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Engine rebuild suggestions....


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I just found out that one of my cylinders has no pressure, so I'm waiting to hear the verdict on the culprit. What led to the discovery is that i purchased a 74 O2 that we thought had a blown head gasket. So I now have a rebuilt E12 head, with a european grind cam and an apparent stock lower end.

My questions are:

If the stock pistons are still good.....is it a good idea to replace just the rings, of course after honing, etc....depending on the cylinder walls.

If the cylinders are okay, and by some chance a piston needs replacing....but didn't score the wall (unlikely with this scenario)....how difficult is it to get stock pistons and is it even worth it.

If I choose to bore the cylinders, what is the largest bore that is recommended and still have long term durability....using the european grind cam, and a 32/36 carb. Looking forward I was thinking of leaning toward side draft webers, etc.

In a nutshell what I'm trying to do is get going with minimal expense, but ensuring durability until I can actually rebuild a "nice" motor. If I do need to bore the cylinders, what is the smartest step toward a motor producing approx. 175 HP in the end?

Hopefully all of this makes sense.

Thanks in advance for the assistance.


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sorry your so confused -

first you must true up the cylinders by boring or honing depending

on the amount of taper and wear - accurate machining

and measuring is required

THEN you fit pistons to fit the bores.

build what you really want now

your not returning to redo all that labor later,

so build and spend what you can afford now,

and enjoy it being complete.

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what is the smartest step toward a motor producing approx. 175 HP in the end?

I am still wondering how all these posters get to such a high HP number? Is it me or does 175 HP seem like a race engine?

I have a 100% fresh engine, 284 cam, SS valves, 1st over pistons (not high comp) Header, 002 mech dizzy, 32/36 Weber...... and I can't imagine that it produces much over 115 HP, so how would I get 60+ more HP without spending $$$$$$$$$$$$$$$$

Just wonder'n

Oh please don't ban me!!! I swear I am being as polite as I can.

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I appreciate everyone's response! What I've decided to do is....

If cylinders are only in need of honing, then replace with stock pistons (I actually found 1 SET available).

If I need to bore, then I'll go slightly larger, and keep the head as it is .... and call it good!

Thanks again,


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Update to my question.....well the engine needs rebuilding! So a quick question, I have an E12 head with european grind cam. What is the largest bore and highest compression I can run using pump gas, and preserving engine durability? While matching specs of european grind cam? Much thanks

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