The actual horse power is probably only 35 to 40more than the stock unit. Stock is rated at 220 hp, I had a similar motor with dual mags, 11:1 compression(approx), 650 holley 4 barrel. The benefits are, in my opinion, more complete burn and quicker response. Just run the engine with one mag and listen to it, then kick in the other mag a notice the difference. Also, two is better than one if something breaks. You are also better off running AVGAS if you can find it and afford it. It will make the engine run better and cooler. Hope this helps
