Repop or not

How to determine

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ixtee
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Repop or not

#1

Post by ixtee »

Question is how repop 45 cylinders differ from original ones....
RUBONE
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Re: Repop or not

#2

Post by RUBONE »

ixtee wrote: Wed Oct 27, 2021 10:09 pm Question is how repop 45 cylinders differ from original ones....
Date codes, casting codes, quality of the castings.
kitabel
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Re: Repop or not

#3

Post by kitabel »

Repros are brand new
I haven't seen an NOS cylinder in 30 years

I've heard chatter that there are at least 3 sources: Poland, India, and somewhere else in Europe

The number of possible errors is huge, far $$$ to fix than sleeving a used cylinder
ixtee
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Re: Repop or not

#4

Post by ixtee »

Bought an engine with what i think are repops. No problem, the goal was the engine, and that's a nice one. Casting numbers on the cylinders are the same as on my original ones, but they're indeed brandnew so i think its repop. When they can be fitted and intake is leakfree, are there more problems to expect or are they an absolute no go....i think they look ok....if they can be fitted, why not wear m out instead of the original ones.....
kitabel
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Re: Repop or not

#5

Post by kitabel »

Possible errors (none found in original cylinders)
deck not parallel to flange
bolt pattern slightly off
intake ports do not align with manifold
nipples not sealed to ports
bore not right angled to flange
bore finish too coarse
cylinder height is wrong
guides do not align with valve seats
head bolts tapped 7/16-14'
casting has air pockets, inclusions
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