This summer I am faced with doing something with my 3.0. It has all the symptoms of a bad number 6 valve, the oil pressure drops almost to 0 at an idle, the clutch is bad and it is getting 13 mph. I am thinking of doing the 3.4 swap but the expense is limiting. I can buy a 3.4 from a salvage yard for $1200 but it is an automatic and I have a manual. So from what I have read things do not always match up.

So I am thinking of rebuilding the 3.0. Is it worth boring it out and if so how much is safe?

 

Not sure about boring specs myself, but only 13 mph? That is awful! I hope you are always in the emergency lane on the highways. Sorry about that, jjenks0. I could not pass it up.

 

no problem I hope to get the mph improved by next fall

 

I think you mean MPG, not MPH.

Boring does nothing for performance, even though you always hear some moron saying how he "bored" his 350 out to 383 or whatever. You might pick up 3 or 4 cubic inches with a 0.030" overbore, which does NOTHING for performance. Displacement increase comes from STROKING, which you're not doing.

Any increase in performance, power, or just plain reliability will come from the complete rebuild that usually accompanies an overbore, NOT the overbore itself.

Brian