Setting up a Superlight properly.......

[caseyc]

As I have a Superlight 1.6 and haven't paid too much attention to it's setup, I figure it is about time I did......as a complete non-techie (I figure you can only do one thing properly and I would rather concentrate on driving rather than mechanicals wink.gif) can someone more clued in guide me in the right direction......

 

Tyre pressures.....I have CR500s on the standard Superlight rims - what would be a good starting point for road use, and for track use?

 

Camber/suspension.....I have trouble understanding tyre pressures - so this one really gets me confused. Having had the current setup checked very briefly by Hyperion at a recent track day they tried in vain to explain what those adjusting things do. Can anyone tell me in idiot's language what if any settings changes I may need to make from time to time?

 

Tuning.....as my R500 is likely to end up waiting till next year I'm starting to wish the Superlight had a little more power (100+BHP increase would be nice wink.gif), are there any simple and chgeap upgrade options? It's devastatingly quick, but just lacks that mid range grunt and I get annoyed at not being able to overtake as easily as I could in my TVR - in fact it's often bloody impossible to overtake even a standard repmobile at 50mph on a B-road safely sad.gif

 

Cheers for any help received......

 

Casey

 

 

 

[Red SLR]

Pressures : not 100% sure, but I think mine are 15psi

 

Setup : John Noble set mine up for track use, dont know what he did but took ablut 1/2 an hour and laser boxes etc.

 

Mods : Nothing (as I have discovered) is cheap. The only mods that will get you decent power increase are Throttle Bodies and ECU and cams. That is still going to set you back atleast 1500 quid even if you do all the work yourself.

 

There you go then, clear as mud.... Mike!

 

Simon.

 

X777CAT

[WillPaul]

Casey

 

I too have a 1.6 superlight and like you would rather spend time driving it than seeing it being operated on in surgery!

Camber/Caster I can't tell you a lot about. The other thing you miss out is ride height - this is perhaps the simplest way to change the handling of you car on-site to suit changing track conditions. In very basic terms (the only ones I understand ;-), raising ride height at the rear induces more oversteer/reduces understeer, lowering it reduces oversteer/increases understeer.

Re engine mods: I'm surprised you're having trouble overtaking repmobiles. Sure you're using the accelerator properly? ;-) Only kidding. If you want an additional 100bhp from your engine, you're going to have to undertake some serious work, including porting and flowing the head, big valves, new cams + ECU, throttle bodies, plus strengthened pistons, liners, crank etc etc. If you really do want 240bhp, it'll cost you about GBP6k - 7k. Not cheap.

The other point is that I think everyone who has reached these sorts of power levels has done it on the basis of a 1.8 engine. Anyone know what's the max that's been got out of a 1.6??

 

Mike? Peter?

 

Cheers

 

will (also a non-techie)

 

Edited by - WillPaul on 13 Dec 2000 22:30:48

[Mike Bees]

Mine gave 200bhp as 1.6 but that was before the head was fully ported. Now as a 1.7 with the head completely worked it's close to 240. If it was a 1.6 it would most likely give the same power but further up the rev range.

 

Mike

[caseyc]

>I'm surprised you're having trouble overtaking repmobiles

 

When you have been used to a Griffith overtaking in anything else seems downright dangerous. Griffith 50-70 time was 1.1 seconds....allegedly (but it did feel that fast) - my Superlight just doesn't have the pull.

 

I'm not too interested in doing major surgery, just if there was a simple bolt on or two that would help the engine a litlle I wouldn't be adverse to making the changes - I I think porting/flowing/polishing/etc is a little beyond current aims.

 

Ride height is something I forgot - told you I'm not a mechanic. That would be something to do with those locking things on the suspension.....

 

Tyre pressures - 15! At the track day the Hyperion engineer put them on 20/21 inside/outside......too much or just the conditions?

 

Casey

 

 

[Mike Bees]

There is no simple bolt-on to 1.6K Supersport (or pretty much any other engine really) that will yield a substantial gain. A throttle body/ECU change will probably get you 10-15bhp, but it depends on just how simple you mean by simple.

 

Mike

 

PS - Hope your head gasket is holding up wink.gif

[WillPaul]

Re tyre pressures: I run my car on Yoko A032s - general (cold) use at 17psi or on track measure at 21psi when hot i.e. as quickly as possible after coming off track.

