My Sirion M101


#1

Hi guys,

As promised, I’m going to open this post with my project.

My car is a Daihatsu Sirion 1.3 with k3-ve2 engine, here in Chile, it’s the only model that was sold from 2000 to 2005, mine is 2004 model (I know it’s early model, it must have been stored a long time ).

Initially it was going to be my daily car but little by little it has been transformed into a daily car and some track. finally it became participating in track days at least once a month.

That’s how it was when I bought it. Unfortunately the engine was in a terrible state so had to rebuild from scratch.

Find the parts of the car was a birth !! (I don’t know if an expression like that is used in other countries) … after a lot of searching and importing some spare parts we got everything but one … the pistons. Without much else to do we buy k3-ve pistons and sacrifice the difference in height… :disappointed_relieved:

In those 15 days we only used the car “slowly” and we prepared for the first track day …

The result … it was “fun” but it was clear that there was a lot to do … much much much to do …

to be continued…


#2

Keen to follow your progress!

We would likely use the phrase “it was a mission” - when describing trying to track down hard to find parts.


#3

Tell us about the racing format. Sprints, mass starts…? This is great to see the Dai amid the Honda (and other thing). Chile - South America, very cool.


#4

Hi!!! it’s track-day format (delayed launch, you can’t overtake in curve), are 6-minute runs on track … after 4 or 5 rounds the cars are classified by lap time (until 1:08:00, until 1:05:00, until 1:03:00, etc), it does not matter the car or its modifications only the best time you did.

In the last race should be as close as possible to the target time but you can’t pass it, because you are disqualified, for example if you are in the 1:05:00 category and you make a time of 1:04:999 you are automatically disqualified (similar to the quarter-mile race)

It’s a funny format that avoids cheater that are slow all day to risk everything in the last round.


#5

Ok … continue …

As I told you before, it was funny … just that “funny”… the best time of the day was 1: 10: 478, second last place in the category.

The engine works well, stays a little over 7000 rpm but while the others are in 3° I go in 2° and while the others go in 4° I go in 3° … but (there is always one), the car doesn’t turn, the understeer was terrible … in fact, it’s something that I have been correcting but until today the car is not going smooth, it’s not going where I want to take it … you always go like fighting with the car.

For the second race I decided to try to make the car turn better …

Buy new shock absorbers, I ordered custom new springs (5 cm lower and 50% harder), we changed the bushings of the suspension and we installed a upper strut bar (also custom)

Manufacturing of the bushings (except the front swaybar that we buy Siberian Bushing)

IMG-20171228-WA0011

installing the strut bar

installing the springs and shock absorbers

well … after all that and with all hope we started the second race. The result, a little disaster, I will not say that the car didn’t improve, we improved the time to 1: 07: 199, a little more than 3 seconds, but the car continued understeer too much.

We played with the pressures of the tires (30 psi forward 40 psi back) to force the car to oversteer, it did not really work too much.

condition of the tires at the end of the second race

tomorrow third part …


#6

Ahh, how good is it having a lathe!. Nice work. Hey, I urge you to try putting the std front springs back in. You will get more grip to the front. 50% stiffer in the back may not be enough. Shorter rear shocks too will help. When you get the “sweet spot” it will be lifting rear wheels. A long shock will mean a tire staying on the ground and in corners only the outside wheel of a fwd is needed to be in contact with the groud. You have to make the front do more work, so more weight on the front wheels. A stiff rear will transfer more weight to the front. A soft front will help keep weight equal on both front tires. More neg front camber too. -2 to -4 deg, the greater if you can get it. Cut and shut the strut top mounts for an extra -0.25 to -0.5 neg (images here https://livetodai.com/t/not-quite-track-mr-gormsbys-l200/79/17). There are early Fords that have a near identical front control arm and there are some that are a bit longer and would give more neg camber and increased front track. (examples here http://www.burtonpower.com/parts-by-category/steering-suspension/track-control-arms-wishbones.html). Anyway, def try softer front springs, or make some chocks to go between the coils on the rear. I’ve done it with timber or rhs steel and zip tied them in for a quick test and tune. Essentially you are doing something like this.

image

The images show “wedges” used in NASCAR. During a race, if more grip is needed on any corner of the car they pull out a wedge. Softer corner of the car gives more grip than a stiffer corner.


