In the UK, the only known reasonable ship is Nicholson McLaren.
On mainland Europe, I don’t know of any engine shop which has a consistent reputation. Some of the above names have produced junk jobs.
I’ve merged several identical threads, so there is more reading further back 
In the UK, the only known reasonable ship is Nicholson McLaren.
Very surprised at this blanket statement!
While McLaren are a very good shop I have used Norvic for four engines and was completely satisfied. Would probably use Norvic again.
RobertL18C wrote:
While McLaren are a very good shop I have used Norvic for four engines and was completely satisfied. Would probably use Norvic again.
used Norvic 3 weeks ago for overhaul of a prop governor (linked to the new engine in the Comanche), even though the ole lycosaurus is still an 540 there is a difference in settings between the wide deck and the narrow deck (new engine is wide deck). Norvic knew exactly what to do and did the job in 1 day allowing for it to be done during the annual. I’d give them a 5 star rating based on that one experience.
Are all overhauls equal ?
On the US website, some shops offer :
* New Weight-matched pistons
* Weight-matched connecting rods
* Crankshaft and rotating assembly, dynamically spin-balanced
* Flow matched cylinders
Is it a thing or just vendors’ speak ?
It’s real but the manufacturer did most of that list on the engine originally, perhaps to a looser tolerance. ‘Flow matched’ cylinders would be an exception and you can probably get a bit more power if it’s done right. ‘Flow matched’ is presumably a euphemism for ported, modified outside of the TC & MM in a way that doesn’t show much visually. However I have my doubts that C.R Axtell has been reincarnated at many US aircraft engine overhaul shops.
I am told:
Any crankshaft is balanced as part of its manufacturing process, a procedure that depending on engine configuration involves adding temporary weights to achieve the correct imbalance. The necessity to rebalance might be considered after journals are ground slightly undersize at overhaul, and balancing an opposed cylinder aircraft crankshaft is relatively easy. Any automotive crankshaft balance shop could do it under A&P supervision.
A careful valve job with multi-angle ground seats probably does as much as porting. Porting is regardless being done on certified engines beyond the removal of casting flash, because that’s a fuzzy definition, but probably not to the extent of complete reshaping with epoxy added and so on. When done to a limited extent it’s hard to see visually how much material has been removed. I once had a little A-65 with cylinders overhauled by a well known shop, and it made good static rpm
Has anyone here ever had a Victor Aviation overhaul? They have a high reputation in the US but are expensive. They recommend using one of their preferred installation facilities and the only one listed in Europe is Motorflug in Baden-Baden. Has anyone ever used Motorflug for any work?
Also, I’ve been told that there is a currently a huge problem getting some parts including cylinders, especially from Continental but not limited to them. I was told by a local mechanic that timelines are up to a year or more and Continental isn’t responding any more to requests. Anyone else heard anything similar or have a contradicting experience, especially with Continental? Is this a real problem or just hearsay? If real, just Europe or USA too?
I spoke to someone who had an O200 rebuilt in the US recently. Short wait for cylinders, which were Superior, no other problems.
But it will likely depend on your engine.