 

Mike your engine is based on a 1.6 block? What of the cylinder head? Is that now a totally new item? What say you of a straight change of ECU, from Rover MEMS, as I currently have, to Emerald? Apart from future mapability (as & when TBs etc) would it give any other benefits on its own?

 

will

[Peter Carmichael]

will:

What say you of a straight change of ECU, from Rover MEMS, as I currently have, to Emerald? Apart from future mapability (as & when TBs etc) would it give any other benefits on its own?

---

 

Will, your MEMS ECU is just plain wrong. It is a faulty part and you should have kicked and screamed to get it replaced under warranty. (Will's engine has the soggiest K-series throttle response of all time, which was instantly cured by swapping on my Emerald ECU).

 

A mappable ECU will allow you myriad ways of getting the engine set up incorrectly. The answer is to have a proper rolling road set up, but having a good idea of your objectives before you even get that far helps. Used in this manner, the Emerald can be used to fix faults in the mapping, as currently delivered by the MEMS. Over and above a properly working MEMS I would say it offers no advantage. Compared to your current MEMS the advantage is huge and the system is entirely auditable so there is no scope for creeping decay in the setup - you can diagnose broken sensors, etc.

 

Mike your engine is based on a 1.6 block? What of the cylinder head? Is that now a totally new item?

---

 

Apologies for jumping in. There are no differences between the 1.6 and the 1.8 block apart from the crankshaft and rods. Indeed, my 1.8 started as a damp linered 1.4 - same block but different pistons/liners too.

 

Mike has always sought to compete in the under 1700 speed classes. The starting point of the 1.6 wasn't a bad one. First attempt (1998?) with hot cams, a VVC head converted to solid cams (but little or no porting) and forged pistons gave 200bhp @8000rpm, with more to come. A bottom end rebuild for 1999 brought a custom billet crank and steel rods and a change in capacity to 1688cc - same head. This brought the power down the rev range, but also beefed up the torque delivery (probably exhaust pulse tuning). I think this gave 207bhp @7420. The engine was also now *safe* to rev past 8000. For 2000, Mike had Dave Andrews sprinkle some magic dust on the same VVC head - Mike's and my heads are modified to the same spec apart from cams.

 

I think Mike moved from GEMS to Emerald ECUs half way through 1999.

 

The important thing to remember is that the head spec determines the power potential for the engine. From 1588cc upwards, the k-series uses 80mm bore and allows the same valve area to be developed in the head. Whether these valves can be opened with an aggressive cam profile depends on stroke. The valve/piston clearance needs to be checked with shorter strokes.

 

With the same head and a shorter stroke (smaller capacity) the power moves up the rev range. The piston accelerations at these higher rpm are not much different, but the valvetrain acclerations are higher, giving the real risk of valve float and getting close to the limitations of toothed belt drive for the camshafts.

 

Edited by - Peter Carmichael on 15 Dec 2000 00:48:34

[Peter Carmichael]

B****r. I got drawn into the power debate - it is so easy to derail a setup thread by mentioning engines.

 

I have a basic philosophy for setting up my Superlight:

 

1. Get the front close and then leave it alone.

2. Fine tune on the rear ARB and rear ride height.

 

What is right will depend on tyres and I have no experience of CR500s. Neither does anybody else so there isn't an answer you can dial in, but if you follow a structured approach you can get it spot on without too much sweat.

 

The approach I used was to bracket the *ideal* setting by changing the most awkward setting least of all but, having made a change, progressively work through other easier changes until the best combination appears. With a Superlight you have a really good starting point with all the basic components being good enough - this means that you don't have to worry about springs, dampers or anti-roll bars.

 

The adjustments you have are:

 

Front: Ride height, camber, castor, toe, tyre pressure.

Rear: Ride height, ARB, tyre pressures.

 

The front geometry is all interrelated so it is worth eliminating items from consideration. First set a sensible ride height and leave it there - make sure you have about 10mm free travel on the dampers before the bumpstops come into play. Second, after any other changes set the toe to straightahead - it won't be drastically wrong there. A cold tyre pressure of 16-17 psi won't be far wrong. Castor of two washers each side of the wishbone leg won't be far out. Darn! All we have left is camber.

 

In essence, what I am suggesting is that you change camber in stages and at each stage, spend a bit of time mucking about with the rear ARB (full soft and next up on each side are probably the only viable settings) and at each ARB setting you muck around with the ride height (start low and the car will try and plough on - raise by two turns at a time until the car feels edgy and nervous).

