307 @ .30 over = what?

[hgoodfel]

I am restoring a 75 c10 4x4 short bed.  While prepping for paint I decided to see what engine really was in the truck.  It was sold to me as a "350" and the truck has the 350 grill and the glove box said it was shipped w/a 350.  The code I have is a V0519TAO.  My understanding is that it is a K10-1500 1970 AT 307 200hp 2bbc.  This engine has a really lumpy cam and a 650 Holly 4barrel on it.  After letting the former owner know he called the guy who had the engine before he did and he was told that it was taken .30 over.

So... what do I have?  A 327 or a 315?  Outside of boat anchors... what are the redeaming qualities of a 307 SBC?  I have had 350's and 400's and am thinking about swapping this out but thought I'd ask here first.

Thanks!
Herb

[hgoodfel]

The complete code is TK V051 9TAO.  Sorry about that.  

[Blazin]

I have heard more times than I can count over the years that 307 are nothing but junk. They are not power houses stock but every one I have ever had ran & ran & ran & ran. I had one that smoked so bad every morning I would add approx half a gallon of waste oil. That thing started on the first try and never ever missed a beat in over a year of running it. I say if it runs good someone already went to the trouble of rebuilding etc. I would run it till it craps out. You say it has a lumpy cam. Does it have nut?

[1976Scottsdale]

307's are not all that popular, but they run very well and rev really fast due to their 3.25" stroke, which will come into play in a moment, versus the 350's and 305's 3.480" stroke.  What I have done in the last few days is taken the crank from a 350 that I broke and found that it was from a 307, which has the same stroke as a 327, but will fit into a 350 block.  I am going to use the crank in a 350 block and make a 332ci engine with 4 bolt mains.(327ci with a 0.030 over bore = about 332ci)

Your 0.030 over 327 should be 312-315ci, just to answer your question after my blabbing.

[Blazin]

Some of the 307 & 327 had small main jurnals like the 283. some of them had large jurnals like 305, 350, 400.

[1976Scottsdale]

I was not aware of that for 307's, I knew that the 327's up to 67 or 68 were small journal, but it makes sense.  Learn something new everyday.

[Blazin]

I have never actually seen a small journal 307 with my own two eyes, but I have been told they exist.

[roundedline]

The 307's were made after 1968 which were large journal.  I think those that say 307 cranks exist in small journal size are confusin them with the 327 cranks.  Both are actually just 3.25" stroke cranks.

Chris Lucas
www.73-87chevytrucks.com
www.captkaoscustoms.com
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