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Discussion Starter #1
Following on from this thread.

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The reason why I raised the subject of Aerodynamics was that I feel, if your going to put 400bhp through the front wheels you need to make sure that the wheels are being pressed into the tarmac under acceleration. Otherwise all that power will just end up as so much shredded tyre tread. That way, although you still won't be able to carry as much speed into a corner as a seven, you'll be able to make up plenty of ground on the exit.
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Um - traction problems are not an occurrence at speeds high enough to matter for any kind of downforce you can create with a road going car.
Typically, the front wheels are scrabbling for grip when coming out of a low-gear corner. So you're still looking ito ways of improving mechanical grip. 400 Bhp could make things slightly different, but I doubt you could make them driveable in any roadgoing FWD configuration. Creating a somewhat balanced driving experience with 300+ hp and FWD will already be requiring some serious thought into smoothing out the torque curve and extending it towards higher rpm (that's where the 2.0 litre engine as a base to work from comes in) instead of just turning up the boost even higher. The Focus RS, for instance, has enough problems with 215 turbocharged bhp because of the way the power comes in. I'm afraid it's either AWD (with the inherent disadvantages of weight, response, and on-limit bahaviour - the latter goes for limited slip diffs, too IMO) or tweaking the engine response and torque curve with some sympathy towards the rest of the chain.
Because of how much you rely on mechanical grip at the front end when you set your sights this high the double wishbone set up of the Classic 900, which allows for quite radical camber adjustments to boot, is still the ideal. According to my sources there's still a big improvement to be made in transient response and understeer when cornering very hard, with polyurethane wishbone bushes replacing the stock ones, and that is what I am going to do.
Furthermore, you want to keep weight down without stripping all of the interior. Undoing a Saab from it's practicality and ability to haulfour adults and their luggage in relative comforts would kind of defeat the object - if you want to go that far, why not get a Caterham or TVR right away? So the aim is 'intelligently' removing weight without compromising safety, practicality or the car's interior. This for instance means I don't remove the boot floor, but rather raplace it with lightweight material (of course, this does tend to make things more expensive, but then again you end up with car that you can still use ).
Which all helps to define a more 'realistic' goal for our cars. The pipe dream is something like 330 hp and 1,100 kgs. I don't think that 300 hp/tonne will be quite attainable, but it gives you something to strive for  . 300 hp and 1,200 kgs for a 250 hp/tonne ratio might be closer to reality - and still would put you somewher d*mn close to the supercar stratosphere...  [/b]
I think Erics points above are a good staring point. As we all know he's pouring his whole essence into his Saabine project. So, who out there is planning to create an uber Saab for trackdays and how do you plan to embarass the sevenesque and AWD rally-bred elite?

Um - traction problems are not an occurrence at speeds high enough to matter for any kind of downforce you can create with a road going car.[/b]
Well I've seen some Quattro's with b***y big front scoops at the Curborough sprint days. Boy those things were positively nailed down, it has to be said many of them probably weren't road legal. However, making a car illegal for road use is no problem providing you have another car and a trailer. I personally would have no problem gutting all the comfort factor out of my CD once I had something to replace it.

Hmm, air con or an extra 2 tenths off my 60 - 100 time. Not a tough one for complete speed freaks to answer.
 

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This one could run... but to pick up an earlier point that Eric made about LSD's, I have to say that since I've had mine fitted it makes things a lot quicker, although I do agree it requires more skill to drive, especially in the wet. A conventional diff will simply "lose" the wheel with least traction, normally the inside one on corners. If you boot an LSD too hard, however, you'll lose both wheels
which is bad news indeed. I'll admit I nearly came a cropper a couple of times before I got used to it.

With practice in the wet at Goodwood I found that I could moderate the throttle suffiently well to get a comfy balance of sufficient power to get out of the corners quickly with a very gentle oversteer slide. Not easy I grant you, but it can be done.

What surpised (and delighted) me most however was the difference to performance in the dry. Coming out of corners the LSD is simply awesome, and really knocks back underster, hugely tightening the line out whilst avoiding lighting up the inside tyre. It also feels a lot more responsive through twisty A roads at speed.

I think the point I'm trying to make is that in the world of compromise that we live, I accept that my car (like most) is not built for the track- and I think you would agree that when it comes to wringing the last bit of performance out of a car it's not unreasonable to expect the driver to have to put some skill and effort into it at the limits rather than let the car do all the work (oh, sorry BMW M series
).

