Adding Lightness

[Suffolk944]

While my quest for more power is at an end with what I have now, I still occasionally toy with lightening the car in the quest for more performance. I love the electric sports seats but I know they weigh a fair bit and so have thought about replacing them. Likewise removing the rear seats, removing the non functioning aircon, replacing the pop up headlamps with GTS style ones etc.

Guess my question is would I notice much difference on the road (as opposed to the track) if I went down that road or would I just be left with a less comfy car with worse headlamps than before which had gained no meaningful performance in either pace or handling ?

 

[Lowtimer]

I am sure others will know exactly how much weight that programme would lose, but let's say it is 100 kg (which I guess is about right). That is equivalent to around a 7% power increase, and will probably knock off about half a second on your 0-100 time. The less obvious benefits are the effective increasing of the spring and damper rates, and the reduction in roll and lurch and heave.

How significant would you feel the benefits to be? If you want to know, simply *add* 100 kg (or whatever the experienced lighteners here say it would be) to your car! Ballast it up with some evenly distributed sandbags, in the passenger footwell and behind the front seats, until the car is the relevant amount heavier. Drive it round like that for a good, long drive, a hundred miles over roads you know well, and get used to it. Then take it out again, and do the same route. Then all you have to do is imagine the same change again.

 

[Peter Empson]

Do it! [] I've always found it very noticeable on the road, the car simply does what you want far quicker. Naturally it will also improve your mpg (yeah right!) and reduce wear on consumables too.

 

[sawood12]

Nooooo! Why ruin the car? Why not get the air con fixed and just enjoy the car as it is? A very fast luxury sportscar. Do you notice a significant difference in performance between a full tank of fuel and an empty one? I couldn't and there's a 60kg weight differential there. Add a passenger and you can get a 140+kg differential - far more than you could hope to lose by ditching seats and lights) and even then I couldn't notice that much of a performance differential on the road, if any, and by the looks of my passengers reaction they certainly didn't think the car was sluggish in anyway shape or form.

It is easy to get used to the level of performance at any given point and forget that you've already got a light car by modern car standards (lighter than a GT3) with more power than a lot of modern cars. Whichever way you cut it you've got a very fast car there, why ruin it unless you want something more track focussed?

 

[Peter Empson]

Why on earth would it be ruined?
Nothing discussed would not be reversible (ok the headlights and air cone would be a little time consuming to refit, but they wouldn't be my first choice anyway). Put some proper bucket seats in (which I find are far more comfortable anyway), remove the spare tyre and rear seat upper section and there's a lot of weight saved very easily. As for you not noticing the difference, well I'm a little surprised, but Jon ought to give it a go for himself (I'd be rather surprised if he didn't).

 

[944 man]

You only benefit from increased horsepower whilst youre accelerating; but you benefit from decreased weight whilst accelerating, braking and turning (and dont underestimate how much difference 100 kilos will make to braking and turning either)!


Simon

 

[Tam Lin]

I found that high up components made the most difference: I replaced the sunroof & gubbins with a carbon panel, and that definitely changed the handling in corners on the road. (The initial slight understeer then flop-lean of the car went)

One thing to bear in mind is to take weight off either in the middle, or at both ends..most of my initial weight savings were at the rear, which did nothing for the balance. Once the battery was moved to the rear (I have an 924S) and the 944T gearbox with cooler & LSD was fitted, the car was balanced again, which was nice.

 

[zcacogp]

Funnily enough, I was pondering exactly the same thing after a thread on here about lightness the other day. It all makes good sense, but I can very much identify with Scott's comment thus:

ORIGINAL: sawood12

Nooooo! Why ruin the car? Why not get the air con fixed and just enjoy the car as it is? A very fast luxury sportscar. Do you notice a significant difference in performance between a full tank of fuel and an empty one? I couldn't and there's a 60kg weight differential there. Add a passenger and you can get a 140+kg differential - far more than you could hope to lose by ditching seats and lights) and even then I couldn't notice that much of a performance differential on the road, if any ...

I struggle to tell the difference between a full fuel tank and an empty one, and between having a passenger in the car and no passenger. (Although the most common passenger is Mrs zcacogp, and she is pretty miniscule!) Having said that, I do notice the difference between having a full boot and an empty one, so perhaps it's balance that I am more sensitive to. Either way, I quite like the leather sports seats and the pop-up headlights, and the rear seat is also used occasionally, so would need to be convinced of some significant gain to be had before I ditched them.


