L31 daily driver rebuild

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Orpedcrow

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I wanted to start another thread outside of my main build thread because I know I’ll have more questions. This is not necessarily a “budget build” but I want to spend my money wisely. I want a reliable daily driver that’s quiet-ish and smooth mostly highway cruising. No towing, and I don’t want to rebuild or replace my current 4l60e.

I’m rebuilding the engine in my truck (97 c1500 l31). I’ve thought about just slapping rings and bearings in it but I think it’s a little past that.

Ill preface by saying I am doing all the assembly in each instance.


It’s $179 difference between having my machinist do all the accompanying work on my factory bottom end ( that includes balancing but not including Mallory metal if needed) and just having him do the block prep and me buying a rotating assembly from SWP.

Machinist would use all factory parts, engine tech bearings and rings, KB or sealed power OE pistons. My 2 bolt block .040 over.

SWP includes Scat crank and rods. Weisco pistons, Hastings rings and king bearings

Or for another $676 I can buy the SWP short block kit that includes a seasoned 4bolt block .030 over making it an $855 dollar difference between having my machinist do everything and buying all new.

I don’t know if I could find a 4 bolt block AND have all the machine work done to it for under $1000



Thoughts and constructive criticism welcomed.
 
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Orpedcrow

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Here’s a link to my trucks build thread

Thread 'Teal daily driven farm truck.'
https://www.gmt400.com/threads/teal-daily-driven-farm-truck.59676/

And some pictures of the torn down engine. And some measurements.
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Edit: pictured cylinder (#6) is AFTER about 100 passes with a 3 stone hone.
 
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L31MaxExpress

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Something like this would make an excellent driver. $855 for a machined and preaped 4 bolt block is worth it provided it is done correctly and gauranteed as such, IMO.

 

L31MaxExpress

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$45 more is well worth a 6" rod 383 vs 5.7" rod 350. Just get the larger -24cc relief pistons if you plan to run it on 87 octane with iron heads.

 

Orpedcrow

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I would prefer 87, I’m also looking at either the AFR enforcers or SWP house brand heads. I haven’t taken mine apart yet to see what kind of shape the valves and seats are in. If the need a full valve job I’ll just replace them.
 

Orpedcrow

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The GM marine cam 94666492 is what I’ll put in it too. My cam had to be slide hammered out…
 

Orpedcrow

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The longer rod has less side loading Which would increase longevity by decreasing tapering of the cylinder wall?
 

Orpedcrow

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I guess I’m under the impression that the 383 is this torque monster that’s going to grenade my transmission the first time I go to pass someone on the highway :33:
 
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