In fact, I'd go so far as to say that I don't want a car with ESP, ASC, whatever all these gizmos are called if I'm going to take it out to enjoy driving it- because for me the enjoyment comes from pushing both mine and the cars's abilities. Strip all these "stability" toys off and you can actually feel what's going on at the road and react accordingly. Use them and by the time you realise something's amiss, it's probably too late...

But can I keep my ABS, please?
 

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Air con is for whimps (at least, in our climates) Saabine never had one, and I sure as h*ll ain't adding one! Another nice thing about Saabine is that she started off as an 8 valve turbo and hence does not have a sunroof as standard equipment - IIRC all 16 valve turbo's have electric sunroofs, at least in the markets I'm aware of.

I think, however, that the rationale (as if you ever could call such a project rational) behind spending a lot of time and money on a fast road/track day Saab is that you can make something that you are able to enjoy most, if not all of the time, be it because of an actual transportation need or just because I want to drive the thing for the heck of it. I could spend like a hundred times the money on an exotic and find myself not driving it when it rains, on bad roads, when I have to do some serious mileage on a day or when I have to transport more than myself, one passenger and two toothbrushes. Losing that ability with a Saab would IMO defeat the object to an extent. That's why I stop short of fitting a rollcage. Kind of silly to have four doors and a hatch when there's nothing more than pipework behind three of them...

And if I ever start a family, I'll have the fastest and most charismatic family car you can imagine. Just think of it - blasting the doors off TVR's and Porkers with a child seat still strapped to the rear seat.

On the 'latest Saabine developments' front - looks like I might be able to fit a custom programmed DI system (from Sweedspeed's former racing 900) - Frank will be looking into the matter in the course of next week. He sees no problem bolting a trigger for the DI's crank position sensor to the crankshaft, without lifting the engine It would mean total control over ignition timing vs. rpm and boost pressure, and some kind of knock protection in case the water injection system or the 5th fuel injector should fail - something I was kind of worried about...
 

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I would have thought that at a venue as tight as Curborough the Quattro's 4WD and slick tyres are the key contributors to it's glued-down-ness rather than aerodynamic aids.

Personally I don't see a Saab as a particularly good starting point for a track-day car, but then I'm one of the 7 brigade

Mind you a 9-5 with the same power to weight ratio as my 7 would be fun on the road, although I'm not sure the gearbox would cope that well with over 700bhp.

Mike
 

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Well, I absolutely agree an LSD makes things quicker - but I feel I am not good enough a driver to get comfortable with it. If most of the time I'd drive on an airfield-type tracks with smooth tarmac and large run-offs, I would not heasitate adding it - but my car will still do most of its miles on the road, and the margins for driver error on the 'Ring (which is by far the most 'accessible' track from here) are wafer thin. Now I can come out of a corner under full boost with the inside wheel slightly(!) spinning but the car holds its line tenaciously on the outer, and I have no prbolems whatsoever with torque steer on broken road surfaces, off-cambered roads, et cetera.

It's allabout priorities - I want to have quality of information through the steering, as well as a sense of security when the going gets rougher, and I accept a trade off in terms of sheer speed when exiting a corner. I think of Saabine more as a kind of 'grown up' hot hatch (<1,200 kgs, shortish wheelbase, relatively high levels of mechanical grip from modestly sized tyres) - something very agile that you can carry a lot of speed into a corner with, and still is relatively kind to the less advanced driver. With a 9000, you generate a lot more momentum by means of its weight, wide track and sheer low/midrange grunt, and it has McPherson struts rather than double wishbones, so a way of channeling all that thrust though the front wheels is more of a priority I'd wager to think.
 

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Discussion Starter #6
Air con is for whimps  (at least, in our climates)[/b]
Well mines just so much dead weight at the moment, until my resistor pack eventually shows up anyway.

My plans are basically to buy a newer car when I have a bit more money, then strip down the CD to the minimum necessary for it to be driveable! It will no longer be a nice comfortable runabout, as I will have a nice new Saab to perform that function, although I may have keep the CD road legal so I don't have to pay for track days just to get some practice driving the thing. I'd also like to install a roll cage if I can do so, the cars going to be very very fast with no weight, even before I start buying the equivalent of a Stage 5/6 kit to slap in it's engine bay. Of course I don't plan to drive upside down (
) I would like to be protected against every eventuality.

And if I ever start a family, I'll have the fastest and most charismatic family car you can imagine.  Just think of it - blasting the doors off TVR's and Porkers with a child seat still strapped to the rear seat.    [/b]
Yep, as Bill found, astounding the big boys certainly provides a massive feel good factor. But personally ... I wanna a 9000 race car!! Something that looks flippin quick, goes even quicker and annoys the hell out of Scooby STi drivers.

