NC 2.5l engine swaps ?

[Deltona]

The other upside of a 2.5 transplant is you get forged internals as opposed to cast items in the NC1 engine.

Sorry that's incorrect.

I am not sure what the internal parts are on either engine. I just hope to get more power and torque in a reliable package.

Looking at what's been posted in this thread I can tell you you're in the wrong place.

There is a FB page for the 2.5, find it and read the pinned post.
https://www.facebook.com/groups/2006740659573188/
Look on there also for 'Duratec in detail' he has a webpage too, but due to the way it's evolved it's hard work, it's out of your league, but nonetheless there are useful nuggets on there.
Here too: https://forum.miata.net/vb/forumdisplay.php?f=110 Look for Dynotronics Joe on there (he has a website too) for ECU flash and remote mapping.
Where will the donor engine come from? That's your first hurdle.

A straight swap will not see any increase in bhp, but more torque. You need to ask yourself what it is you want and where/how the car will be dríven.
The engine is designed to go in a taxi and a truck, if that kind of power delivery suits you then go for it. It forms a good basis for much more if you've got the coin. A CR bump and cams will change it dramatically, but as stock it's perfect for turboing.

Unless you can find a way around it the Lanchester shaft cassette needs to come off for clearance in the NC, this means it'll vibrate like a tractor, not much you can do about that apart from hope the soft mounts soak most of it up.

It's all out there, you just need to ditch your phone, fire up the laptop or PC and get busy for a few hours.
Or days...

[ozace]

Thankyou, I have read all I could ,most of the forum threads get off topic ,round in circles then back. Lots of what I found comes from DIYers trying to save a few bucks. The pro's make it look and sound easy.

[Deltona]

There's only one person here who can gauge your ability to use a spanner and it's not me.

[ozace]

There's only one person here who can gauge your ability to use a spanner and it's not me.

I am not doing it myself, dont have the skills or time. I have a shop to do it for me. I was looking for views from those that have done the swap for reassurance it was worth it.

[RS2000]

Nuddy, where are you??
ozace, send a pm to Nuddy as he had a 2.5L fitted last year to a track/street car. See the topic "Nuddy's NC race car"

[ozace]

Nuddy, where are you??
ozace, send a pm to Nuddy as he had a 2.5L fitted last year to a track/street car. See the topic "Nuddy's NC race car"

Thanks, I read his thread .

[ozace]

Its done, 2.5 swap, new clutch, 4.1 diff.
Just drove it back from Sydney. Sixth gear is now usable
Wow, early days but this is how the car should have come. The extra zoom zoom is very much enjoyed.

[Custardtart]

Congrats. Did you reflash the ecu or fit a new one!

[ozace]

Reflash, as a daily driver I went mild. No fancy engine bits to need anything more than a custom tune.

[ozace]

So far after 2 days of driving, it feels strong. The torque is most impressive. The engine isn't as smooth at idle as the 2lt. The sound is deeper. The shove in the backside is much improved, both from the diff swap and the extra torque. The HD clutch has a very different feel to it, the pedal is heavier than stock but not problematic just different almost like it's more connected.
The diff swap had thrown out the gears as expected, I used to cr uise in 4th at 70 to 80, now 5th.

Just lots of readjusting to do. The traction control light may very well were out the way things are going

[Custardtart]

Sounds awesome!

What did you do with the 2.0l?

[bruce]

Yes, you'd think the scrap value of a 2.0 would be similar to a 2.5.
I woulda offered it here for sale.

[ozace]

I am having the 2l block and all the old bits shipped back in case I ever want to return to stock

[bruce]

You're never going back to stock as you'd have wasted your money doing the 2.5 swap. Then it would cost the same amount to swap it back to a 2.0. Worst case you sell the car as a 2.5
A 2.0 engine with a good history (?) must be worth something to someone. You'd think the race guys would like a spare motor.

[ozace]

85000km, easy life in very good condition, that's why I am keeping it