I have a small block with casting number 3932388 Mortec says 327, most everyone else says 350. How do I know without taking it apart??

According to a book I have, that cast number shows for a 350, 2-bolt main, 68-74 chevelle, camaro, nova, monte carlo. And also was used for 69-76 pickup trucks. The 327 towards the end, shows either a 3932386 (68-69 chevelle, camaro, nova) or a 3933180 (68-69 chevelle, camaro, nova, truck)

post the letters back that should be on the end of the long VIN number string that should be on the little deck pad above the top water pump bolt and we will try to decode it. No VIN b/c it's been decked, you will need to pull a head to know for sure.

pdq67

You can measure the stoke by placing a slightly bent rod (Coat Hanger) through the spark hole and measure the difference from the top of the piston at TDC and BDC. 3.25" for a 327cu and 3.5" for a 350ci. You require all plugs out, one person turning the crank and the other person holding the Coat Hanger on the same position on the piston top.

One thing to consider is that most 327's had the smaller thin 6.75" and thicker 7.25" damper compared to the 350's 8" damper. If a 327 got the large thick damper it was either a Marine Engine or put on by someone for Road Racing.

I personally use the thick 8" damper for my SBC's and use a thick 7.25" damper on my BBC's - I don't know why but it's just something I do after all these years - LOL

I thought a 350 had a stroke of 3.480.

Look at the but end of the crank. If it's shaped like a mushroom, then 327.
If it's squared on both extremes then 350.

I thought a 350 had a stroke of 3.480.

It does, but using the rod in the cylinder method and a tape measure, I doubt you will see .020" difference.

The Date code off the block, may tell a lot also. If it was cast after 1969 it is a 350. 327's were not built after '69. Also that block is a medium journal, 4" bore block that can be made into a 327 or a 350 just by changing the crankshaft ! (rods and pistons must be changed also). The 302 is also made from a 4" bore block.

Number Locations:

http://i263.photobucket.com/albums/ii152/tjs69_photos/location%20of%20engine%20numbers/endinedetail1.jpg

It does, but using the rod in the cylinder method and a tape measure, I doubt you will see .020" difference.


I thought it would be more like .250" or 1/4", surely measureable????

3932388 block was more widely used in 69 than first thought. CRG has some info. on it that I would trust alot more than other sites.
It is virtually the same block as 3932386 too. Used for many engine build ups. Not rare at all as some sites make you want to believe. :)

I forgot about the crank flange fan differences.

If you can see it??

Heck, I would pull a head and be done w/ it!

pdq67

Why pull a head? He needs to know the stroke not the bore. I agree with looking at the flywheel flange on the crank.

Look at the but end of the crank. If it's shaped like a mushroom, then 327.
If it's squared on both extremes then 350.

Is there a good pic of this somewhere? I'd apperciate it......

Never mind, found one!

Listen to Melrose-crank flanges don't lie.One notch it's a 327,two notches a 350.

... If it was cast after 1969 it is a 350. 327's were not built after '69.

In the words of the late Mr. Wayne "now that ain't entirely true' :)
327's were produced into the early 70's for truck, industrial and marine applications.
Fitted replacement block assemblies were also available from dealers for warranty work to cover the remaider of 5/50 policy in effect on these cars.

Never mind, found one!

John,
Please post it up- I can't find a good photo anywhere!
Also would be good to have 350 and 302 photos if anybody has that. :thumbsup: