327 4-bolt main How rare?

[Tim Christian]

I found a 327 4-bolt main all I have ever seen is 2-bolt mains is this rare or special????? Any info????? Thanks

[Pyrotechnic]

If it's a large journal 327 crank, it can be put into a 4 bolt main 350 block. They both share the same bore size.

[cooters]

i have never heard of a 4 bolt 327 and on mortec website it does not show one either. Someone may have made a 2 bolt to a 4 bolt. Are the outer bolts splayed (angled)?

[kaycee]

I talked to a well known machinest about the rare 4 bolt block a yr ago and he said no such thing.Like the others mentioned above some one splayed it or used a 350 block.That is what I was told and I myself have not ever seen a true 327 4 bolt.

[VetteVet]

3955270 427 2-Bolt or 4-Bolt
3955272 396 2-Bolt or 4-Bolt
3956618 302 or 327 or 350 2-Bolt or 4-Bolt
3956632 307 2-Bolt
3963512 427 or 454 2-Bolt or 4-Bolt
3969854

I found this casting number on a couple of websites. I read it as three possibilities for a two or four bolt main. Check your block casting number.

[RM72chevy]

I just seen a 4 bolt 327 when I picked up my block yesterday, fact the guy had 3 of them but not sure if all three where 4 bolt. Dood had a chit load of old 60's to 70's blocks & heads, also seen some old fuel heads for 300.00 and he asking 200.00 for the 327 blocks (bare)

[RM72chevy]

My father retired from Chevy V8 plant in Flint Michigan, I'll give him a call and see what info I can get from him.

[shadetree]

A board member built a 327 4 bolt for his truck, several years back,,,The engine was from an old combine.

[68c10owner]

Originally Posted by VetteVet

3955270 427 2-Bolt or 4-Bolt
3955272 396 2-Bolt or 4-Bolt
3956618 302 or 327 or 350 2-Bolt or 4-Bolt
3956632 307 2-Bolt
3963512 427 or 454 2-Bolt or 4-Bolt
3969854

I found this casting number on a couple of websites. I read it as three possibilities for a two or four bolt main. Check your block casting number.

They also list the common 350 block 3970010 as being 2 bolt or 4 bolt. most I`ve seen were 4 bolt but some were 2 bolts. it also says it was used for the 302 and I think 327. They just used the same block since the bore was the same but it doensn`t mean that a 4 bolt main 327 exists. From what I have found it doesn`t exsist but then I keep hearing about industrial 327`s being 4 bolt main but I question that as well.

[jsbgump]

They never made a 327 4 bolt main block. You can make one with a large journal 327 crank in a 4 bolt 350 block due to the same bore that they have.

[BIGCHEVYMAN]

Yes they did make a 327 4 bolt main. I owned one about 12 years ago. I bought a 68 lwb rust bucket and the guy i bought it from said that the motor ran great but it smoked when first started but the engine was supposed to have came out of a 65 vette.
I said yeah right and bought the truck anyway because i needed some other parts off it. So i got the thing home running on 3 or 4 cylinders and then i opened the hood and started replacing the plug withe that the mice had ate into and it ran MUCH better. after i scrapped the greese of the head i seen the camel humps and thought i should look a little deeper then i removed the valve cover and found the 461x casting on the head and then next i ran the numbers on the block and it came up to be a 327.
I pulled the engine a few weeks later and sat it in the barn for a few years until i needed it and i tore it down to freshen it up and found that it was a 4 bolt main. That is the only 327 4 bolt main i even seen but with the 461x heads. It was a strong running motor that i never should have sold.

[68c10owner]

Originally Posted by BIGCHEVYMAN

Yes they did make a 327 4 bolt main. I owned one about 12 years ago. I bought a 68 lwb rust bucket and the guy i bought it from said that the motor ran great but it smoked when first started but the engine was supposed to have came out of a 65 vette.
I said yeah right and bought the truck anyway because i needed some other parts off it. So i got the thing home running on 3 or 4 cylinders and then i opened the hood and started replacing the plug withe that the mice had ate into and it ran MUCH better. after i scrapped the greese of the head i seen the camel humps and thought i should look a little deeper then i removed the valve cover and found the 461x casting on the head and then next i ran the numbers on the block and it came up to be a 327.
I pulled the engine a few weeks later and sat it in the barn for a few years until i needed it and i tore it down to freshen it up and found that it was a 4 bolt main. That is the only 327 4 bolt main i even seen but with the 461x heads. It was a strong running motor that i never should have sold.

What were the numbers on the block? the 461X heads were definately from a early motor as the 1968 motors had acc. holes.

[RM72chevy]

I spoke to my father. He worked at Chevy v8 plant for years out of Flint Michigan, He stated GM did indeed produce the 327 4 bolt mains, they were used in Truck applications. I asked him if they were rare, he stated they didn't produce as many as the 350's.

