327 or 350?? confused ..

ok so I pulled a motor from a hot rod i bought a few years ago . Put it in the shop and forgot about it ..
The seller told me it was a 327 ... then a guy who knew him told me it was a 350 ... The casting is 3970010 .. and it has 2 freeze plugs ... can you help with this one ??? thanks in advance .

 

350

 

does the fact it has 2 plugs mean anything .. like 2 bolt or 4 bolt ??? wishfull thinking

 

pull the heads and measure the stroke. I have a 327 that was built using a 4 bolt 350 block

 

crankshaft # ?

 

Measure the stroke. Sorry, no easy way.

 

350 Block (high nickle content)

 

you can build a 327 using a 350 block... and the 0010s were 69 and up so (iirc) they're all already large journal cranks. Casting numbers COULD reveal what that motor possibly is, but not 100%.

My block could have either been a 350 or a DZ302 (woah!). It was a 350. Still a good motor, just not all that rare.

 

For most engines like the 350, the same block was used for 2 and 4 bolt main. So the casting # info will say "2 or 4 bolt". The most common 350 was the 3970010 block. It was used from 1969 through 1980. Made in 2, or 4 bolt, used in cars, trucks, vans, 1bbl, 2bbl and 4bbl carbs

Now it can tell if 2 or 4 bolt on some of the rare high performance engines, or over the counter engines.

Here's the list of all the small block casting #'s

CASTING#.....SIZE...YEAR...MAIN CAP BOLTS....NOTES

140029.....350...80-84...2
330817.....400...72-80...2
355909.....262.....75....2
360851.....262...75-76...2...Monza V-8
361979.....305...78-79...2
366245.....350...78-79...2
366287...................4...Bowtie, Aluminum, siamesed,
straight nodular iron main
caps, 2-piece seal, 4.00-4.150"
bores, 2.45" main journals
366299...................4...Bowtie, Aluminum, nodular
iron splayed caps, wet sump,
4.00" bore
389257.....302.....67....2
393288.....283...65-67...2
460703.....350.....78....4
460776.....305...78-79...2
460777.....305...78-79...2
460778.....305...78-79...2
471511.....267...79-82...2
3556519....283...58-61...2
3703524....265.....55....2...No oil filter
3720991....265...56-57...2
3731548....265...57......2...No side motor mounts
3731548....283...57......2...No side motor mounts
3737739....283...58-64...2
3756519....283...58-62...2
3782870....327...62-67...2
3789817....283...62-64...2
3789817....327...62-67...2
3789935....283...61-64...2
3790721....283...62-64...2...Chevy II recessed oil filter boss
3790721....327...65-66...2...Chevy II recessed oil filter boss
3791362....327...62-67...2...Chevy II recessed oil filter boss
3792563....327.....65....2
3792582....283...64-65...2
3794226....283...58-63...2
3794460....327...62-64...2
3814660....327...68-69...2
3830944....327.....63....2
3834810....283...64-66...2
3834812....283...62-63...2
3837739....283...58-62...2
3849852....283...64-68...2
3849935....283...65-67...2
3852174....327...62-64...2
3858174....327...64-66...2
3858180....327...64-67...2
3858618....350...68-76...2
3862194....283...65-67...2...Chevy II recessed oil filter boss
3862812....283...62-64...2
3892657....302.....67....2...Z-28 Camaro
3892657....327.....67....2
3892657....350.....67....2...Camaro
3896944....283.....67....2
3896948....283...66-67...2
3903352....327.....67....2
3914636....307.....68....2
3914653....307...68-73...2
3914660....327.....68....2
3914678....302.....68....2...Z-28 Camaro
3914678....327.....68....2
3914678....350.....68....2
3932371....307...69-73...2
3932373....307...68-73...2
3932386....302.....69....4...Z-28 Camaro
3932386....327.....69....2
3932386....350.....69....4
3932388....350.....69....2 or 4
3951509....400...70-71...4
3951509....400...74-80...2
3951511....400...70-71...4...Some replacement blocks had 2-bolt main caps
3956618....302.....69....4...Z-28 Camaro
3956618....327...68-69...2
3956618....350.....69....2 or 4
3956632....307.....69....2
3959512....327...62-63...2
3970010....302.....69....4...Z-28 Camaro
3970010....350...69-80...2 or 4
3970014....350...70-74...2 or 4
3970020....307...70-73...2
3970024....307...69-71...2
4715111....305.....80....2
6259425....350...69-76...2
10036033...350...........4...Goodwrenc… crate motor, 2-piece rear
seal, "Hecho en Mexico"
10051182.................2...Bowtie, non-siamesed, 3.75" bore
10051184.................4...Bowtie, non-siamesed, 4.00"-4.160" bores
10054727...350...86-up...2 or 4...one piece rear seal, some "Made in Canada"
10066036...350...........4...Goodwrenc… crate motor, 2-piece rear
seal, "Hecho en Mexico"
10066038...350.....94....4...Goodwrenc… crate motor, 2-piece rear
seal, "Hecho en Mexico"
10090511...350.....90....2...LT-5, ZR1 Vette, 375hp
10125327...350...92-up...4...Gen.II LT-1, reverse flow cooling
10125327...350...96-up...4...Gen.II LT-4, reverse flow cooling
10134996.................4...Bowtie, Aluminum, 4.125" bore
2.65" main journals
10153558...350...91-92...4...LT-5, ZR1 Vette, 375hp
10199001...350...93-95...4...LT-5, ZR1 Vette, 405hp
10243878...305...96-97...2...Vortec truck, roller cam, one-piece rear seal
10243880...350...95-99...4...Gen.I crate motor, "ZZ4", roller cam, one piece rear seal
12550592...350...97-up...crossbolted block, Gen.III, "LS1"
12559846...350...98-up...crossbolted block, Gen.III, "LS1"
12560621...350...98-up...crossbolted block, Gen.III, "LS1"
12562174...350...98-up...crossbolted block, Gen.III, "LS1"
14010201...305...80-84...2
14010202...305...80-84...2
14010203...305...80-84...2
14010207...350...80-85...2 or 4
14010209...350...80-85...4
14010280...

Please press 5 if this was of any help! Your welcome

 

Grab the suffix code stamped on the pass front deck surface and it will tell you exactly what it is. Probably be a 3 letter code.
'69 327 large journal, and 350's of that vintage could have shared the same 010 casted block. They had the same bore, but the stroke was different.

Tony

 

Even if it is a 350 ,Thats good ,Block number is 350

 

Could also be just a two letter suffix code.

 

Didn't the 327's all have the small balancer? I know the 350's all have the large one. Even if it was a 350 block, a small balancer would indicate they are utilizing something other than 350 moving parts. I used an LT1 4 bolt block when I was class racing a 305 inch motor. (.030 over with 283 crank).

 

Hi horse 327's had the eight inch balancer. Fins cast into the back of 'em. Dennis D

 

Like everyone has mentioned, the block is a very common 4" bore block, large journal. Beyond that and assuming the motor is still assembled, you can tell a 350 from a 327 by looking at the crankshaft flange. Both have a fat side and a narrow side, but the fat side on a 350 (3.48 stroke) has two flat edges about an inch long across from each other. The 327 is a full half moon on the large side with no straight edges.