Then there will be the small matter of learning how to drive like a race driver so I don't end up looking like a pratt ... again.
 

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Personally I don't see a Saab as a particularly good starting point for a track-day car, but then I'm one of the 7 brigade  [/b]
Well - your 9-5 weighs 1,600 kgs and my slightly stripped c900T 1,200 - that makes one heck of a difference in terms of momentum that needs to be kept in check... For one thing, a lower kerb weight allows you to concentrate on extending the torque curve towards the high rpm range instead of adding ever more torque, because the car's torque/weight ratio is already very favourable for a four-passenger tintop.
Remeber -it's not horsepower that breaks the traction from your front wheels, corrupts your steering and ruins your gearbox - it's brutally produced, turbocharged, low/mid rpm torque.
Key of making an ultra performance Saab with good driveability characteristics is trating it more like you would with tuning a normally aspirated car - something that is mentally not so easy because in the beginning, you tend to seek the instant gratification that turning up the boost sky high (lots of low/midrange grunt, running out of puff higher up the range gives you.

I thought about adding a Westie to the stables sometime when I'm slightly less poor (and likely a fair bit older!) but the jury's still out on that one. Over here on the continent, there's no such thing as a trackday scene so you're always driving several hundred miles to reach one (I am sure eating at least half a day's worth of motorways in a Seven, just to be able to do a few brilliant laps on a track, then having to cop with the thing all the way back would deter me from it quite quickly) and likely carrying overnight bags. Due to the lack of decent weather protection (yes I know they have hoods, but it takes about an hour to fit them, and it gets very claustrophobic inside for someone 6'3" tall!) and general practicality the car would likely only come out for Sunday morning blasts and would turn in an expensive indulgence for it. If I ever afford myself a second toy, it therefore more likely would be something like a Chimaera or a TVR-engined MGB V8 conversion...
 

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how about lighter than a 900 with a shorter wheelbase but retaining the classic double wishbone with a blueprinted 240 hp plus (claimed)

its a ....99 with a turbo 16 engine

I will be checking it out this week

and its cheep
 

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Originally posted by Bubbles (fka Mark E):
[qb]If you boot an LSD too hard, however, you'll lose both wheels    :eek:    which is bad news indeed.[/qb][/b]
I also did this the day I drove Mark's car in the rain, to his endless amusement


I think I'm comfortable enough now with the 9000's handling to try to learn something new, so the Aero is currently at Abbott Racing in bits. Later this week, hopefully, I'll have a racing clutch (clutch slip being the initial reason for removing the gearbox), LSD and lower final drive. And the very first poly transmission mount for the '94-on gearbox, if it arrives in time.

Hopefully, this will address some of the shortcomings I found on the track. The standard Aero gearing is unnecessarily high for most circuits. However, the real shortcoming is the brakes, which would have been my next upgrade had the clutch not failed. Soon...

I do like the massive torque curve of a modified Aero. However, unlike other tuned 9000s, the Aero's turbo allows a lot more boost higher up the rev range so it doesn't run out of steam too much. Mark's enormous turbo should be even better in this department, once he has an ECU and fuel delivery to match.

I really like the idea of driving a standard-looking, large executive car round the track, sitting in my big leather seat with the air-con on (sorry, Eric ), blasting past expensive, "serious" sports cars and even showing some of the track-day-specials a thing or two. Eventually, I'll probably want to shed some weight to make the car faster and more nimble at a stroke. I like Eric's approach to this - removing the weight where it won't show. I fear I'd have more work to do than him, though.
 

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how about lighter than a 900 with a shorter wheelbase but retaining the classic double wishbone with a blueprinted 240 hp plus (claimed)

its a ....99 with a turbo 16 engine[/b]
Sounds like massive fun. Like for like, there is not much between the 99 and the 900 for weight (about 20 kgs), but some say the 99's front end is appreciably stiffer due to the A-pillars extending down to the wheelwell. On the flipside some work on the wheel geometry might be in order to cut back on understeer which was always more pronounced with the 99 than it was with the 900. But then again, this car might already have the 88- on 900 hubs and axles retrofitted for the sake of better braking and wheel selection, like several 'hot' 99 conversions before it...
 

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Re: weight saving - a few ideas from Project Saabine (a lot might be obvious, but still...)

