I am thinking of using a magnum 52 4 stroke on a 40 sized great plains P-51. Will this work? I know many will say this in too small of an engine but I am not interested in max speed and circus trick aerobatics.I just want power for take off and good overall flying.What about a 3 blade prop?

I have always found that a 60 4-stroke is equivalent to a 40 2-stroke.
The magnum 52 4 stroke should be just fine.
I'd try the proper sized 2 blade first and if it has plenty of power then try a 3 blade prop.

Tom

I think you'd be fine

Thanks. It's always good to get another opinion. What prop would this engine take?

a 12x6

don't even think about a 3 blade prop! the 4-stroke won't make the rpm you need. besides, they only look cool on the "ramp". I made that mistake with a kit built zero and it was a good thing I had the plans After the repairs I used the right 2-blade prop and was very happy with the pulling power.
Jim

I would get a 61 four stroke engine. Perhaps the ASP FS61AR that is sold by Hobbyking in the US warehouse. It is the exact same engine as the Magnum and has the same dimensions since it is a bored out 52. The 61 will provide a more enjoyable flight experience, not to mention the 61 doesn't weigh as much (11 grams lighter).

The ASP Engine is made in China by SanYe which is where the Magnum is made also. The ASP Engines are generally cheaper than the Magnums. For example, a Magnum 91 costs $200 while the ASP 91 costs $130 and they are exactly the same. But the 52 will fly the airplane decently, the 61 will provide more power for better aerobatics and "get out of trouble" power which to me, is very important especially on a warbird.

I would also go with a .61 or bigger fourstroke. As for the prop, its a P51! You can't put a two bladed prop on that! lol.

Seriously, With proper prop selection (trial and error) I have flown plenty of three bladed props with no ill effects.

I do like the looks of the 3 blade so what size? The 2 blade would be just fine.

I agree, I use to run the Magnum 52 and still do on some, but the 61 is the same size so why not get that extra punch when you need it.

A good choice for 2 blade would be 12x6-12x8. So a nice 11x6 or 11x8 three blade would work just fine.

Originally Posted by mashp39

I do like the looks of the 3 blade so what size? The 2 blade would be just fine.

Originally Posted by Rcflyyer1

I would get a 61 four stroke engine. Perhaps the ASP FS61AR that is sold by Hobbyking in the US warehouse. It is the exact same engine as the Magnum and has the same dimensions since it is a bored out 52. The 61 will provide a more enjoyable flight experience, not to mention the 61 doesn't weigh as much (11 grams lighter).

The ASP Engine is made in China by SanYe which is where the Magnum is made also. The ASP Engines are generally cheaper than the Magnums. For example, a Magnum 91 costs $200 while the ASP 91 costs $130 and they are exactly the same. But the 52 will fly the airplane decently, the 61 will provide more power for better aerobatics and "get out of trouble" power which to me, is very important especially on a warbird.

I can vouch for the ASP 61 4 stroke. I just received mine from USA warehouse for $124 to my door. Thus far I am really impressed with this engine. It starts with one flip and runs quite well. I bought my first ASP 46 2 stroke in 1991 or 92 and it was a barn burner. Love the ASP's.

stay with the 2 blade prop...as the Mustang had a 4 blade prop...your not going to be scale with a 3 blade....2 blade will fly it better

Originally Posted by Rcflyyer1

I would get a 61 four stroke engine. Perhaps the ASP FS61AR that is sold by Hobbyking in the US warehouse.

It is the exact same engine as the Magnum and has the same dimensions since it is a bored out 52. The 61 will provide a more enjoyable flight experience, not to mention the 61 doesn't weigh as much (11 grams lighter).

The ASP Engine is made in China by SanYe which is where the Magnum is made also. The ASP Engines are generally cheaper than the Magnums. For example, a Magnum 91 costs $200 while the ASP 91 costs $130 and they are exactly the same. But the 52 will fly the airplane decently, the 61 will provide more power for better aerobatics and "get out of trouble" power which to me, is very important especially on a warbird.

Al parts are manufactured to some tolerances.

I am wondering if the Magnums might be assembled with parts closer to the center of the tolerances and the ASPs with parts further away from the tolerances centers.

The results would be a shorter life for the ASPs having the equivalent of some wear as compared to the Magnums.

There has to be a logical reason for the price difference.

Zor

"There has to be a logical reason for the price difference"

GREEEEED!!!!!