Yet another Self-Directed IRA question

[Account Closed]

I searched the forums and found a lot of people have questions about self-directed IRAs and for good reason, they are confusing! I read through about 50 posts but did not see the answer to my situation and I was hoping someone could help. 

It basically boils down to this: 

a. I currently invest X with a partner who flips houses. He does all the work and gives me a static percentage once the house is complete. 

b. I could invest 10x with him if I used my IRA funds.

Is this do-able? Is it legal? Are there any gotchas I need to know about?

Thanks!