In your opinion do you think that the Super Tigre .40 is enough of an engine for the Hanger 9 P-51 PTS?

Super Tigre engines are great. For that plane, I'd go with their GS-.45 though. The .40 would probably fly it but the performance probably wouldn't be all that great in my opinion. Any other strong running engine in the .46 range would work well too.

I have a spare brand new super tigre .40 lying around and I was wondering if I should buy another alpha (crashed) or go with a p-51 pts. I currently fly a sportster and and sig kougar and used to fly an ugly stik (crashed). I would like to get the trainer again for fun and for friends but at the same time I want to get into war birds.

I have both a G-40 and a GS-45 - either would fit the bill nicely. The 40 is only fifty bucks... can't beat that. Just be advised that the 40 will take a bit more breaking-in than the 45.

I have the G-40 on my Voyager works just find, very good engine. Since you have one why not try it and see how it dose can always come back later and changed the engine if you feel you need more.