[70L34]

Hi folks,
I came across a (free) 1967 L79 327 short block that looks to be basically new, with less than 2000 miles on a rebuild and 0.030” over bore. I have a set of AFR 195s and a decent sized Crane hydraulic roller for it. My question is - I also have a new set of Scat rods that I had intended for another build - should I use these rods and have the rotating assembly balanced, or are the stock rods sufficient? This will be a fun street car with occasional drag racing at the local track. Thanks!

 

[H.O.Rider]

All depends on how hard you plan to beat on it. I just built an L79 and went with a lighter pistons and better rods. Doesnt mean you need to. Just might give you some piece of mind…

 

[BillK]

Are the Scat rods small journal ? I would probably lean towards using them if you are going to run it fairly hard at times. By the time you buy a set or ARP bolts and have the stock rods resized you will probably be close to the price of the Scat rods. Also depends on what is in the engine now. If it has press fit pistons and rods I would probably leave them alone.

 

[68Chevele]

It depends on what you like to use, I have heard people say GM rods are junk and the same for Scat rods. Me so far I have used mostly GM rods and have not had one failure in 40 years of building engines. Like BillK said, by the time you get done putting bolts in those rods you might as well used Scat or Eagle rods unless that L-79 rod is a small journal rod.

 

[Bob Tiley]

Your Scat rods probably won't fit the 327 small journal crankshaft.

 

[70L34]

Thanks for the responses so far. I did confirm that the Scat rods I have are for the large journal crank, so that's no longer an option but I would consider buying new if it made sense to do so.

 

[VORTECPRO]

I ran a 327 small journal 7000 RPM often for 25,000 miles with GM rods with ARP bolts, engine still lives today.

 

[RPS]

Why spend the extra money?

 

[70L34]

Why spend the extra money?

Because I don't want it to come apart.

 

[70L34]

I ran a 327 small journal 7000 RPM often for 25,000 miles with GM rods with ARP bolts, engine still lives today.

Thanks, great info. I think I'll probably end up going this way and having the stock rods resized.

 

[VORTECPRO]

Thanks, great info. I think I'll probably end up going this way and having the stock rods resized.

Only if they are virgin rods and always ck small end for press before any work commences.

 

[cstraub]

Thanks for the responses so far. I did confirm that the Scat rods I have are for the large journal crank, so that's no longer an option but I would consider buying new if it made sense to do so.

King makes a bearing to put a larger journal rod on a small journal crank. With that large a head on a 3.25 stroke engine it will need to turn some rpm be for it starts to feel good. On the other hand a 3.25 stroke engine doesn't make a ton of piston speed. As Mark said stock rods with good bolts and polished beams worked very well for many up until the late 80's early 90's when Eagle made rods affordable to everyone.

 

[RPS]

Because I don't want it to come apart.

I just meant to use existing rods instead of new ones. Resize away! 😆

 

[70L34]

I just meant to use existing rods instead of new ones. Resize away! 😆

Sorry, I misunderstood your comment
I think the ARP bolts in the stock rods approach is the best option for me. The engine was in a 62 NCRS stocker corvette so it’s never been abused since it was rebuilt.

 

[RPS]

Right on, and you should not have to balance it either, saving more money.

 

[VORTECPRO]

Sorry, I misunderstood your comment
I think the ARP bolts in the stock rods approach is the best option for me. The engine was in a 62 NCRS stocker corvette so it’s never been abused since it was rebuilt.

Does it have 461X heads?

 

[70L34]

Does it have 461X heads?

No, it was the incorrect engine for the 62 - it's a 67 dated replacement engine that had 462 heads (which he kept).

 

[mrpaticular]

Magnaflux crank and rods before anything. I would save the scat rods. How long are they?
All crank clearances must be checked.
Any work on the crank, rods and new bolts will throw the balance off.

 

[MikeN]

In my 65 Impala, I run a 1969 vintage 2-bolt main 350 with the stock GM cast crank, stock GM rods, and cast aluminum flat-top rebuilder pistons. On top of that, I have a set of EQ heads (Vortec copies) with a Lunati 219/227 hydraulic roller cam.

I spin it to 6000 at the dragstrip, and over the last 5 years I'd say 250-300 drag passes, at least. No issues at all. With stock converter in the TH400 and stock rams horn manifolds, best ET's are 13.80 @ 99-100mph. With a 2400 stall and headers, it went a best of 13.22 @ 101.5mph.

So, the stock stuff can take a beating. All that said, the small journal 327 rods MAY not be quite as stout as my 350 rods - maybe one of our engine builders on the forum can weigh in on that. All that said, it sounds like a cool combo, good luck with it.

 

[MikeN]

By the way, I also have a complete 67 vintage 327 I bought maybe a year ago. The pad stamp indicates a 67 full size chevy with a 275hp 327 and PG, and it does have either the 461 or 462 heads still on it (I can't recall which casting number was used in 67). I'm thinking I'll retire my Impala from track duty at some point and put my 327 back in it, built to the same specs as a 65 327/300.