318 compression question

[furiousgeorge]

I've got an '82 318 I'm planning on trying the 400 hp build on, it's still running and in the '82 Ram wrapper. I did a compression test on it, and found the outter 4 cylinders (1,2,7,8) to be between 130 - 135, but the center 4 (3,4,5,6) down, 4 and 6 105 and 110, 3 and 5 both around 115. I find it hard to believe that both head gaskets would blow out in the same spot on both sides. It starts, runs and drives ok, doesn't really use oil, coolant goes down but the water pump is worn out and leaking out the seep hole. Is this just a crazy coincedance? Or something els?
Thanks!

 

[rumblefish360]

It's shot out, time for a rebuild. It's 29 years old & Tired!

 

[furiousgeorge]

A complete rebuild is the plan, is it that the heads are warped? We're in the middle of a move, so I can't just tear it down yet, just need an idea what I need to machine/replace.
Thanks

 

[rumblefish360]

I doubt the headsa are warped, there iron and will rarely ever do that. Again, it's a 29 year old engine, hello! Tired!

The exact machine work needed will be dictated when you tear it down.

 

[Wheel Chock]

Without a leakdown test there's no real way to determine the problem, but what does it matter? I'm with Rumblefish, it's a tired old engine in need of a rebuild. I wouldn't worry about those heads because if you're aiming for 400 hp, you won't be using them anyway.

 

[caferacerx]

not unusual readings for an old high millage engine, normal wear I would say nothing to worry about, just means the rings and valves are not sealing as well as they should, you can still drive it that way for a while