[jamesroy9289]

They used the 4 bolt mains in combines,trucks,and pickups, the two bolt mains were in the cars at that time, before the late 70's it didn't matter if it was 327 or 350's.

[manimal]

I have worked in Machine shops since I was 17 and have NEVER seen a 4bolt 327. They are easy to BUILD using a lrg journal steel crank or a 307 cast crank and 350 4bolt block.
Plus EVERY book I have ever read states that Chevy NEVER made a 4 bolt main 327. A 327 from a '65 vette would have been a small journal motor, and I know for a fact that a 4bolt small journal anything was ever made available to the public. Even the first "DZ" 302 camaro motors were small journal 2 bolt main blocks. The stamping on the front pad can be restamped. I know someone PERSONALLY that does it for Corvettes. Good Luck
-Lance

[lurch115]

Originally Posted by shadetree

A board member built a 327 4 bolt for his truck, several years back,,,The engine was from an old combine.

i have an old 327 out of a Massey Combine...maybe i should pull the pan before i sell it!!

[BIGCHEVYMAN]

well i must have owned one of those motors that were not avaliable to the public.
i sold it to a vette dealer here locally and he wanted it for a 65 vette restoration.
I wish i had the casting number still, that was a long time ago.

[manimal]

I have personally had SEVERAL L-79 327's from vettes,chevelles, and the RARE chevy II's. That was chevy's HOT 327. NONE of them were 4bolt mains. I have had a '67 DZ 302 block also 2bolt main.
I dont want to get into a pi$$in contest here,just saying I have NEVER seen one.
-Lance

[swb85]

I've never seen one either, and everything I've heard/seen/read says that a 4 bolt 327 doesn't exist and was never produced by GM.

[Chevymaster461]

Hope this thread ain't dead mabey breath some life back in to it ....
It seems people don't know about 327 4 bolt mains this is what I know for fact
I have a 1967 all original factory 327 4 bolt main large journal 4 barrel carb ... It came from the factory like this the trucks been in my family since 68 .. But then again my truck was custom order from factory... But yes it rolled out of Fremont ca as this block an options
All number matching frame ,cab ,spid , motor ,trans an rear



1967 CST C20

[chevybuldr]

Curious what is the casting number on the block and engine prefix code.

[crazy longhorn]

Originally Posted by Chevymaster461

Hope this thread ain't dead mabey breath some life back in to it ....
It seems people don't know about 327 4 bolt mains this is what I know for fact
I have a 1967 all original factory 327 4 bolt main large journal 4 barrel carb ... It came from the factory like this the trucks been in my family since 68 .. But then again my truck was custom order from factory... But yes it rolled out of Fremont ca as this block an options
All number matching frame ,cab ,spid , motor ,trans an rear



1967 CST C20

67would have been a SJ motor....the LJ, came in 68....none that I have seen came with 4 bolt mains, in a 327. I have heard that a Combine, or industrial engine could be 4 bolt on the mains, but I have not seen it for myself? I have heard it said that GM was playing with parts in 67, & there may be some mid yr SJ 350 engines....I have not seen it, still hearsay to me? Just my thoughts, the casting numbers, sometimes covered many yrs....when you are playing with a 40+ yr old truck....who knows what the last 12 owners did to it? Fruit for thought.....longhorn

[Chevymaster461]

Originally Posted by crazy longhorn

67would have been a SJ motor....the LJ, came in 68....none that I have seen came with 4 bolt mains, in a 327. I have heard that a Combine, or industrial engine could be 4 bolt on the mains, but I have not seen it for myself? I have heard it said that GM was playing with parts in 67, & there may be some mid yr SJ 350 engines....I have not seen it, still hearsay to me? Just my thoughts, the casting numbers, sometimes covered many yrs....when you are playing with a 40+ yr old truck....who knows what the last 12 owners did to it? Fruit for thought.....longhorn

Haha 12 owners no I'm 2nd owner my great uncle that past away bought it in 68 ... He was Really cheap I know every thing that was done to that truck an it wasn't much ... It's cast number is gm 3892657

[crazy longhorn]

Originally Posted by Chevymaster461

Haha 12 owners no I'm 2nd owner my great uncle that past away bought it in 68 ... He was Really cheap I know every thing that was done to that truck an it wasn't much ... It's cast number is gm 3892657

I did not say wont, or cant be.....can you dig up the date code, & the stamping on front? Pass side front on the stamp.... longhorn

[Chevymaster461]

Originally Posted by crazy longhorn

I did not say wont, or cant be.....can you dig up the date code, & the stamping on front? Pass side front on the stamp.... longhorn

Will do when I get home on next Monday..
But have casting number #gm 3892657 lol I already said cast number