Zubans LY RS200

[Zuban]

Yeah no probs I’ll do a post tonight when I can get to my pc and notes. I made a choice not to cut into the body or go fibreglass etc, partly on cost and mostly on making sure I had covered all other options before resorting to that.

The engine is stock internally but with a lighter flywheel, lighter exhaust pulley, crank pulley and the aux belt has no idler pulley and the alternator is under driven as I’ve used a clio mk2 crank pulley. So somewhere close to 5kg off the rotating mass. Also on the day of the dyno the wheels fitted were 16’s with 205/45/16 tyres at 15kg a corner vs the stock 17 inch speedlines at about 19.5kg a corner so roughly 18kg of wheel weight less in total and a 5-6% shorter gearing aswell. So you can see where some weight has been saved too.

The dyno I used is known to be quite accurate but it’s also an inertia dyno so as I understand it the reduction in rotating weight plus gearing is picked up by this type of dyno resulting in the higher wheel power figure. On a brake type dyno I’m not sure the result would be the same, would likely show its just a very healthy stock engine. The thing that matters though is the weight reduction of the rotating parts on the engine, plus the less weight to rotate in the wheels etc does translate into faster acceleration so the dyno is reflecting that. At least that’s my undereducated understanding of it.

 

[Zuban]

With 1121 as the starting point when it was last weighed with around 17-20kg of fuel (was showing half a tank. My notes aren't great but the main things I've done to reduce weight are:

1. Dashboard stripped to a single skin and remove plastics around the steering column, around 6.5kg
2. Rear wiper removed 1.13kg
3. Heater matrix removed 5.6kg new heater weighs 1.23kg saving 4.37
4. Tool kit in boot floor taken out 2.1kg
5. Radiator fan removed 2.95kg replaced with lightweight 1.35kg saving 1.6kg
5. Remove rear bumper internal plastic 3kg
6. Front undertray removed 1.26kg
7. Front door cards swapped for ultra light card 5kg
8. Rad support bracket replaced with aluminium box 2kg lighter than original with legs cut off.
9. Modified the front bumper removing much of the internal plastics, notes aren't clear here but in the end its down from i think 14-15kg stock down to just over 6kg.
10. Glovebox gone it weighed about 2kg.
11. The steel bar that sits under the dash bar got a bit more work, removed most brackets and cut down excess metal. Dont have notes on that.
12. Head unit removed 1.4kg
13. removed 600 gram bottle of window cleaner I forgot was in a side pocket.
14. cup spoiler removed 3.35kg
15. Diffuser and brackets 7kg.
16. Two seat mounts removed which were 13kg between the two, and replaced with a single pair of custom side mounts at 1.5kg saving 11.5kg
17. Removed the previous two seats which were 17kg between them, and replaced with a single 6.5kg seat.

I'm forgetting there is more i had planned to do that i haven't got to yet, so its probably closer to 1050kg with the same fuel load in it, in reality as i have added a couple kilo with the splitter and bits for the computer, I've got a short session on track this weekend so had to put the car back together as it was, once I'm past this weekend will look at getting on with those next which should take it under 1040kg all being well.

 

[Zuban]

few more pics of changes, the front bumper weighs a lot stock, which is weight hanging out Infront of the front tyres, so all the plastics in the large mouth area are gone, and i've trimmed the bumper a bit, replaced with some mesh, and some abs sheet to reduce the size of the opening, quite simply tied together with tie wraps that you dont notice until closer to the car. I'll be playing around with ducting for the rad etc to minimise the amount of air going into the engine bay in the future. The black plastic part with the numberplate on it is also trimmed and bonded to the bumper.

The plastics above the crash bar are all gone as well, the bumpers outer shell is strong enough, the dark plastic part that is held to the plastic slam panel has been trimmed to minimum and bonded back to the bumper shell with adhesive. It does leave the bumper feeling a bit flimsy, i had it sitting off the car and a strong gust of wind flipped it over. I always intended to run a splitter so the tie rods from that are attached to a lightened crash bar, so the bumper ends up over all being well supported and not had any issues with it yet.


There is still work to do to the interior, but its enough for a quick track excursion. Its not pretty but its a work in progress.

 

[Zuban]

Great chance today to contribute to good causes and get a shakedown of the latest changes at Golspie track n show at the sprint circuit there. Met up with another few Renaultsport owners which was cool one of which kindly sent me this picture.


It was a really well run event with hour long slots allocated for up to 8 drivers to take a sprint style go at the track, its a small track, but very intense and physical due to the nature of the corners. Unlike last year, the rubber seemed to have been washed away by the recent rain etc, so it was a very different track to the last time I drove it.

Gone was the huge amount of grip, and it was a very slippery track as you can see in session 1.

Tyres are a set of NS-20's as was expecting wet weather or damp.

I ran in the second batch of cars, and the track was just drying out so it had some surprises. As it was a show day for charity, no timing, and a decent audience pushing myself and the car as hard as possible was not on the agenda, especially since I had only put it back together a few days prior.

