Confused...

[SuperMazdaKart]

How bout consider something that hasn't been done already. Like the 5 cylinder turbo engine from a Focus XR5

[WASP]

Why not fit a Honda S2000 motor and box

[Jeo]

Is this just for having fun on the road or are you planning on tracking it?

What kind of $$$ figure do you have in mind?
For the price I've often heard bandied around for a rotary conversion, you could buy a really clean FC RX7; if you sell your current NA on top of that you could probably break in to the FD market. However, I completely understand that an RX7 and an R/MX5 are not that similar propositions so all the power to you if you do go ahead. If you're set on rotary goodness, I'd assume you've seen this for sale?

Ease of fitment? Stick with MX5 engines. Obviously another B6 will be the easiest option, allowing you extra money to build a fairly hardcore one. The BPs aren't that much more effort and I can certainly see the logic there.

As for what will fit, how long is a piece of string? F20Cs have been done on numerous occasions, GM V8s are supposedly surprisingly easy, SR20s, whatever the V6 in an MX6 was called, even a Jag V12 has ended up in an NA. Basically as long as you have enough money, anything is possible.

[broady]

Joe is on the money.

Honestly, you can get a shitload of power out of the BP, turbocharged or supercharged, so unless you want to be unique or have some other requirements and deep pockets then.

Only the B6 will be a direct bolt in, but a BP will go in without too much fuss. There are kits available for the 1.6 -> 1.8 conversion.

[Mr Morlock]

For a trained mechanic with access to all facilities these jobs are challenges. Getting the vehicle certified is not easy. If you have to pay someone to do this you might as well buy a paper shredder as it will churn thru cash. There is a rotary expert on the forum ( ORX)
If you just want power - what else would be the motive- then turboing as noted already provides heaps of KW. I do not think re engineering cars should be underestimated. Bigger heavier engines are not engineered for MX5's and would in many ways spoil the car.

[broady]

For a trained mechanic with access to all facilities these jobs are challenges. Getting the vehicle certified is not easy. If you have to pay someone to do this you might as well buy a paper shredder as it will churn thru cash. There is a rotary expert on the forum ( ORX)
If you just want power - what else would be the motive- then turboing as noted already provides heaps of KW. I do not think re engineering cars should be underestimated. Bigger heavier engines are not engineered for MX5's and would in many ways spoil the car.

Yup, putting in a 1.8 shouldn't be too hard to engineer, you'd need 1.8 brakes etc to go with the engine

[Jeo]

Yup, putting in a 1.8 shouldn't be too hard to engineer, you'd need 1.8 brakes etc to go with the engine

Even easier than that. Was a simple engine number change for mine I believe.
No need to upgrade anything else, although it certainly wouldn't hurt.

[Mr Morlock]

considering that a rotary, a S2000 and a Focus were mentioned these require re engineering and the question was "Also, what easy to fit engines will also fit". Apart from an MX5 engine the rest become a money pit.

[Jeo]

B6 = 1.6
BP = 1.8
Obviously different versions of both existed throughout the years.

Not sure of any specific strengths or weaknesses of either sorry.

The engine in the Familia/tx3 turbo was a B6T, but I think there was something about the manifold not fitting that stopped it from being used? The engine of course is still a good source for relatively cheap, stronger than stock parts.

[bruce]

Consider your budget before anything else.
Rota1300t just sold a nice turbo'd motor for a very good price of $3500...