It's been a while since I checked this thread. I've since dropped the Werks Collari .32 MT into my Mammoth ST. Wow!! This is one torquey motor. I don't think the top speed is any better. In fact, top speed might have dropped some. I don't own a radar gun so I don't know for sure. Plus it's still plenty fast enough for me. Off the line acceleration is tremendous and that is what I bought the engine for. I can pull a wheelie if I really try, but the Mammoth ST has a pretty long wheelbase, so it doesn't hop on every throttle squeeze like my short wheelbase S-MAXX with .21 Wasp.

If that Racer's Edge .32 is in good shape, it will be a very fun engine for bashing your Mammoth.