[56cheby]

ok, not sure where to start but: i bought from a neighbor the original engine (or so i thought) out of a 68 camero..it was his aunts car from new...327 210 hp....gave the engine to a speed shop to rebuild...they had a set of 194 valve double hump fuelie heads which they redid with hardened seats...they put a 350 hp cam , new pistons, etc in the car and reused the 327 crank..use middle grade pump gas..car runs strong but were having overheating problems which are now 90 % fixed...was at a car show today and an friend told me that the engine was not a 327 but was a 350..upon decipering the codes it comes out to a 74 350 from a police car....the speed shop said that this changes nothing..i have a 350 block with a 327 crank so i still have a 327....they bored it .40 over...should i be concerned or am i reading more into this than i should be...i was always told that a 350 block...the water passeges were closer to the cylinders than a 327?????? help me undo my concerns....please.....

 

[hotrodg726]

as far as the water passages are concerned there is no difference in a 68 327 block and a 74 350 block . the only difference is it is not a small journal engine the original 8 327 is a small journal enging the 350 is a large journal engine. the bummer is the cranks don't interchange and the early small journal ones are steel the majority of the large journals are cast iron cranks. as far as the average car is concerned it really makes no difference. just technical jargin to cloud the mind. I would just drive it and enjoy it :happy0030:

 

[pistoncan]

as far as the water passages are concerned there is no difference in a 68 327 block and a 74 350 block . the only difference is it is not a small journal engine the original 8 327 is a small journal enging the 350 is a large journal engine. the bummer is the cranks don't interchange and the early small journal ones are steel the majority of the large journals are cast iron cranks. as far as the average car is concerned it really makes no difference. just technical jargin to cloud the mind. I would just drive it and enjoy it :happy0030:

While I don't know all the tecnical details, Hotrod is correct. The bores are the same. The larger journal crank is an improvement, steel or iron. I have a 283 engine with a 327 crank in it in my 55 they call it a 307, goes down the road just fine. ENJOY

 

[jwmbishop]

If memeory serves me correctly (I did research on this one back in 85 when I got a 327 R\S camaro)
The 68 was the year they blended the journal sizes - the block was the same but to use up all the small journal steels they put some 327s out that were small (R\s and R\s\SS) some large (327 3speed) and resmelted anything left over after the 68 year. 69 everything was large journal.

In a number match either one worked for 68, 67 was small only and 69 was large only. So a 74 block should be a good numbers match authorized replacement.

To further complicate - I think it was 74 when they went with the new univ VIN system - prior to that a block number from one year may show up as a number in another - the three letter code would be the only difference -meaning it IS possible you do have a large journal original 68 block and it shows the same number as the 74! And if you do have a police car engine it could be three to four years past the cast date - these weren't built in the same runs as the regular engines - and when they did a run they would do enough to last awhile.

The water passages were not so much closer as core shift was more prevalent. Not to worry if you can keep her under 200 degrees - I have gone to thin wall problems boring and when you are to thin - you know it. NOTHING keeps it cool!

the 350 block is better as it has a higher nickel content than the 327 while the 327 small crank is better than the 327 large or 350 crank. But the big journal is better as there is more surface area for the oil film. So it all a trade off. You got a good combo - run it with happiness.

I love me some 327 the big bore small stroke is a nice sounding engine with its noticeably quick spin up - and fairly easy to get 400 ponies from with very few issues. If I could find a 327 stroke crank (that is not race ready - too light for the street and too darn expensive) for the one piece seal I would make that the build for my 57 when I refit her in the next couple years.

 

[56cheby]

thanks for the reassurance...the way it was explained is...the 327 crank (with large journals) was put in the 350 block so i still have a 327, just not by the numbers on the block....the builder told me, had it had a 350 crank then all the 327 pistons, etc would not have fit...i will relax and enjoy the ride...thanks for all the input, wanted to hear it from more than one person...this is a great site and have had some great advise..tri 5's forever.