t 255HP 4bbl C-10 to 3500
TBC 1970 350 m/t, 3 spd 255HP 4 bbl K-10 & 20
TBC 1979 350 conv. cab, m/t,fed L LS9 165HP 4bbl C-10 to 2500
TBC 1970 350 convfwd cabs, a/t 255HP 4bbl C-10 to 3500
TBC 1970 350 m/t, 3 spd 255HP 4 bbl K-10 & 20
TBC 1979 350 conv. cab, m/t,fed L LS9 165HP 4bbl C-10 to 2500
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Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,912
Likes: 12
From: Schaumburg (Chicago) Illinois
I appreciate your help.
So does this mean these are good breathing heads or not?
Block casting number appears to have been ground off. I can see the heavy grind marks. but the first digit, a "3" is still mostly there. The rest is gone. next to that is "6GM"
Then there are 3 other markings:
A bunch of dots in a circular pattern with a tear drop shape in the middle. One of the dots has another dot above it. The tear drop points just after the 5th dot clockwise. The 5th dot defined as the 5th dot after the double dot. In otherwords not including the double dot. Or in otherwords like a clock you don't count the 12 you start with 1.
I hope that isn't more confusing!
Then there is 3 letters, "T, D, N", in a radius around another teardrop. The teardrop points to the side just counterclockwise of the "T". In otherwise going counterclockwise, just to the left of the "T"
There are what look like screws, but they are cast in. So in order:
screw, 3, screw, H10, screw.
So does this mean these are good breathing heads or not?
Block casting number appears to have been ground off. I can see the heavy grind marks. but the first digit, a "3" is still mostly there. The rest is gone. next to that is "6GM"
Then there are 3 other markings:
A bunch of dots in a circular pattern with a tear drop shape in the middle. One of the dots has another dot above it. The tear drop points just after the 5th dot clockwise. The 5th dot defined as the 5th dot after the double dot. In otherwords not including the double dot. Or in otherwords like a clock you don't count the 12 you start with 1.
I hope that isn't more confusing!
Then there is 3 letters, "T, D, N", in a radius around another teardrop. The teardrop points to the side just counterclockwise of the "T". In otherwise going counterclockwise, just to the left of the "T"
There are what look like screws, but they are cast in. So in order:
screw, 3, screw, H10, screw.
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,912
Likes: 12
From: Schaumburg (Chicago) Illinois
Ok, I see. My Corvette black book does show these heads for 71 and 72.
That also seems to mean it is a 350 engine. please confirm.
And I show the H200 on my heads, does this mean horsepower? Because the black book for 72 shows that head for both 200 and 255 horsepower.
That also seems to mean it is a 350 engine. please confirm.
And I show the H200 on my heads, does this mean horsepower? Because the black book for 72 shows that head for both 200 and 255 horsepower.
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,912
Likes: 12
From: Schaumburg (Chicago) Illinois
more info
Closer review of the block number shows that the last third of the last digit is still there. It is either a 3,8, 0 or a 9. So block is one of these:
3914678 327ci 1968
3932388 350ci 1969
3956618 350ci 1969
3970010 - very, very common 69-80
376450 350ci 1978 uncertain usage
Heads are confirmed at # 3973487 or a 350ci head from 71 or 72
Distributor is confirmed at # 1111438 which is a 68 only 327ci 350HP
Can a 327 distributor be used with a 350 engine?
If not than the only 327 block is 3914678 which is the right year for my car.
Or maybe the distributor band is not what the distributor is? In that case can 350 heads be used with a 327 block? I would think not.
??????????
3914678 327ci 1968
3932388 350ci 1969
3956618 350ci 1969
3970010 - very, very common 69-80
376450 350ci 1978 uncertain usage
Heads are confirmed at # 3973487 or a 350ci head from 71 or 72
Distributor is confirmed at # 1111438 which is a 68 only 327ci 350HP
Can a 327 distributor be used with a 350 engine?
If not than the only 327 block is 3914678 which is the right year for my car.
Or maybe the distributor band is not what the distributor is? In that case can 350 heads be used with a 327 block? I would think not.
??????????
Melting Slicks
Joined: Sep 2006
Posts: 3,382
Likes: 2,605
From: Burning Jet-A
Alan,
Distrib will work in any SB,
Heads I think work better on a 350, but not positive. I think due to the "TBC" stamping, you have a better idea of what you have than the milled off casting numbers.
Distrib will work in any SB,
Heads I think work better on a 350, but not positive. I think due to the "TBC" stamping, you have a better idea of what you have than the milled off casting numbers.