Oli.

 

[Suffolk944]

ORIGINAL: zcacogp

Funnily enough, I was pondering exactly the same thing after a thread on here about lightness the other day. It all makes good sense, but I can very much identify with Scott's comment thus:

ORIGINAL: sawood12

Nooooo! Why ruin the car? Why not get the air con fixed and just enjoy the car as it is? A very fast luxury sportscar. Do you notice a significant difference in performance between a full tank of fuel and an empty one? I couldn't and there's a 60kg weight differential there. Add a passenger and you can get a 140+kg differential - far more than you could hope to lose by ditching seats and lights) and even then I couldn't notice that much of a performance differential on the road, if any ...

I struggle to tell the difference between a full fuel tank and an empty one, and between having a passenger in the car and no passenger. (Although the most common passenger is Mrs zcacogp, and she is pretty miniscule!) Having said that, I do notice the difference between having a full boot and an empty one, so perhaps it's balance that I am more sensitive to. Either way, I quite like the leather sports seats and the pop-up headlights, and the rear seat is also used occasionally, so would need to be convinced of some significant gain to be had before I ditched them.


Oli.

Am exactly the same Oli, I can see that lightening would help (to some extent or other) but I do like all the gubbins that the car has attached to it at present, hence I suppose my canvassing of opinions here from the 944 massive...Plus of course there is the additional expense of new seats etc etc when really I have spent more than enough on tweaks already.

 

[zcacogp]

ORIGINAL: Suffolk944
Am exactly the same Oli, I can see that lightening would help (to some extent or other) but I do like all the gubbins that the car has attached to it at present, hence I suppose my canvassing of opinions here from the 944 massive...Plus of course there is the additional expense of new seats etc etc when really I have spent more than enough on tweaks already.

In fairness, you could sell your current seats to cover the cost of the replacement buckets (I don't think that bucket seats are that expensive); my leather sports seats came from BennyBoy on here, who was putting lightweight buckets into his car.

Having said that, if you keep the original seats then you can return the car to original spec when you sell it, which can be useful.

(But the argument differs when it comes to your non-operational air con. That really is dead weight ... the logic of fixing it or removing it is irrefutable! [] How much would you save by binning the system?)


Oli.

 

[Suffolk944]

Yes, could sell the seats to fund matters but suspect I would rather keep them to be able to revert to comfort mode if felt the need. Quite right about the bucket seats not being that excessively pricey, as for the aircon am not sure about the weight but I suspect someone will be along presently who could tell us !

In truth my next expenditure (if being sensible) needs to be sorting out the bottom of the wings plus a front end respray. I have a vented nose panel from D9 which I intend to fit at that point which perhaps can be the start of the lightening process !

 

[Neil Haughey]

I have done just under 1K miles on the road in my race car now and in all honesty the only thing I miss is the quiet of a stock car. I have driven it back to back with our 968 which is a tad unfair as that thing is uber smooth and refined to drive being a tiptronic but I think I am safe in saying that next to a stock S2 its only the noise that bothers me. Even then however it actually isn't really any noisier than the mini I used to drive about it and yet amazingly rides much better.

I guess this question really does come down to what sort of person one is. If your like me or Peter the benefits far outweigh the negatives but Scott is correct in that the uniquely decently refined ambience of the 944 is shattered. My personal opinion but I just don't see the point in any 944 any more as a nice road car but they undoubtledly do make great track cars. If you do like those reasonably refined aspects of the car then yes pulling out all the sound deadening and all that will "ruin" it.

 

[zcacogp]

Good observation Neil. And throw in the purpose of the car; I will always have a different point of view to the majority on here as I use my S2 as a daily driver and only car.

If I drove it less on the roads, and then only for fun, I would probably be more inclined to think about something more radical. And weight saving would need to be the first port of call. As it is, given I am looking at doing the thick end of 1000 miles in the old gal in the coming 2 weeks, with wife and a bootload of catering equipment, something that is refined and (moderately) quiet is going to be more popular that something that is more fun, quicker but noisier.