 

The camber will affect the feeling of *bite* that comes through from the steering. I suggest that you start with too much and reduce until it is difficult to feel what the front end is up to. 2.5 degrees is probably the starting point.

 

Hopes this helps. It took me two years to distill it down to this...

[Graham Sewell]

As far as overtaking safely is concerned, I do not understand the 'requirement' for more 'power'. As far as I can tell, a basic engine configuration will supply a given max power at a given engine speed. The route to more power is normaly to increase the max engine speed safely.

 

However, for overtaking, one rule of safety is not to change gear during the manouver (sp?) and this become difficult with a revvy, peaky engine (and close ratio box).

 

So what is required is a broad torque band so that the overtake can be started at lower revs and therefore not need a gearchange. This is something that I would imagine a TVR would do well, and a Seven would not be as good. There is no real substitute for a larger engine.

 

Don't get me wrong, I love my Seven on a country lane, but overtaking is always a risky business and opportunities need to be assessed carefully to avoid bending metal. I remember John Lyons once telling me that the hardest people to overtake are those who are driving between 50mph and 60mph as very few cars accelerate well in this range to get a suitable approach speed after committing to the overtake.

 

Just my tuppence worth...

 

Cheers,

 

Graham

 

 

[Paul Ranson]

> However, for overtaking, one rule of safety is not to change gear during the manouver (sp?)

 

Why?

 

> and this become difficult with a revvy, peaky engine (and close ratio box).

 

With a close ratio box you are more likely to have a gear that can take you past.

 

I reckon that with a standard Superlight 1.6 on ACB10 and using 5000-7600rpm you have 43-65mph available in second, 54-82 in third and 65-99 in fourth.

 

Any likely peakier engine will still be on cam by 5000, and will still be going further up the rev range, so you go faster and for longer, IYSWIM.

[WillPaul]

Peter - thanks for your comments. You are absolutely right, I *should* be kicking and screaming under warranty, but being relatively time poor, and knowing that at some (as yet ill-defined, but certainly 2001) point in the future I will be binning the supersport kit anyway, I have taken a conscious decision to move on to the next step rather than fight with Caterham to get a new MEMS that I will get rid of certainly within the next 12 months. If you see what I mean.

Re mapping, I would *definitely* have it properly mapped on a RR anyway - simply wouldn't know where to start if I were to do it myself ;-)

will

 

Edited by - WillPaul on 16 Dec 2000 10:49:40

[Peter Carmichael]

Will - The other starting point is anybody's existing map for a Supersport. Dave Andrews keeps a library but IME he doesn't have anything that is quite there.

 

The comment regarding knowing what you are after at an RR session is related to:

 

Do you want to run lean/stoic until 2/3 throttle and then ramp up to 12:1 by full throttle? - this gives the fuel economy you are used to and full power is just a matter of using more welly. The downside is that transients can be more difficult to get right, with a significant requirement for acceleration fuelling - very difficult to get right on a RR.

 

IME, a good rolling road session still leaves some questions to answer. Knowing what has and hasn't been mapped on the RR is critical in judging how to make ongoing refinements.

[Alastair Brown]

Paul - changing gear in the middle of an overtake increases the risk of the overtake. A missed gear would be a bad. If you are in the middle of a gear change an the situation changes unexpectedly (the person being overtaken swerves for example) you could find yourself unable to take avoiding action. Finally changing gear is a distraction in the middle of hazardous manouver, where all your concentration should be directed to what is going on around you.

 

Phew, lesson over. Consult Roadcraft for further details. Or Hugh at Cadence, John Lyon or a myriad of others.

[mark.hall]

I would have thought running out of steam before you are past would also be dangerous. Gearchanging shouldn't be a conscious thought process, and therefore shouldn't distract you that much, missed gearchanges notwithstanding of course. A gearchange should be a natural thing, part of the "feel" of the situation as much as any other part of driving. The other guy swerving or the situation changing is not affected by your actions, only your reaction to it. You should still have one hand on the wheel (I would hope!), and both feet able to accelerate or brake, or dip the clutch, and one hand on the gearstick already, so all is far from lost.

 

[Paul Ranson]

> changing gear in the middle of an overtake increases the risk of the overtake. <

 

You haven't defined 'overtake'....

 

I think it is not a requirement to continue accelerating for the entire manoevre, so an upshift may be safe. Gear shifting should be unconscious, and if a missed upshift would create a risk in an overtake then you are cutting it too fine.

 

Paul