#7

Mr. G I’ve been meaning to ask (and it might be more of a cover up solution), but, would going for semi slicks just at the front end help the back end rotate, or will it just make the car a nightmare to drive?


#8

It has to help. The rear does not do a real lot of work. If things are not set up right and the balance on the front wheel weighting is wrong then at least you have one semi slick fighting for grip instead of one road tire fighting on the front for grip.


#9

I had the same doubt and also thought that it could be more a covert solution :sweat_smile:


#10

Oki-doki… the next race is August 18 … this weekend I will change the front springs and tell you how it goes. :blush:

But it’s better to try to adjust the current suspension or definitely search for a solution of the Coil-over type? :roll_eyes:


#11

ok … let’s go for that third part…

As already commented, the car improved in this second race but it was not going well at all so with everything we did last month we started to think what else to do …

At that time the idea was making non-invasive modifications, in case i wanted to sell the car later, today I would say that it’s not sold :rofl::rofl::rofl:

One of the problems I felt was that the car was “very soft” as if the chassis was not rigid enough. I could not make the car oversteer …

solution … let’s fill the car with strut-bars and place a rear sway bar…or so we think…

Where the hell do we get strut-bars? we search search search search search the internet and nothing … suddenly we find the perodua myvi … it’s like the second generation sirion :thinking:, ultra racing has aftermarket pieces :thinking:… OK copy it …

And the sway bar? it looks the same as myvi… let’s bring it … we throw ourselves to the pool…:see_no_evil:

strut- bars of 4 points forward, 3 point lateral and 2 points back … the sway-bar finally was not 100% compatible (had to bend a bit the tips) but could be installed…

To finish we put camber bolts and set them to -3 °

The result? OK this is better … not perfect but better … the tail started to have oversteer but the traction was not the best … We improved the time to 1: 06: 499 and we finished 4th in the category … satisfied

The fourth race went without improvements and “surprise” 1: 05: 607 and we won our category :heart_eyes: :heart_eyes: :heart_eyes:, the Sirion began to become known and people talked about him. Other pilots approached me and asked me how I did it so that it would turn … well, It did not always turn…:sweat:

https://www.facebook.com/nvergaraa/posts/10212480527587423

the fifth race was strange … in the first round the rear strut broke but things were improving until in the last round I was disqualified for running faster than allowed in the category … 1:04:955 the best time I had done so far

In June there was a break and in July the race was very special so I’ll leave it for the next post.

That is more or less the story until here, after the next post I will focus on what is coming and how to continue improving this little Sirion

:hugs::hugs:


#12

If you go through my build thread you’ll see how I did a wet insert of a Koni into a std leg which also involved cutting its length down. This meant I could lower the car and still have bump travel. An external adjustable Koni Sport would be the way to go with yours. For the rear you should be able to find a Koni Sport from some other car make that would fit - note it should be a shorter unit than std when fully extended (no need to have a rear track the ground excessively).


#13

Something was lost there in the beginning of what I was writing. It went something like this…

In coil overs about the only thing readily available that is any good are BC Racing. Bilstein do a coilover for the Copen, but rare. All the fancy looking Malyasian units are rubbish and really do not work other than being “car park boasting bling”. On the rear you should be able to find a Koni/Bilstein from something else that will fit/work. There are other great brands out there. Price is an indicator of quality in this realm with the best being things like MCA (the Gold line), Ohlins, Penske, and so on.


#14

Amazing work on the bracing. This is becoming the Sirion I wanted to build when I had mine. Well done on the continuous improvements. Does the new 1:40.xx time mean you get to move up a class?


