I think i will pass along some advice on engines. Most "Arfs" have a recommended engine size printed on the outside of the box.
You may see planes that strictly say ".40" size only. It's these combos like .40-60 or .60-.90 or .90-120. it has been my experience to always go with the largest of the recommendation.
*Case in point--- Modeltech P-47 Arf has an engine rating of .60 to .90. This plane weighs in around 9lbs respectively. I cannot imagine this plane which has a wingspan of 68inches and at that weight flying well at all with a .60 inside.
*I installed a 1.08 in mine and to me is the perfect size engine. You all may go with the .90 but a 60 is definitely out. This subject can cover a wide area but my point is to consider the highest of the ratings if your wallet can swing it.

You have to consider other things...

What about balance? What about the weight? Can the airframe handle the extra power? The vibration?

Always take those things into consideration...Most of the time the larger engine is perfect, but there are a few exceptions...

While this is true in MANY (most even) cases, there are a few exceptions.

Two reviews that I did this year for example. The Pacific Aeromodels Gee Bee "Y" says it it made for a 120 - 180. I used a 150 and that was more than enough.

The same holds true for the Giant Scale Planes Spitfire MKII. They say to use a 90 - 120. I currently have an OS 91 in it, and that provides all the power you would ever need.

I find that in most cases, the planes won't fly here with the engine on the lower side of the scale. I usually use the largest at least. We are not that high in altitude, but between 3,000 and 4,000 feet, the small ones won't do it. Sometimes I way over do it, but then those are on the planes I want really over powered.

I often go with twice the minimum requirement and end up with a good performing model. Sure that does not do the trick for all but often does for me. One thing to see if you go with much larger engines is vibration. Some engines shake much more than others of the same size, even in the same brand. My YS 140 DZ shakes much less than the older 140 L. With lighter planes, vibration will make more damage since a light airframe is easy to shake.