Peter Empson
PCGB Member
Exactly, this is why racers will spend a lot of money lightening their car beyond the regulations and then use ballast to meet the minimum weight as they can position it wherever they want it (within reason).
Quest for lightness.
- Thread starter ocallen
- Start date
Exactly, this is why racers will spend a lot of money lightening their car beyond the regulations and then use ballast to meet the minimum weight as they can position it wherever they want it (within reason).
Tam Lin
New member
Not sure about this. At Beford Autodrome I let an Elise overtake me (924S with original engine on very long straight meant that the top speeds were very similar), as he was quicker/better driver. We both turned in, me following in line, and by the time I noticed he'd lost it and took evasive action, he had already spun about 540 degrees & was facing me. I would not have fancied catching that spin from inside the Elise...
Peter Empson
PCGB Member
The 944 can get to some ridiculous angles (and back from) that many other car layouts could not dream about. The mass of the car means you have to be quite precise to correct it but the degree of slip can be much greater and there's often quite a bit of time to get it back under control.
Talking of the Elise, it's best to remember that this isn't really a mid engined car as such, it's closer to being a rear engined design. However my experience of mid engined road cars is that whilst the limits may be higher they will give you much less time to react when it all goes wrong. They do tend to spin in a straight line quite neatly though [
].
Talking of the Elise, it's best to remember that this isn't really a mid engined car as such, it's closer to being a rear engined design. However my experience of mid engined road cars is that whilst the limits may be higher they will give you much less time to react when it all goes wrong. They do tend to spin in a straight line quite neatly though [
].
944 man
Active member
ORIGINAL: Peter Empson
Most of the weight has gone from the rear of my car too, although I can't say it's ever caused me any concern, but I guess my suspension was quite tired when I started out (it didn't look too high even with the lightweight hatch). Nowadays I like to have my suspension fairly regularly setup/corner weighted and the balance is very good.
Naturally I agree about the bonnet and hatch, but they're both fairly big and expensive things to do and will be more of a compromise than a lot of people will want at first (admittedly this is less of an issue with the bonnet). I'd also suggest doing the bumpers if you're having any paintwork done.
I use struts on the plastic rear hatch but not on the bonnet (don't think there's provision for it on mine, but I didn't like the thought of them exerting a constant upwards force anyway), I carry a piece of wood for that duty [
The bonnet need only cost about £145; the hatch will be a good deal dearer though. I have a polycarbonate 944 hatch that I intend to sell at some point, although that wasnt the purpose of my posting.
I have a speciallly trimmed broom handle for my bonnet.....[
]
ORIGINAL: Peter Empson
..... They do tend to spin in a straight line quite neatly though [
That was certainly Andy Prill's experience when racing a GT40. [
]What ever the reason, I agree with Peter that a 944 is one of the kindest cars to go sideways in. Loosing weight could change this to some extent but is perhaps unlikely (without a complete strip and hole saw job) that you could make it too bad.
Peter Empson
PCGB Member
I'm aware there are plenty of cheap fibreglass ones about, but add the cost of painting it properly so it doesn't look like a race part and it's still going to be a relatively expensive job. Is it a Pro-9 piece you're suggesting? I ask as I haven't heard anything positive about their panels yet (but should add I have no personal experience of them).
Neil Haughey
New member
Some good advice here from 944 man. I am looking at all these things as part of my long term plan and one has to look at composite bonnet and wings because like we have said it is easy to shift one heck of a lot of weight from the cabin and backwards. The bonnet and wings would also be eligible for racing.
ISTR most of the 20 lb weight in the sunroof is not the cover itself i.e. you can gut the panel and loose something like 15 lb in weight. Peter can you confirm this? This brings into question just how much weight is up there in the headlining. Welding in a steel panel or bonding in a CF panel would also stiffen the car in an extremely important area.
Stock exhaust system and catalytic converter are both amazingly heavy. I struggled to carry my rear section it must have weighed a good 25 to 30 Kg, and the catalytic converter felt like a good 15+ kg as well. Anyone have the accurate figures on these?
Starting from the top and ends of the car has to be the best approach once the easy stuff like seats are out. My battery is stuffed so I have bought a braile lightweight one from edo performance, this saves 12 kg on its own and only costs a little more then a stock battery.
In a race car a fair bit extra will/would be going from the front end of the car when the headlights and heater are binned (afaik rules say adequate ventilation, nothing about having hot air blowers to your feet or side windows but I have only skim read the blue book once thus far so please correct if I am getting carried away!).
Interestingly all the electrical goodies such as mirrors and windows don't really weigh that much more then the manual equivalent, I blame the CS for putting this idea out there but like Peter says it adds up.
ISTR most of the 20 lb weight in the sunroof is not the cover itself i.e. you can gut the panel and loose something like 15 lb in weight. Peter can you confirm this? This brings into question just how much weight is up there in the headlining. Welding in a steel panel or bonding in a CF panel would also stiffen the car in an extremely important area.
Stock exhaust system and catalytic converter are both amazingly heavy. I struggled to carry my rear section it must have weighed a good 25 to 30 Kg, and the catalytic converter felt like a good 15+ kg as well. Anyone have the accurate figures on these?