* Removing space saver spare wheel: 11.5 kgs
* Removing tool kit: 2 kgs
* Removing rubber/foam sound proofing mat under carpet: 8 kgs (likely more in a 9000 ). If you want to retain (near-)standard NVH levels, replace with Dynamat Dynaliner (available at 'serious' car audio outfits) which weighs a scant 0.39 kgs per square meter instead of ~5
* Replace rear electric window lifters with manual lifters: 2.18 kgs per side
* Replace stock 60A battery (16.1 kgs) with Optima Red Top gel battery (which can be placed everywhere in the car, in any position as a bonus and weighs 14.9 kgs)
* Bolt plastic license plate frame directly to front bumper, deleting metal underlay (0.37 kg)

...
 

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Some of it was indeed obvious, but...

Originally posted by Eric van Spelde:
[qb]* Removing rubber/foam sound proofing mat under carpet: 8 kgs (likely more in a 9000     ). If you want to retain (near-)standard NVH levels, replace with Dynamat Dynaliner (available at 'serious' car audio outfits) which weighs a scant 0.39 kgs per square meter instead of ~5[/qb][/b]
I had thought of removing the sound insulation, but thought I would just have to put up with lots of noise. That sounds like an excellent idea. There's quite a bit of insulation in the doors and tailgate too - a few more Kg at least. Probably some in the roof too, although I believe the headliner is a bu66er to refit.

Unfortunately, no 9000 variants came with manual windows, so I don't know whether there are any mechanisms that would fit. Still, that would start to violate the principle of keeping it looking standard.

If I could save roughly 80Kg to start with, that would at least compensate for the weight of an average passenger.
 

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Unfortunately, no 9000 variants came with manual windows, so I don't know whether there are any mechanisms that would fit.  [/b]
I believe some of the earlier (upto 1990ish?) lower spec cars came with manual rear windows - I certainly took an advert for a car so described when I was editing the SEC mag. Might be worth a trawl of scrapyards.
 

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Yep, sorry - I was talking about the rears. With all kinds of toll booths and the pass scanner at the entrance of the company parking lot, electric front windows are actually nice to have...
 

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Bill, one of the best ways to save weight on the fully loaded 9000 is to ditch the electric seats- IIRC that will get you at least 30kg.

As we've discussed privately before though, I'm wary of taking too much weight off the rear end- it has enough tendency as it is to step out when you don't want it to!

If I decide I'm going to get really serious about this track stuff though, the first thing that must go is the aircon. I'm worried as it is that I'm going to have difficulty keeping things cool under the bonnet. Since fittign the High flow intercooler, sumemr running temps have significantly increased as it's obviously keeping more cooling air away from the coolant radiator.

I'm currently investigating some sort of ducting arrangement to get more air to the rads as the bumper obscures over a third of the available cooling area, and am also considering fitting a preformance electric water pump- especially after the revelation that the standard one cavitates above 5000rpm.

And you'd also save a good few kgs off the front losing the aircon...

Just a thought... if you don't need em, why not just simply remove the rear window motors and leave them locked shut?
 

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Just a thought... if you don't need em, why not just simply remove the rear window motors and leave them locked shut?  [/b]
In the 900's case, it proved easier and probably just as light fitting the manual regulators versus devising a way to keep the windows shut - even should some b*gger try and use some force to open them from the outside.

OK, they can always smash the window in of course, but that at least is likely to attract unwanted attention in most cases...
 

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Originally posted by Bubbles (fka Mark E):
[qb]if you don't need em, why not just simply remove the rear window motors and leave them locked shut? [/qb][/b]
Yep, I thought about that. And I thought about the air con too. I suppose as the Aero creeps towards being more of a track day "special", I'll start removing unnecessary functionality from it, perhaps even including the Aero seats. I'm pretty sure a velour set with manual adjustment (like those in my CSE) would be a lot lighter. I find them more comfortable than the Aero seats anyway and they give better lateral support.

I'm very keen to keep it looking like a standard road car, as that's part of the fun for me. For the moment, I'll probably start with the things that will neither show nor reduce functionality, as the Aero is still my main car.
 

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BTW - both the velour and leather-clad "Contour" pattern 900 seats weigh about 14 kgs, with no discernible difference between them. Which means siginificant savings from that could only be achieved using fixed-backrest racing buckets, as most aftermarket 'recliner' sport seats are in the same ballpark as the OE Saab seats - in fact quite a few, even manually-adjusted ones, are heavier than that.
 

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Originally posted by Eric van Spelde:
[qb]BTW - both the velour and leather-clad "Contour" pattern 900 seats weigh about 14 kgs, with no discernible difference between them.[/qb][/b]
I suspect the Aero seats, being bigger and electrically-adjustable, though, would weigh a lot more.

I only mention velour as they are grippier and I have a set in my other car. If I don't want to mess with that one, then I imagine a set of velour seats would be a lot cheaper than leather ones.
 
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