My friend has a Speed Vee 800 and was wondering if it is possible for him to turn it into a nitro. I told him that it was most likely not possible, but that I would ask around. Also, I am not very knowledgeable when it comes to boats so help me out please. Thanks.

In principle it's possible to change to a nitro engine, but I don't know how much work it will be in that hull.
Keep in mind that the hull was designed an entry level boat, I'm not sure how thw boat will handle the increased speed of an nitro outboard.

Tell your friend to break his piggy bank, these outboards aren't cheap...

Regards, Jan.