Tax refund, where to spend it?

I agree to stuff the cash in a retirement fund of some sort and maybe spend 10% of it.
If you can't save the cash up with your paycheques then your spending too much on your car.
I wish I saved more in the last 15 years so I had a cushion if the jobs all run away from North america

To those of you who have actually helped with my question thank you, and I appreciate your input. To the others, what would you do if someone came into your shop, or up to you when you're showing your car and give you **** for YOUR CHOICES on YOUR CAR. You'd tell them that they can tell you how to build the car when their name is on the title. (I'm pretty sure there's a thread about that).
I suspect that I may know a bit more about my personal finances and whether I am responsible with them than anyone here.

If I wanted a ration of grief I'd go get it from my ex wife. I already have health insurance, homeowners insurance and car insurance. I sock away 15% of every paycheck in my savings, and already double up on my $306 monthly mortgage and stick $10 per bi-*******-weekly paycheck in a savings account for my 5 year old son and let the rule of 72 take care of it. Now, are you folks happy knowing more about my personal finances?

I do not have a $900/month car payment for some useless giant truck that I wouldn't dare to use as a truck by throwing an engine block in the bed which could scratch the paint in the bed. And even if I did, it's not the topic.

If I were to do something stupid, say ask for advice on a solid roller cam with high high lift short duration and it's to be used on the street, I'd expect to get stomped flat (and rightly so) by at least yellowrose if not others also. This crap I have been getting here for advice and reasoning behind that advice so I could make a more informed decision has been useless.

Now that we got that out of the way, can we stick to the topic? I asked a specific question for a specific reason. I do not need judgmental commentary on what I want to do with money I have earned by my labor. The judgement I am looking for is, 'go with X instead of Y + Dana 60 or Z crossmember because I used it and I have found that I would or would not do it again because of a, b, and c reasons.'

Damn.