CLR Project Leichtbau: adding lightness to the tune of 250kg

ragpicker said:

ELA, have you encountered any issues at speed with all the weight removed? Any 'waftiness' or floating?

If so are there any aero consequences to consider?

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Hi Ragpicker, I did some testing early on but haven't driven the car since about last October. Since then a massive amount of work has been done to the car and around another 130kg or so removed. Also complete suspension change as currently fitted (Ohlins and top mounts) and I am in the process of changing every single remaining part of suspension; some 186 individual parts will replace the OEM set-up on top of what has already been done

Carbon panels are now all prepped and at the paint shop. Wheels are causing me a massive headache, but I'll talk about that another time.
Brakes are the only part that is currently holding me up but that is neither here nor there as they can simply be fitted once done.

So in answer to your question, in around 2 weeks I hope to have the car somewhere close to finished. I will then start trialing a few geo settings and suspension settings. Once a good base has been established, I'll do some high speed runs 170MPH+ and see how it all combines. To be honest though, if anything, I expect to car to be much more stable than before as I have reduced drag and lift. There will be more ground effect, lower CofG, better weight distribution, I have added a little rake angle, will have much stickier tyres and the suspension will be completely rose-jointed. It should be very stable and planted. The only unknown really is how the ducktail will alter things. But the fact they use them on the 997SC tends to give me no real cause for concern.

Truth is in the pudding though, so I'll just have to see how it all pans out :thumb:

Slight diversion today: I bought ELA's wheels and thought you might like to see how the look/feel.

Bear in mind my car already runs GT3 height and "fast-road" geometry. She used to look like this (I shall be keeping the wheels/tyres, explained later):



The OEM Carreras are extremely light already, but the new Fuchs save 1 KG on the front and 4 Kg on the rears, which is always a good thing.

Here's some pictures with the new lightweight TSRs on:









Michelin PS4s for the fronts (went for 225/45 R17 for maximum front-end grip)

Michelin PS2 255/40 R17 PS2s on the rear. A LOT more sidewall both ends!

Looks-wise, they are really nice; I'm surprised how much I like them already and it seems the 996 suits itself to a retro look, strangely (I always considered them the most futuristic-looking). I guess ELA (and RPM Technik) are onto something?

As you can see, the wheels really fill out the arches! They are so nearly too bulky-looking, but I do genuinely love how they look (and maybe I need a ducktail, too.....).

I was really pleasantly surprised how they drive, too : it definitely feels more "rubbery" with the bigger sidewalls;it feels more "old school" as well, with a touch more nose bob and a lot less fidget/crash than modern cars tend to have.

For track work I think the 18" OEM wheels (and 30-section tyres) would be better (there is a touch of sideways motion), but for the road these are significantly more comfortable - and I didn't think it was bad before! The Exe-tcs run a soft, progressive-rate spring and low rebound, so they are really comfortable. With these tyres, the car is really, really comfortable. I would expect an even more marked improvement on firm set-ups.

Widening the track (thanks to low offset on the wheels) and down-sizing the rears from 285mm while keep the fronts at 225mm cross-section gives the car a little more bite at the front end, too, it seems.

Considering the small weight-loss, the change in character of the car is quite large, but it's definitely for the better. Looks are subjective, but I really like it and hope you do, too.

:worship:

Now all you need is a ducktail......? :cloud9:

Though just as they are that is a great look :thumbs:

Glad to see an update on here. I was just thinking yesterday that all was a bit quiet on the CLR front, knowing that Rich would be beavering away in the garage getting ready for his Dinslaken deadline.

EGTE - Great purchase! I toyed with the idea of them and changed my mind daily. In the end I decided to stick to my original plan of Aerokit and GT3 wheels, etc.
I was going to sell my Aerokit to recoup the costs if I bought the wheels as I would follow Rich's concept of standard bumpers, no skirts and maybe a duck tail as I think the bulkiness of the Aerokit may dwarf the wheels a bit, plus I like the retro simple lines when coupled with those wheels.
That was just my plan though and the wheels look great either way.
I decided I didn't want to be doing a bad mash up of Rich's car, which is what mine would have been if I went for the minimal look, so I didn't waste his time about the wheels. I'm glad someone on here bought them.

The widths are perfect and the finish is really authentic with a nod to the early cars.
Some quality components on your car then! Along with the Exe-tc's. Very high end stuff. Lovely car. Nice one! :thumb:

I think the suit a black car better than the silver. For me they were just a touch too much with the silver. On yours though they look luuuuurvleeey!

