Hello all,
I'm looking around for something to save up for in the next year, and I would like to make some more power in my '94 Miata. So I am playing around with the thought of a swap, or building the BP and getting a BMW tranny in the future.
So, I have found a kit in my area and it's very specific, and isn't going to sell anytime soon as the Miata community isn't very big. But is is an sr20det with an unknown brand of mounts, a 6 speed trans from an S something, ecu, and miscellaneous parts for around 3k. So all I'd probably 4-5k, and I would have a much larger variety of parts.

Or, I could build my BP for 2-3k, turbo it. And in the future go with a BMW trans swap.

I am just trying to decide on m direction for the future and your opinions.

 

Or idk k swap like a normal miata person would do. Maybe even read a few threads on here.

 

Cxracing has a kit, although there's not much I would trust out of them, the oil pan does look decent though. I've thought about using an sr20 for my slow car since I have a bit of an sr20 freak friend who I could get hooked up with a bunch of parts from. I'd also keep mine n/a because I'm lame. But as of right now that car just has a bp6d as I try to get it to run.

I would factor more than that for the cost of a swap, swaps are never nearly as cheap as you think.

The k-swap is definitely more tried and true, as well as being a more modern, better engine.

 

take your best guess at cost and triple it. trust me. you arent swapping an SR for 3-4k. If you are a pro fabricator with access to all the tools, a lift, and no job, then you might get there for 3-4k.

 

The few SR cars that have been posted for sale have all had ridiculous price tags to try and compensate for the insane amount of money the owners are losing in the process.

I don't think the SR offers anything over the K.

 

The SR definitely does not offer anything extra other than the mad tyte jdm factor. Maybe a factory turbo manifold? Either way, I wouldn't call it worth it unless you're stuck on an sr and you absolutely don't want anything else.

 

I'm not even sure the SR20 offers anything you can't get from a turbo on a built BP.

Engine swaps are a giant PITA, they always cost way more and take way longer than expected, and even then they've usually got annoying little things that aren't quite right. To overcome that PITA-ness and be worth it they need to deliver something really special at the end, and I don't think an SR20 meets that bar.

--Ian

 

Friend of mine has an SR20 Miata. He won't admit it, but I think he regrets it. Wouldn't listen to me when I begged him to just turbo the BP. Oh well.

 

The SR has the benefit of lots of aftermarket support and heaps of easy bolt-on upgrades.
Which makes life easy if the car already has one in it.



But by the time you stuff about and actually fit an SR into an MX5, you could have just custom made parts for the BP.

Plus, these days there's a lot more support/parts for the BP around.




An SR swap would have made sense 10-15 years ago when BP mods consisted of Powercards and 5th injectors, or if you live somewhere with weird modification rules (example, some states in Australia it used to be much easier to get an SR swap legal than to get a turbo BP legal)

 

In the world of upgrades the BP still offers very little. See k swap. See k24 cams. Then look at BP cams.

 

Decent ECUs for BPs were not hard to get, even 15 years ago.

--Ian