Newbie here

[Pstath]

Hello dai community. Reading through the forum I noticed I never uploaded an intro here. So here we go.

I recently got the little sirion. It’s the Awd version with the k3-ve2 engine. I read that it’s called GTti outside Europe, idk if I’m mistaken, anyway it’s the Sirion AWD sport m111 that produces 102hp. The car was in good condition when I got it, no rust etc. The interior was awful tho, so I removed everything, from all the 4 seats down to the carpet (or whatever it’s called), all the plastics etc. The interior is now as clean as it gets.

Now to the good stuff. After some research and the help of @Granger and @Mr_Gormsby I got the Siberian bushes for my rear suspension. Car is now rock steady, but of course it has some more vibrations. I’m planning on replacing the rear springs with harder cause the car hits the bump stops when I have 1 or 2 persons sitting in the back, and for better handling.

I really like the Awd drivetrain and I want to build upon it (in the long term). I’m not planning to race or anything. I just want a reliable, small but really fast daily driver. I will be more than happy if I manage to get 160 or 170hp from that car but here are the questions about that:

As I was reading here I came to the conclusion that the k3-ve2 is not a tuning friendly engine cause of the high compression etc. So first question is if that conclusion is correct? From my pov i will never get more that 140hp from that engine, even in my wildest dreams. So the idea of swapping the engine is here. But there it comes another question, what engine will I put in the Sirion?

Transmission is another thing I was thinking of. (It has the 5-speed manual transmission) I’ve read here in the forum that the Awd transmission is not that great and will break apart if I add a powerful engine. So I was thinking of a rebuild. Found some guys that rebuild gearboxes for tuned cars, but is it worth it?

And lastly is the Awd. Will it keep going if I have a 160-170hp engine? Or I’ll be searching where it went after a downshift

(Disclaimer: obviously I’m not a mechanic, just an enthusiast that loves cars for years now)

[Mr_Gormsby]

manual or auto?

[Pstath]

Forgot to mention that, my bad. It’s 5-speed manual luckily.

[Mr_Gormsby]

The AWD part is a funny jackshaft arrangement on the ones I’ve seen. Part time AWD and not a lot that can be done with the existing unit. Use it as it is and enjoy without looking for gobs of power. Personally I’d go for a super light flywheel and do other things to increase responsiveness. One of the things that halted my tinkering was the realisation that I needed to move away from a factory gearbox and to something like a Sadev gearbox. The other possibility is to do a full Toyota drivetrain, but you might have to pioneer things yourself.

[Pstath]

Got it. Thanks a lot for your support!

[Granger]

Yeah, As per @Mr_Gormsby - the limiting factor will be the stock gearbox.

You can get a compact motorsport gearset which I understand are much stronger, but purchase, shipping and installation will cost you approx 4k Euro. You’ll also need an LSD unless you want to sit there with your tuned engine and 4000 Euro gearbox with the front wheels spinning and you going nowhere. < Controversial opinion alert> The LSD will let you put the power down, but will make the car less pleasant to drive. < /Controversial opinion alert>

So factor in another 500-1000 Euro for the LSD at a guess.

Or look at a Sadev or Quaife sequential gearbox which are truly things of beauty but start (!) at about 10,000 Euro based on some cursory Googling. Then you need driveshaft and suspension work…

I don’t want to rain on your parade, but with the sums of money and work involved, why not just buy a fast, tunable, 4wd car to begin with? Or enjoy the Daihatsu for what it is. They can be made to be excellent handling cars for not a lot, and parts are easy to change. You’ve seen the improvement that the bushings provide, add in a set of dampers and some stiffer rear springs, some Ultra Racing subframe braces, some Nankang NS2R tyres and you’ll out-handle a lot of much more expensive machinery - for a fraction of what the engine tuning and gearbox upgrades will cost. Even with ‘just’ 102 bhp.

Fun cars handle well. Having a powerful engine in a car that can’t put the power down isn’t fun.

[Granger]

Oh, sorry - one more thing!

I have the same engine as you, but with performance cams and giving approx 110bhp. The brakes are frankly marginal at best. Adding 60-90bhp into the mix and being able to transmit it to the road will result in major, uneconomic-to-repair damage to your underpants on a regular basis!

You would definitely need to look at significant brake upgrades as well

[Pstath]

Welp, I thank everyone for the great advice and help. As everyone of you said, I will be enjoying the car for what it is now.

I will for sure add some stiffer rear springs, of course wider wheels and I will look into making it lighter (any ideas on that will be more than welcome, I don’t want to remove the rear seats cause I want it as daily tho). Maybe a better filter and a better exhaust. Maybe even a remap of the ECU, and that’s all I will do for the car.

[Granger]

I’m not saying don’t do it, but you need to look at it holistically and that won’t be cheap.

I’d say have a look at some of the Malasian sites for chassis tuning stuff. I had success with a rear sway bar from here: https://www.ultraracing.my/products/?s=&wpce_search=252830&post_type=product

The Perodua Myvi is close enough to an M300 Sirion, there is a chap on here who races an M100 in Chile who got the full chassis brace setup and spoke highly of it.

