OliverSedlacek

I've dialed out the bump steer on my car and also did a couple of cars for a couple of mates. I made my own rig to measure bump steer as it's really pretty simple. The best shim thicknesses (to raise the rack) came out at 5.5mm, 2mm and 1.5mm for the three cars, reflecting the fact that Caterhams aren't always built to the tolerances expected of modern mass produced cars.

Caterham presumably chose to err on the side of 'toe in on bump' as it's considered safer. This is why in general the racks always need raising, never lowering.

Dave Gemzoe is a top bloke! It's amazing what you can see if you know what to look for. The verdict is that the cam wasn't hardened properly.

Dave Gemzoe has volunteered to come over and offer an expert opinion.

Thanks for the info Roger. I've put photos on a blog posting as that seems the easiest thing to do on this website. The cam and followers were fitted less than 4000 miles ago. The cam manufacturer explicitly gave instructions to just run the cam in using normal gentle running. The profile is around 295 degrees and the springs are VS7 with standard ratio roller rockers. With hindsight I regret not fitting a new gear to the oil pump.

Who produces cams ground from new blanks these days?

So I've lost another camshaft on my crossflow. As before, it was the inlet lobe on number 2 cylinder. Can anyone suggest why I should be having problems with just this one lobe? The engine is dry sumped and distributorless in case that makes a difference.

The fuel gauge works the other way round on an XFlow seven. Full scale corresponds to maximum sender resistance so you've probably got an open circuit.

The old style heater should produce more than enough heat. The problem in my view is that it chucks it into the footwells when it's your upper body that gets. I've reworked mine to blow out under the dash, so that you can at least warm your hands.

Distributors really are crap compared to 21st century technology. I'm now running an OMEX 600, which is a thoroughly modern bit of kit. Before that I was running a Megajolt, which is very much in keeping with a Seven as it is an open source kit. I've still got all the Megajolt bits if you're interested and it's cheaper than a new distributor.

Fuel gauges work in one of two slightly different ways. You can test a gauge by disconnecting the sensor wire (gauge shows empty) and shorting the sensor wire to chassis (gauge shows full).

I'm not that familiar with the Alpha ECU, but there is no way a coil and distributor will give you the performance of a 3D mapped ignition system. They might give the same peak power, but you can really widen the torque curve with a good ignition map.

I also don't know what you mean about the Alpha being open loop and hence giving fueling issues. People sometimes tweek an ignition map to work round fueling problems, but that should be a last resort, and you never tweek the jetting to get around ignition problems.

I think you are going to find a better tuner.

I got the head from CNC heads, complete with a set of valves, springs and retainers, which I assembled myself.

As for the water outlet, I don't really know enough about bypass water flow (when the thermostat is shut), so I'm just happier with a take off on the head.

I've gone for the ali head myself as I reckoned the premium wasn't so big if you compare final prices (post machining, porting etc). There were a couple of surprises, specifically the lack of water outlet between inlets 2 and 3. I solved this by adding a take off instead of the rear blanking plug as this supposedly gives better temperature distribution between cylinders. I also found that the bolt holes for the thermostat housing weren't quite as deep, so those bolts were bottoming out.

As for steel bits, I went for steel rods from Maxspeedingrods. Of course I will never (hopefully) find out what the rev limit on them is, but they aren't much dearer than Ford's pig iron bits, they look lovely and they save 100g each.

Apart from rods and crank, the cam and followers may want changing to steel.

What sort of power would you be happy with?

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That's how much wire I removed from my old XFlow loom

There are some differences, e.g. different for later fuel injected cars, but at that vintage you are probably pretty safe. The resistance to chassis should be zero when the tank is empty, rising to 180 ohms when full.

I don't know about K series but I did get very good customer service off them when I needed a cam for my XFlow. I think the era of 'magic cam grinds' is over as the science is too well understood, so you just need to make sure you specify cams with the appropriate lift and duration for your application.

For anyone interested in battery technology, there's a decent intro at http://www.edn.com/design/power-management/4458054/Introduction-to-lithium-ion-rechargeable-battery-design 

I cut the plate between the block and bellhousing many years ago so that I can get the sump off in situ. I made a new lower plate from some light gauge ali sheet just to keep the crap out of the clutch and starter ring gear. I'm also still using the original starter motor.

I converted mine in about 2000. The type 9 isn't really as nice as the type 2, and if you don't pick a type 9 with suitable ratios it will definitely disappoint. From memory you need to consider the following:

1. Chassis mods for gearbox mount, Arch did mine because it was with them for some restoration anyway, so I can't comment on the details.

2. I got my type 9 from BGH as they offer one with a long first and a special 0.89:1 fifth. I strongly recommend it as the standard 0.82:1 fifth is useless.

3. Get an alloy bellhousing. The type 9 is heavier than the type 2 and you don't need even more weight to blunt your car.

4. You need a shortened gearstick and a new transmission runnel cover with the gear stick hole further forward.

5. I got the clutch friction plate from Burtons. They were very helpful in advising which one to get.

6. You will need a spacer between the gearbox and the bellhousing.

If you just want longer gearing your alternative is to change the differential ratio. R&R are the 'go to' people, and you can probably afford an LSD for the cost of a gearbox upgrade.

Sorry to hear of your mistake. It shouldn't cost that much to get the liners turned down if you can find someone you trust to do it right. Your pistons will then be too tall but in my experience a bit more compression isn't a problem as long as the pistons don't touch anything.

My narrow band is out in the rain etc. The instructions were that it should not be at the bottom of the pipe (i.e. between 5 o'clock and 7 o'clock) to keep it dry, so it's ended up at about 4 o'clock.

On production cars it is illegal to overfuel them, and the ECU controls fuelling based on the lambda signal to keep the engine at stoichiometric ratio. They can't use extra fuel to cool the sensor, but some manufacturers added extra fuel during the warm up stage which burnt in the exhaust to bring the lambda up to temperature quickly.

I doubt the differences in absorbed power are measurable. A 45 amp alternator producing full output is chucking out 500W (ish, 2/3 of a BHP), which is obviously fixed. The power wasted in the windings, brushes and the like is going to be less than 0.1 BHP, and I doubt that it varies noticeably between bigger or smaller alternators. Disconnecting the alternator at full throttle does have some merit though.

The alternator needs to run lights, wipers, ignition, fuel pump, heated screen, cooling fan and have some juice left to charge the battery. 45A is about the smallest rating I would suggest as adequate for a road car.

I recommend getting hold of a vacuum bleeder. After struggling using all the above suggestions, I borrowed one and got an instant result. My personal theory is that all the pressure systems compress the air bubbles and they stick in the nooks and crannies. Vacuum bleeders drag the air out with the fluid.

Any links to where I can buy an Ali diff nose for an Ital axle?

Don't forget that water is a combustion exhaust product. When an engine is hot, it comes out as water vapour but when the engine and exhaust are cold it will condense out.