#15

yep … it means that I move up in category, i’m very very very happy for that. :grinning::grinning:


#16

Ok … I will continue with the story …

The sixth race is not exactly a race … we changed racetrack, the new racetrack is “Las Vizcachas Racetrack”.

A bit of history, really vizcachas is no longer a racetrack, it was officially closed in 2006 but it stopped being used at the end of the 90s.

The novel thing is that it’s a historic racetrack here in chile, it’s apogee was in the decade of the 70 and 80, I grew up watching these races on television, so you can imagine what it was like for many of us to run there.

Likewise, there were many older people who could not believe what they saw, it was like going back in time.

As it was no longer an official racetrack it could not be clocked, that’s why we all have the number 1. :sweat_smile:

The truth is that I do not have much to contribute to the car, just how happy I was to run on a circuit like this.

Here is a video on the Sirion

I also leave a video post event that summarizes what was.

now to prepare for August 18 where we will run again (change front springs Ready :smile:)

I almost forgot … these pilots increase the power of Sirion by 10 hp :rofl::rofl::rofl:

See you next time!!


#17

Wow great pics. Interesting track. Let us know how the springs go?


#18

I come with my status update …

Again I finish second last but of the next category. Time again we could reduce it, we finished with a 1:04:48x, half a second faster than the last time. The truth is I’m very happy with the participation and draw some conclusions. :hugs::hugs:

First, I didn’t like the new springs configuration… although apparently I was faster, the car was very difficult to drive.

What changed the most was his approach to the curve, when placing the softer springs the car was ultra oversteer at the entrance of the curve and when stepping on the accelerator lost traction (it was very evident the missing of LSD). :thinking:

Second, the bumping of the suspension was unpleasant … although thanks to that there are some very good photos of Sirion.

In spite of that, I must admit that the car better copied the half-speed curves and i feel that the exits were much softer.

My conclusion is that it too soft on the front making it difficult to enter the corners but improving the exit.

Another important point is that I have to change tires, today i have 185/55/​​r14 tires (Marshal Matrac FX MU11), obviously very soft in the corners.

Front tire (with -3 Camber)

Rear Tire (with 0 Camber)

The next date is September 15, however, we decided to make some changes to the engine, so I don’t know if it will be ready for that date.

The list of things to do is the following:

1.- Change pistons by Hi-Comp pistons (12.5 CR) :heart_eyes::heart_eyes::heart_eyes:

2.- Supercircuit Header 4-2-1

3.- If the time and money reach. We will place an aftermarket ECU.

One thing I need to discuss is the braking of Sirion, it’s not bad, but it’s not good either. Unfortunately, the Copen and the YRV did not arrive in Chile, so I do not have an easy 246mm brake option. How much must be done to put Applause brakes on the rear axle, keeping the front brakes?

A hug to all


#19

Looking at the front to rear pitch of car in the photo the spring balance looks good in that load transfer is right. The soft front should make turn in really good as opposed to worse. You could go another degree up to -4. A little toe out will help turn in also. On the issue of springs it may be that they need better damper control and slower compression rate (shocker absorber damps spring oscillation).

For Appluase rear I machined the drum/bell section off of some spare drums. The Appluase hat fits over that. The backing plate required boring out in the lathe and the four mounting holes to be redrilled (but this is on an L200). Because of the extra thickness of the drum/bell the caliper had to spaced out that exact thickness. On mine it made a noticeable difference in performance. There was no need to change the master cylinder as it was the correct bore and the stroke had enough capacity. I made some tubes up for the hand brake cable. Cable goes through the tube and the tube makes up for the extra length of wire poke out and these sat in the factory cable bracket.


#20

Thank you very much for your response… I really appreciate the help you give :grinning::grinning::grinning:

I really think that the problem may be in the dampers, if i change the oil inside the shock will it improve? getting to -4 of camber is going to be difficult, with the camber bolts the more i get is -3 :sweat_smile::sweat_smile:

with respect to the applause brakes I will start buying all the necessary parts … they are worth nothing in this minute