If you look at the intake side, its really easy to swap to a cone filter. The throttle body has a right angle elbow that you can fit a 51mm pipe to, then fit a cone filter to the other end and locate it somewhere that it gets cooler air. The standard setup goes right over the cylinderhead and while it draws in cool air, it heats it up before it gets to the throttle body. You will need to fit an air intake temp sensor, but they’re cheap on aliexpress. You’ll need to drill a hole and fit a rubber bung - I’ll get a pic of what i had fitted to give a better idea. Its easy to do though and will add a bit of power and intake noise.

rear springs and dampers are easy to do, lift the car up and unbolt the dampers and the springs just pull out.

weight reduction wise, the thing you’ll find is that 70% of the weight is ahead of the A-pillar. I have a tilting lift and literally can’t get it far enough forward on the car to lift the nose without having to put ballast in the boot. The whole car weighs about 700kg and I’d suggest that 300kg of that is in the engine and gearbox. Add in the front subframe, steering and whatnot and they are massively nose heavy. Weight reduction could be achieved by simple things like taking the spare wheel out and putting some tyre gloop in the glovebox (30kg saved?) but really its at the wrong end. There isn’t a lot that can be removed from the front end without majorly inconveniencing yourself!

Wheels are easy - 4x100 14 or 15 inch, 5-6j and ET34-40 should all be OK I think? MX5 wheels fit so there is a massive choice. Centre bore is 56.1mm IIRC?

Exhaust - I speak from experience! a cat-back 2" stainless system is nice, but GET THEM TO PUT AT LEAST ONE BIG, OR TWO SMALLER RESONATORS IN! The K3-VE2 is incredibly loud with an aftermarket system. I learned this the hard way. Mine was built with no resonator and was deafening, I took it back and had them put a small resonator in, but it was still loud. I have a muffler now which calms it down enough, but isn’t ideal. I will get the smaller resonator replaced with a bigger one soon because the muffler interrupts the exhaust exiting cleanly and reduces how responsive the engine is.

The ECUs are ‘locked’ so they can’t be remapped, you’d need to have an aftermarket ECU programmed and the engine tuned. Its do-able but looks like a lot of work for someone who really knows what they’re doing!

A worthwhile upgrade would be lightening the flywheel as others have said - you’d have to pull the front off the car, lift the engine and gearbox out, split them and then unbolt the flywheel for maching. It sounds a bit daunting but is easy to do. You can take the opportunity to replace the clutch - either with a new stock one, or a performance Exedy or Black Diamond:

https://www.dcperformance.co.uk/cheap/2011376/daihatsu/black-diamond-stage-2-kevlar-clutch-kits/bdc1373kvr.html

[Pstath]

Thank you very much! Great ideas, thanks for taking the time to write everything, I really appreciate it!

[TPG]

I agree with everything @Granger has said - including the LSD making it less pleasant to drive on the street.

In terms of lightness - without simply gutting the interior of all unnecessary parts…

• Do you have Air-con? If so, do you need it? Remove it if you dont need/want it.
• Rear tyre removed and replaced with a can or two of ‘goo’
• Relocate battery rearward and choose a lighter battery
• Wheels, choose lightest possible
• Carbon Bonnet - pricey from Japan
• Exhaust - replace with Stainless Steel
• Replace front seats with lighter ones
• Remove rear wiper assembly if not needed
• Windows from glass to plexiglass - perhaps just rear hatch if you’re really that keen

[Granger]

I’ll create this as a how-to as well, but here is how I fitted a cone filter for (a tiny bit) more power and better induction noise. Everything you see in this guide was bought from Aliexpress and total spend was approx £30/40 Euro.

I bought a universal cone filter and a 200mm, flared bit of aluminium tube with a 51mm inner diameter. I also bought a pack of rubber grommets and a generic intake temperature sensor like this:

https://www.aliexpress.com/item/1005004446285451.html

(big spender, me!)

Parts duly arrived and I fitted the cone to the ali pipe

You need to drill a 14mm hole in the ali pipe to fit the temp sensor into

Then fit a suitable sized rubber grommet

A bit of silicone grease helps here. Then poke the temp sensor into the grommet. The grommet allows the sensor to sit securely in the hole. You could just glue it in I suppose?

Next up is fitting it. Behold an engine bay with standard intake stuff. Note that the intake draws air from behind the left headlight, across the (hot) cylinderhead, through the airbox (left of the battery), round 180 degrees and then into the throttle body

Take of the cover and undo the 1x 10mm bolt holding the airbox on. Carefully unplug the intake temp sensor wiring!

push-fit the ali pipe into the rubberised stub off the throttle body elbow

And plug in the air intake temp sensor connector on the wiring loom to the sensor itself

and TA-DAH, done!

This is the lazy way, and the filter is 100% not optimally situated. It’ll be warm there, but you could section it off from the engine block with something, or use a mushroom filter which will be physically smaller than the cone I have and so more easily moved around the engine bay.

cost breakdown:

Cone filter kit - £12
Pipe - £6
Sensor - £4
Grommets (more than you will ever need) - £3

plus a bit of postage. A mushroom filter would be cheaper than the cone, and you could buy just the one grommet instead of a giant box of them like I did!

[Pstath]

Nice! Great guide! I will probably make the pipe longer and fit it in the front of the car, where it will take fresh “cold” air.

[DaleJeffree]

Extractors and fit an aftermarket catalytic converter further down the exhaust. The factory manifold is a massive heat soaked mass in your engine bay.
You can manage the heat from extractors with either ceramic coating (the optimum solution) or header heat wrapping.