(Although, given that a reasonable chunk of those 1000 miles are going to be on Welsh mountain roads, a lighter and more nimble car is certainly appealing. As would be the option of turning off the Passenger Seat Speed Limiting Device ... [])


Oli.

 

[Peter Empson]

ORIGINAL: zcacogp
I struggle to tell the difference between a full fuel tank and an empty one

I have to admit I don't find much difference with the fuel load, I guess it's so low down that its impact is minimal. A passenger does make a difference, but when you've got someone along side you you might not be pushing as hard to find out (or maybe that's just me). I know that with the slight oversteer imbalance I had yesterday I found it easier to control without a passenger (that's my excuse for a few scrappy pax laps anyway []).

I defy anyone not to remove the spare tire, tools, rear seat back and rear carpet and not notice an improvement in the dynamics - just 15 minutes work to give it a go (and remove the passenger seat to get an idea of what having a pair of lighter seats would be like).

 

[TTM]

I liked the handling without the rear seats until I decided I needed them to settle the rear end better, as it was beginning to lift off and behave on its own under heavy braking, and I also wanted to be able again to hide luggage with the roller blind.
The latter shouldn't be an issue on car with split rear seats, thanks to the separate elastic luggage cover, though.

Unless there is something really wrong with A/C (needing a new compressor or leaking A/C lines) I would rather have it fixed than remove it.
I removed it on the turbo as it required too much work to be made operational again and it just felt at odds with how the car was being turned into - significant engine mods, buckets seats, etc.
Even though I do not like A/C in general (well, my throat doesn't), I do not plan to take it off the S2 as it's still running fine and I think it is coherent with the rest of the car which features comfort, heated seats, the removable sunroof panel and is not meant to be as fast as to ever require removing any comfort features.

Depending how you are physically it may be a gain or a loss to move from Sport seats to bucket seats.
Regardless, the original Recaros that came with the 968CS are very expensive when they come by, which is not often, but such or similar pieces would look very nice and appropriate in a black 944(T), I think, if covered with nice black leather with the backs painted in black.
Depending on spec, original leather seats can be as heavy as a dead horse - I remember taking some out of a fully optioned 968 Lux and we weighed them at about 25kg each...!

You may want to try looking for a lighter bonnet. They are usually not cheap, especially those with a decent finish, but I have always heard good things about fitting a lighter bonnet. This is one part I wish to fit in the future, and one with louvres to extract some of the ridiculous heat the engine generates.

Edited to add : I think the original pop up headlight assembly, with motor and all, represents 15kg, and the A/C system is about 20kg, most of it contributed by the compressor.

 

[Diver944]

When I used to track regularly I removed the following items before each trackday then replaced them afterwards - spare wheel, tools, compressor,boot carpet, rear seat back, electric leather front seats (replaced with 7kg bucket seat), floor mats. That little lot comes in at just under 100kg and it was easily noticeable when braking and cornering (or it might just sound faster with the lack of boot carpet [] ).

If you then get really anal and bring your own fuel in 25L jerrycans and never have the tank more than a 3rd full it is even more noticeable []

 

[Suffolk944]

The aircon condensor has a hole in it - when I got the car three odd years back I think the price for a new one was around £800, plus fitting of course. Add to that the fact that the systems been non-op for a number of years and may need all sorts of other things replacing/fettling I dread to think how much it may come to in order to resurrect it. [&:]

 

[Suffolk944]

Of course I could have spent the money I have splurged on gaining more power/replacing the suspension etc on the aircon and wings/paint instead but where's the fun in that ! []

 

[Neil Haughey]

I imagine its a fair amount of work to remove all the A/C components but if it doesn't work and your not going to spend on fixing it then its just dead weight being lugged around for no gain.

On the flipside I really really like having fully working A/C in our 968, we haven't needed it much in recent years but on the odd days when it does get really hot I find it makes a massive difference.

The race car is a different kettle of fish altogether, its so full of holes that even with the blower off you get a lot of air through the cabin. For this reason I find it OK as long as the ambient temperature is in the low 20's. It does heat soak on track but I guess every front engined car is going to suffer that to some degree if tracked.

 

[944Turbo]

I got a new condensor from cool it and I am sure it was around 160 and with all the gassing / seals / drier on top came to about 250. I fitted the condensor which probably saved a few pounds of labour and there may have been some vat on top but no where near 800!