Great fun though, and the car felt great, performed flawlessly, and nothing fell off. There was a lot of interest in the car and some really good comments following the display.

 

[Zuban]

Was doing a little fettling today so took some pics of things I didnt when rushing to get it back together.

Inside of the front bumper, haven't had any issues so far with this and it feels really light compared to standard,


The radiator support has been replaced with a bit of box section aluminium, weighs about 800 grams and cost £15. Funny story with this is years ago when the original radiator was holed, when i replaced it i wasnt paying attention and i used the wrong holes for the rubber supports on the bottom. This gently twisted the radiator so that when i took it apart end of last year, i realised i could now just straightline the bottom mounts due to the twist in the radiator, so was pretty simple.


Noticed some rubbing with the 225 wide tyres on the 8J ET25 rims.


So set to trimming things to make sure they clear. Also gave a bit more clearance using the 12mm spacer trick to move the top of the arch out a little


And whilst I was at it I trimmed it enough to clear some 245/45/R16 tyres on 8J ET25 rims.

 

[Big Ben]

What’s the thinking behind going to a 16” wheel? Is it cosmetic or are you looking for performance gains?
Sorry if I’ve missed it!

 

[Zuban]

mix of reasons really, its generally cheaper to get a lightweight wheel in a 16 for example I have a set of JR3's in 16 x7, they weigh 6.6kg each but cost me only £130 a corner, getting a 17 inch wheel that weighs similar is generally over twice the price.

I can run a 205/45/R16, so the tyre is also lighter, and given the car is so light compared to stock, is adequate for good performance. Its also a common size for semi slicks. the combined wheel tyre combo of the 16 x 7 + 205/45/R16 is 15kg a corner, that's vs a smidge under 20kg for the option speedlines I had originally plus a 215/45/r17 tyre. But achieved at a much lower cost than sticking with a 17 inch rim.

In addition to that the 205/45/r16 is also 5.8% smaller, so it acts as a shorter final drive enhancing acceleration without altering the gearbox. That's probably the largest part of why it registered 191 wheel horse power, 217 at the flywheel on an inertia dyno, along with the weight reduction.

I also have some 16x8 rims, a bit heavier than the 16x7 at 7.7kg but again not crazy money at £160 a wheel. I'm experimenting with a staggered setup of wider front options relative to the rear. and some different tyre diameters, again altering the final drive, and hopefully find the right balance between them. Its a bit more cost effective to do this on a 16 inch wheel and tyre, I have three sets of wheels overall for a few hundred more than one set of oz superleggera's for example.

The 16x8 with a 245/45/r16 i'm testing at the moment is the same diameter as the stock 215/45/r17 but its a bit wider, and still lighter than the stock wheel/tyre.

So really it allows me to play around with different options for better acceleration or better grip without breaking the already very broken bank!

 

[Zuban]

Short update to my build thread, its been a while since I've done anything with the Clio, after the last round of light weighting, I have a steering fault that means it needs to be recalibrated, I can either buy a clip tool, or wait for the RStuner update that will let me do this, and as I don't need the car I decided to save the tax. So this meant when time came to have another run to the sprint circuit at Golspie the best option was to trailer it which is the first time I've done that.

An early start allowed me to witness the eye of Sauron.



A quick stop whilst I checked the straps, which was a good idea as one of them had slipped.


As I had gone up myself rather than part of a club, I randomly ended up parking between two mk2 Clio's and even better we all shared the first track session.


This is the bit where I should post some video's, but the camera ran out of battery during my dry sessions, and I have some very messy wet footage due to battery's that despite charging the night before, decided to go flat at annoying moments. The good thing is it seems I was on average 2 seconds a lap faster than my previous run in April, that is despite the mixed weather with fairly consistent light rain.

I am putting this down mostly to going back to a square tyre setup rather than wider fronts which whilst they rotate quicker, made me feel like the car was losing rear grip. The square setup returned a lot of confidence and allowed me to focus on playing with how to corner, what gear to be in etc.


A safe return home.


A couple things worth mentioning, I swapped to a lighter radiator fan, since installing it, the thin bolts that pass through the rad wore a hole in the radiator, rather than buy a new rad I used some steel stik to close the hole, and re-enforce the other fan mounting points, this repair held fine all day for around three hours of running on and off track.

I had previously swapped the in cabin heater system with a T7 design small windscreen demister, I remember someone else had the issue that it and its fan are not really enough to clear the windscreen, I found this too, and added a cheap high speed 12v fan from amazon and added it to the setup for a tiny amount more weight, and now have no problem demisting the screen. Happy to share more detail.

Lastly I recently removed the cup racer aluminium x brace from the front, nor the stock subframe to body brace, after some debating, I decided to run without it, and changed to a some high tensile hex bolts. Weight saved was near 3kg, which importantly returned some ride height ( important when running 16 inch rims), and under track use, I had no problems at all. Keep in mind I am using a cup racer subframe which does not have the same scope to move like the oem one.

 

[Zuban]

Some photos nicked from facebook.

 

[Zuban]

probably the best vid from the day, weather and track were changeable but really good day overall