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Engine rebuild suggestions....


srnoncom

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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.

Brett

1974 BMW 2002 Polaris and Chamonix

1969 Chevy Chevelle

www.austinsynthetics.com

** Independent Amsoil Dealer **

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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.

'86 R65 650cc #6128390 22,000m
'64 R27 250cc #383851 18,000m
'11 FORD Transit #T058971 28,000m "Truckette"
'13 500 ABARTH #DT600282 6,666m "TAZIO"

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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.

75 2002: weber, ANSA, lowered, 14" wheels, new engine, new suspension, rust free & square.

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to the OP.....fyi......175 is not a reasonable number if you have stock pistons in mind; at least from what I know.

And be aware 175 is on the high side for a N/A m10 that is streetable....it will need compression...and otherwork..... its doable, just not w/ many stock components.

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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,

Brett

1974 BMW 2002 Polaris and Chamonix

1969 Chevy Chevelle

www.austinsynthetics.com

** Independent Amsoil Dealer **

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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

1974 BMW 2002 Polaris and Chamonix

1969 Chevy Chevelle

www.austinsynthetics.com

** Independent Amsoil Dealer **

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I don't think there is a difference USA to Euro cams.

If ya want big power you should go with an S14 crank, rods, custom pistons. Ported head and at least the 292 cam. 304 would be better. At that point you will need dual 45DCOE's or ITB's and EFI.

John

Fresh squeezed horseshoes and hand grenades

1665778

 

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one cam to rule them all- even the turbo...

(ok, well, notwithstanding the TiSA...)

90 mm bore, 9.high compression.

Some have made a 92 mm bore work, but

it's not much of a boost for your buck.

I'd have the pistons in hand before boring.

t

"I learn best through painful, expensive experience, so I feel like I've gotten my money's worth." MattL

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