Agreed. I've read a LOT of threads where people were looking for big power from the EJ NA, and I don't know if anyone ever did it (except this one-off project that was more than your whole budget just in the engine, and the project hasn't been updated since the first dyno run...might have blown up for all I know). Looking for more power out of a non Subaru setup is going to add a lot of cost as well, and you're on your own. I don't even think I'd rely on people who have already done it here, no matter how much they would like to help. Life gets in the way, and you never know when you'll lose your support.

If I were building this as a strict budget build to have something that would scoot around and be fun, I'd follow fill with the 2.5 NA, and keep it as light as possible. No sound, no climate control, etc.

A guy put together a bunch of power to weight ratios here
https://docs.google.com/spreadsheets...03I/edit#gid=0
The numbers are calculated backwards from what I'm used to (literally power to weight, vs my preferred lb/hp) but you can do the math and find cars like the 350z, Rx7, WRX STI, GTO, 5.7 Challenger etc all in that 10-11 lb/hp. Not bad compared to NA, but it really is a lot of work when you get down to it. After all, you could buy some of these cars salvage title and get back in working order for your budget. Then you have a car with a stereo, air bags, etc. It will have about as much market value as the kit car, judging from people who have sold them so far.

Don't underestimate the price creep of going off script with these. It will smash your budget REAL quick.

For me, this project isn't worth doing if I can't surprise the hell out of someone in a corvette or some other nastiness (don't even care if I catch them, as long as they are surprised) and the only way to do that with THIS car on a BUDGET is to turbo it and be careful on the spend.

There are other kits that might take your LD9 (Caterham maybe? LoCost variants?) but I can't be sure. They just don't look as nice (IMO). YMMV. Best of luck.