:thumb:

Stunning Russ, they sit just perfect on your wonderful car

Marky, I've been a little quite the last week but as correctly guessed I've been beavering away in the hintergrund

I can't begin to describe what a nightmare the wheels have been to resolve. Firstly the original set were a real test and I'm sure EGTE will testify; there is literally a gnats ***** clearance in some areas :grin:

So I had sorted the new rears out. But getting fronts was proving impossible. I managed to get some through the back door, but when I opened the box they were the 'Natural' finish (silver). I couldn't believe it. I took the day off work and drove over 400km to 3 different wheel paint specialists who all said they couldn't do anything with them as they are so tricky to do and only Fuchs can fix it.
I have been in constant talks with Fuchs for about a year now and lets just say, that if you want RSR finish, there have been some waiting since last April and there are no signs of this improving in the next 5 months...
I was proper stuck. I had sold my custom wheels, sold my OEM wheels and had invested in 2 rear Fuchs RSR's and couldn't get the fronts to match. I was literally about to throw the towel in. Bear in mind I have a million and one other issues going on simultaneously so this problem is something I never expected. It is now semi resolved though, I have had to go for a slight compromise which means a pretty serious suspension re-design but it is all just about sorted now. Remaining suspension parts are in production, wheels are arriving today hopefully (nice B-day present, not that I can fit them) so hopefully next week I can make serious inroads into getting off the jacks. Another bit of bad news last night. I phoned up about collecting the doors, ducktail, bonnet and front wings from the paintshop (originally planned for this Friday), to be told they wont be ready until next Friday now. I really can't afford to lose another week but what can I do :nooo:

To top this off, I inadvertently found a bit of corrosion the other day that needed some attention. Things like this all add up and can be a bit testing sometimes!

Still almost there now, I have some RUF mirrors being made from Carbon looking like a goer very soon, lightweight brakes maybe another 3 weeks away so pretty much all bases covered now from what I can do.

Just a remap, then TUV, geo, set-up and testing phases to do after this lot. It's very tight but fingers crossed all potential show-stopping issues now resolved

Sounds like an absolute nightmare week. Very demoralising, but when you're so far through it like you are I imagine you've got to just suck it up and keep going?

Are any of these challenges you are encountering going to be any easier if/when you do this again?

Still loving the updates dude, nice to hear the rough with the smooth. It gives an appreciation of the effort and time which you're putting into it.

:thumb:

ragpicker said:

Sounds like an absolute nightmare week. Very demoralising, but when you're so far through it like you are I imagine you've got to just suck it up and keep going?

Are any of these challenges you are encountering going to be any easier if/when you do this again?

Still loving the updates dude, nice to hear the rough with the smooth. It gives an appreciation of the effort and time which you're putting into it.

:thumb:

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Producing this car has certainly had it's up's and down's but there are still potential areas of the design that a prolonged testing phase may highlight as needing to go back to the drawing board for; although at this stage I'm reasonably happy that the 'completely redesigned parts' will surpass the originals in terms of reliability and strength.

In terms of going forward and replicating; I now have manufacturers, suppliers and machine shops that I can work with and upscale. Doing everything for the first time is what is difficult, repeating or having bits ready on the shelf, should be relatively simple by comparison. I have all my drawings done and samples of each part, so there wont be anything like the trouble I've had to go through the first time. I would also hope to have all of the following CLR customised parts on the shelf to save me any supply hold-up for 996 and 997:

-CLR steering system kit (all hardwear)
-CLR Ancillary drive belts
-CLR Ohlins mounting kit including pillowball top mounts (front Adj camber)
-CLR lightweight 2-piece brakes
-CLR Front adjustable pillowball LCA
-CLR Front adjustable pillowball castor arms
-CLR Front adjustable pillowball drop links
-CLR Rear adjustable pillowball LCA
-CLR Rear adjustable pillowball castor arms
-CLR Rear adjustable pillowball upper control arms
-CLR Rear adjustable pillowball toe arms
-CLR Inconel/carbon exhaust
-CLR LWFW and clutch kit
-CLR Gearbox mount
-CLR Throttle (exchange only)
-CLR Re-map (Out source upto 8 week notice depending on race season)
-CLR Carbon ducktail (with or without brake light)
-CLR Carbon RUF mirrors
-CLR Carbon Doors
-CLR Carbon Door cards
-CLR Carbon front wings
-CLR Carbon bonnet
-CLR Carbon Roof
-CLR Forged wheels
-CLR Carbon seats
-CLR Lightweight low-mount seat rails

Also other parts I use for a conversion:

-CUP steering wheel
-Lightweight battery
-Titanium wheel nuts
-RSS Engine mounts
-997 SSK
-Underdrive pulley
-Lexan windows
-Powerflex ARB bushes
-LTT 71.c
-O2 sensors (If required)
-MAF sensors (If required)
-ICV (if required)
-Water pump
-Various resistors for airbags...
-Clutch release bearing
-Alcantara material
-wiper delete kit
-OEM Porsche dash blanking switches

There is also a lot of custom work done to existing components like the Radiator cooling, brake cooling, power supply loom, interior full re-trim and weight reduction, re-spray, resto-corrosion treatment...

That little lot is off the top of my head so probably a few bits I've forgotten; but you get the idea, having parts ready will help enormously to ensure a smooth turnaround.