Starting from the top and ends of the car has to be the best approach once the easy stuff like seats are out. My battery is stuffed so I have bought a braile lightweight one from edo performance, this saves 12 kg on its own and only costs a little more then a stock battery.
In a race car a fair bit extra will/would be going from the front end of the car when the headlights and heater are binned (afaik rules say adequate ventilation, nothing about having hot air blowers to your feet or side windows but I have only skim read the blue book once thus far so please correct if I am getting carried away!).
Interestingly all the electrical goodies such as mirrors and windows don't really weigh that much more then the manual equivalent, I blame the CS for putting this idea out there but like Peter says it adds up.
Have a look at GRP/Carbon replacement body panels, polycarbonate windows, trim removal, carbon brakes, magnesium wheels, alloy fasteners for non-stressed fittings, titanium or radiused fasteners on stressed fittings, swaging steel panels, drilling steel components and bracketry and attention to detail.
The removal of sound deadening and sealer is hard work but saves loads of weight! []
The prospects are only limited by your energy (and budget)! []
Regards,
Clive
The removal of sound deadening and sealer is hard work but saves loads of weight! [
]The prospects are only limited by your energy (and budget)! [
]Regards,
Clive
Peter Empson
PCGB Member
I don't have the weights to hand, but the sunroof is very heavy even when stripped, the lining weighs next to nothing on it. Converting to manual latches is a good start so you can get take out the motor, but getting rid of the whole thing is the best way to go.
Neil Haughey
New member
Peter did I read before that you have had a panel bonded in? could I be so rude as to ask how much this cost?
Peter Empson
PCGB Member
It didn't cost that much in the grand scheme of things, I don't have an individual figure as Simon did me a cracking deal on a few pieces at the same time. It was made by GT Racing so I imagine it'll be quite a bit dearer now thanks to the exchange rate, the carbon one is currently listed at $456 on their site.
Neil Haughey
New member
Cheers Peter
berg944
New member
My Turbo has no Sunroof, Air Con or ABS.
I will keep the electric windows because it gets rather warm.
I had a thin rear carpet but I have changed to the heavy thick carpet as I do not track my car.
I might change the exhaust, I could not believe the weight difference when a did the Lux exhaust.
I put my car on the scales with carpets, spare wheel, tools, rear seats, 924 none electric seats, stereo with 4 none Porsche speakers and 1/4 tank of fuel.......
1260 kg
What is the weight and spec of your cars?
Mike[:'(]
I will keep the electric windows because it gets rather warm.
I had a thin rear carpet but I have changed to the heavy thick carpet as I do not track my car.
I might change the exhaust, I could not believe the weight difference when a did the Lux exhaust.
I put my car on the scales with carpets, spare wheel, tools, rear seats, 924 none electric seats, stereo with 4 none Porsche speakers and 1/4 tank of fuel.......
1260 kg
What is the weight and spec of your cars?
Mike[:'(]
sawood12
New member
I think the only way to get significant amount of weight out of our cars is to strip to bare shell and only put back what is absolutely and utterly necessary - the very minimum you need to drive the car. You can remove elecy window's, A/C and all the other electrical gubbins, but what about the wires in the wiring loom and all those terminals and large fuse box, what about all the enigne stuff that is there for the purpose of the environment such as the vapour purge. There is a hell of alot in our cars which is not necessary for a track dedicated car, but you can't get at it without stripping the thing apart. Also once you get rid of all the electical gubbins you can fit smaller and lighter alternator and a smaller battery
Also it often amazes my why people with track dedicated cars still retain the dashboard and stock fan and heater system. Surely a few aftermarket gauges bolted onto the bulkhead and an aftermarket racing fan unit will save a hell of alot of weight. The amout of wiring and gubbins behind the dash must weight a good few KG's.
I guess it is pointless chasing a few KG's and alot of money on carbon fibre body panels until you've been as drastic as this. Reading on Rennlist I get the impression that there isn't as much as you'd expect to be saved with a Carbon Fibre bonnet, and less to be saved with carbon fibre wings. Spending a grand to save 20kg's out of a 1300kg car doesn't make much sense and isn't going to transform the cars performance at all. It's icing on the cake stuff.
Also it often amazes my why people with track dedicated cars still retain the dashboard and stock fan and heater system. Surely a few aftermarket gauges bolted onto the bulkhead and an aftermarket racing fan unit will save a hell of alot of weight. The amout of wiring and gubbins behind the dash must weight a good few KG's.
I guess it is pointless chasing a few KG's and alot of money on carbon fibre body panels until you've been as drastic as this. Reading on Rennlist I get the impression that there isn't as much as you'd expect to be saved with a Carbon Fibre bonnet, and less to be saved with carbon fibre wings. Spending a grand to save 20kg's out of a 1300kg car doesn't make much sense and isn't going to transform the cars performance at all. It's icing on the cake stuff.
Peter Empson
PCGB Member
That's a really good figure Mike, in fact I'm really quite surprised at that! I'm looking forward to the weigh off if it happens this year (not that I expect mine to be especially light, it has too many extra heavy bits now).
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