348 rebuild

Hi gents,
Looking for some info on a possible 348 rebuild. Engine is out of car after showing 145-150 psi on compression check with one cylinder showing 130. Engine is headed to very well respected shop that will give me the news next week. I appreciate every situation is different but a couple of ballpark numbers on rebuild cost would be greatly appreciated.
Many thanks


Supporting Member 1
3500 to 6500 would most likely be a good number, but not knowing what it needs, or your intended use, this is a shot in the dark. Once they assess the engine, and give you a number, let us know. We can take it from there.


Well Known Member
Supporting Member 2
With forged parts you can get it built (not just refreshed) and done right for ball park $6500. Then you can add the external performance parts like intake/dual carbs, headers... later. But don't be affraid to waste money on high compression pistols and fancy crankshaft. Unless you are racing each weekend you will have thumb rods and a 70 454 crank machined to fit. Externally balanced.
The engine is not completely torn down yet but I am in need of at least one head. Shop found that one is cracked. Any suggestions at this point are appreciated? Will know soon if the block is a “keeper” and what direction we are going.
Many thanks
Yes the heads are 379s.
If my mechanic green lights the bottom end of the block I will be looking for a replacement head. I’m not concerned with dates.
Hi Don,
If the engine can be rebuilt I’m good with stock or a mild upgrade. Cost may give me pause and direction however.
I hope by weeks end I will have some news on the block. The 58 Impala that I’m restoring is a restomod by the way.
6 speed, center console, bucket seats and Vintage air.

Tom Kochtanek

Well Known Member
Supporting Member 10
Aha, it's from a 1958 Chevy! I might have a set of early 379s around the shop. Pretty sure they are 1958 castings.

Rather than replace that single 379 head you might consider replacing those 379s with a pair of 333 truck heads for a "budget" build. These333s can be outfitted with larger valves and other upgrades (screw in studs, mid porting, etc.)
for improved performance.

Generally you can pick up a set of bare 333s for $200 - $250 if you are persistent. I've got a few sets of those if you are interested :).

Just a thought!

Don Jacks

Well Seasoned Member
Supporting Member 3
From what he said,the cars kind of a restomod.He's gonna want some kind of performance,and that means a 333,817 or 1147 head.Tom needs to sell him a set of those 333'ss.THEN he's got something to work with.I worked up a simulation for a budget style 348 and a budget 380 last night[that 58 would really love the extra torque],and I think I have a couple of good recepies for an '"inexpensive" W engine[5,500 max.rpm]that would put some fun in that 58.
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Tom and Don,
Thanks for your suggestions. The machine shop where the block is located is swamped and behind because their washer was/is down.
No words yet on the block. So far the damage is a cracked head and a cracked exhaust manifold. I’m hoping the block isn’t also cracked.

Tom Kochtanek

Well Known Member
Supporting Member 10
Let's hope at least the block is OK. Those exhaust manifolds are likely the 2" center dumps, and you would want to think about something more "evacuative" (is that a word?) such as the 2.5" center dumps or something more "custom" (like headers).

The choices are yours, we just get to give you ideas for success. Spend your dollars as you see fit. On the other hand, I bet a lot of us would like to see Don's recipe for a "budget style 348" :).

Cheers! TomK
I got word last night that the engine has forged pistons but no further word on the condition of the block. I’m on the road for 12 days starting tomorrow and need some info from you if you have the time today. Could you please take a look and see what you have in regard to replacing my 379 head? I’m trying to get ahead of the machine shop searching if in fact the block is ok. Condition, price and a contact number/email would also be helpful.
Many thanks