Engine swap

Hi all I’m new here I live in Melbourne and drive a 2005 sirion I. Looking and doing a engine swap but don’t no where to start or what ever bean done

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Hi Joe and welcome is there a reason for an engine swap? engine died? upgrade? or something else? are you looking to keap the same engine type in the car?

Welcome. Are you doing the swap yourself?

Probably not I’ll like to know what I can put in it and is it straight forward for a mechanic would like to give it a big buff of grunt but not sure what can fit or can I only fit a 1.5

I’m looking at more power won’t to no what I can do to it iv bean making it clean looking just won’t more go

is it the 3cyl or the 4cyl. If it is 3cyl the easiest upgrade is to sell your current one and buy the gtvi Sirion. Same car bigger engine. the 4cyl is a 1.3L.

Mines the 4cly 1.3 atm

Maybe you should try extractor’s a high flow cat and a larger exhaust. I have read somewhere recently that done right can give you up to about a 6% increase and maybe some handling modifications. If you do all that and still not happy then maybe spend a lot of money and turbo it? Maybe that is even a next step before turbo to get an aftermarket ecu and get it tuned but look at something that will allow you to turbo if you decide to go that way.
I am just making some suggestion’s. We didnt get a 1.5L engine for these sirion’s in Australia so you would have to look at importing one for an engine swap that is more straight forward. If you do that then you amy end up asking why go to that expense for 200cc. another optio is see what an engine reco place that does performance can do. They are already 11:1 compression so not really worth stroking and if turbo would probably have to decompress it anyway. Thats about as much info as I can honestly give.


the 1.3 in the M301 is a 10:1 compresion. a K3-VET wil fit the m301 as well, you wil need to change over the timing chain cover from the current K3 to the K3-VET because the engine mounth is different between the K3-VET en the K3-ve in de M301. (and the wirering loom, ECU etc)


Thankyou your input is great. I was wrong on a couple of things there it seems and apologise if a bit misleading but was unintentional, I think I was getting my k3ve and k3ve2 mixed up. He would still import all of this as it wasn’t released here.

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There is the 3sz-ve the 1.5L - would no doubt need some pioneering to make work.
Or find a locally wrecked Yaris sportivo and try to take the 1.5L 1NZ-FE out of that and try to make it work.


the 3sz is a bolt in - but not big gain in power
you could rebuild your current engine with lower compression pistons and turbo it
you’ll need a better gearbox if you go for much power - so keep that in mind
or you could get a k3vet as per above
you can get a bit more punch from cam grind / extractors / throttlebody increase

depends really if you want 5% or 15% or 100% increase in power :smiley:

all of those options you could need an aftermarket computer

or here’s something a little different from common thought - but something I love to do: change gearbox ratios
There are a few ways up the mountain here
But you can commonly increase power to the wheels around 10-15% by smarting up the ratio’s in the gearbox

Alongside this you can do some smarty up mods to the engine - nothing major but just to let it breathe
While you’re at the gearbox you can put a better diff in to aid corner speed
You can also uprate the quality of the gears to make it stronger

But basically you’re changing gear ratios so its putting power to the ground more efficiently
Heaps more fun to drive with a shorter ratio gearbox too!


Thanks all iv Sean a few sweet engine bay pic of the k3 vet turbo they look sweet might c what the cost is

the 3sz is a bolt in - but not big gain in power

In a small car I wouldn’t discount the improvement. Of course, not quite like adding the K3VET or turbo current engine.

1.3L in the 2005 Sirion: 64kw and 120nm
1.5L 3sz-ve: 80kw and 141nm

That’s a decent bump in power/torque with what would presumably little tuning issues if you were able to get an ECU for it. That’s a 25% increase, instead of a possible what 5-15% indicated for intake/exhaust mods. It may also look a lot more stock than a turbo-engine (if that is of concern to the OP).

Agree though, you could look to the gearing improvements, and flow through the current engine and have a ton of fun still. Or Turbo for outright power gains.

A step-wise approach could be the intake mods on current engine to see if that is good enough. And possibly a change to the 3sz-ve later. As far as I’ve read the head on the 1.3L sirion is effectively the same. So the intake/exhaust mods can be swapped to the new engine. If, of course, you do extractors and then want a turbo, you’ve wasted some of the money on the extractors (though could recoup some via selling them).

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Sorry I meant gain for the effort

Yeah very true.
If doing it was part of the joy/fun then the effort is not really effort.
But the money and effort to get 3rd parties to do it, is not really the best option for the gain.

So a 1.5 can fit straight in with out problems just need to get the icu I could get a turbo to suit that get the work done internal set up for it thenbolt it in

Then bolt it in… Hahaha Classic

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bolt in’s are never ever bolt in’s lol

Hammer in? Gaffer tape anything not able to be held with zip ties.