Going back to the origin or the question, had these turn up yesterday:


And whilst having the CUP2's fitted I went to the paint shop and managed to talk them into getting all my carbon bits painted earlier so that gives me a few more vital days

Here they were all primed up


I also gave the front bumper black plastics a bit of a paint touch-up the other day and also trial fitted the CF doors, corrosion treatment and prevention, suspension arm mountings prepped, so still bits going on but it would be a whole lot better if all the remaining parts were actually in my hands

:?

:superstition:

:thumbs:

Looking like it's going to be fantastic Richard.

When you fitted the RSS engine mounts did you get vibration through the car at low speed/revs or when Erving the engine while stationary?

Had some fitted this week and only had a very short drive but noticed quite a lot of vibration that has never been there before. Are there different torque setting when fitting the mounts to get around this or will they improve after some miles?

budflicker said:

Looking like it's going to be fantastic Richard.

When you fitted the RSS engine mounts did you get vibration through the car at low speed/revs or when Erving the engine while stationary?

Had some fitted this week and only had a very short drive but noticed quite a lot of vibration that has never been there before. Are there different torque setting when fitting the mounts to get around this or will they improve after some miles?

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Can't say I noticed anything as pronounced as you describe Peter and being a relatively simple mod to fit, I really can't imagine whoever fitted them could have done much wrong. Might be worth going back to them and describing the issue you have

New997buyer said:

:?

:superstition:

:thumbs:

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A bit cryptic for my simple brain Paul, care to enlighten

I think he just means that the 996 CLR is almost upon us. We are all waiting with baited breath to see the finished article.

Also, I would be really interested in what advice you would give on how to lose the most weight for the least cash. As in, given a budget of £1000, what would you remove, and what bits would you buy/replace in order to improve the car the most?

I'm guessing seats and a knockoff cup style steering wheel, and then remove all the bits that you've detailed in this thread. Correct? Or are there some items that have really made more of a difference than expected?

It is actually very difficult to answer this question directly. Reason being some things, which I can highly recommend, can only be done at certain points; for instance, take the PAS conversion: 'a key factor in this project', but I couldn't recommend it if you are only losing 50kg or so. The PAS conversion in combo with the A/C system will reduce mass by 21.2kg, and pretty much all of this weight from the rear of the car improving weight distribution as well as the weight itself. It also has the major benefit of the engine parasitic drag reduction, reduced heat-soak, aid engine cooling, lowers CofG, improves access to engine for servicing etc. But if the car is still weighing 1300kg I would never recommend it.
Also it would depend on how this budget is spent. I would recommend the LWFW as the first mod; before seats and steering wheel even. But if you factor in labour then in it not possible. You also need a special clutch to optimise this modification. So again you may be able to get a LWFW within budget, but add on all the extras and there is no chance.

So I would look at stripping as far as you feel comfortable, this might net you 50KG, but be prepared to lose certain services, HIFI for instance. In terms of the best value for money mods I would probably go in this order (bear in mind these are no driven by weight loss but best value and improvement in the car overall):

-200 Cell cats
-BMC Panel filter
-CAI
-997SSK
-Underdrive pulley
-RSS Engine mounts
-71.C LTT
-Complete suspension check for worn components

None of the above has anything really to do with weight, but I feel this is where your money would be best spent first to improve your car before embarking upon a weight-loss program.
Hope that helps.

Thanks for the reply. I have a GT3 body kit on mine, and I believe this creates a high static pressure area where the air inlet is already, so that should be cold air induction already taken care of. That said, it's something I could test with a manometer to really find out.

I've also already got a LWFW. I'm not a big fan from a driveability standpoint, but it's something I'm preprared to put up with for the weight reduction.

I've been having gearbox and linkage issues and recently bought a 997 gearbox to put in, and I'll be paring that with the 997 SSK as much because it's needed for compatibility reasons. This is however dependent on the 997 gearbox accepting my G96 gearbox's LSD.

I shall certainly be putting in a low temp thermostat.

If I can find or make an underdrive pulley then I probably will. £200+ for a new one seems a bit much to me.

Suspension wise, I have an M030 setup on there from new, and it's definitely tired. When I can afford to I'll put something better on such as rebuilt PSS9s. I'd love to have new Ohlins but I can't justify that king of money. Most of the coffin arms and other bits have been replaced over the last two years, but I would really like some adjustable rear toe arms as getting and keeping my preferred alignment(no camber and no toe) is a ballache. As soon as the camber and toe settings are lost the car becomes more understeery and harder to drift.

I've been considering having an exhaust made that would get rid of the existing mufflers and have 200 cell cats feeding to a small centre box with a centre exit. It would be loud but much lighter. I strongly feel that loosing 25KG or more from behind the rear axle will have major benefits. Also I have PSE exhaust currently, so selling that could potentially cover most of the cost.

I'm also trying to track down some cheap Sport Design wheels in order to use the rims from the front with the centres from the back to lose a few KG from the rear wheels. That way I can go down to an 8" rim with a 245 section tyre and kill some understeer and lose some unsprung weight.