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Wheel Alignment. Wheel Alignment is the mechanics of keeping the steering in proper
adjustment. Correct wheel alignment is essential for easy and efficient
steering and to avoid abnormal tyre wear. All it takes to throw a front end
out of alignment is one bad pothole or one good bang against a curb. Even
without abuse, front wheel alignment will change under normal, everyday
driving conditions. The change may be so gradual that it is not noticed at
first. The first sign of something wrong usually shows up on the front tyres,
which develop peculiar wear patterns that will severely shorten the life of
the tyre. When these appear, the vehicle should have its alignment checked.
Having just replaced the front end bushings and dampers on the
starchief I had a full 3 angle track carried out and must say it’s the best
£50 I’ve spent on the car, it feels like a different car to drive. Front wheel
alignment is determined by the interrelation of three basic steering angles: Camber Inward or outwards
tilt at the top of the wheel. Too much tilt
inward known as negative camber causes premature wear on the inside of the
tyre. Caster Will not affect
tyre wear, but will affect the steering ability and ride of your vehicle. Backward tilt,
know as positive caster, will keep your wheels pointing straight ahead and
when turned will raise the vehicle on one side in either direction, thus the
wheel returns due to the weight of the vehicle after a turn. Too much tilt will
cause the vehicle to bump shimmy (shaking of steering wheel when hitting
bumps) and also give a rough ride. Forward tilt know
as negative caster is not something you want on a vehicle as the steering will
not return and will wander erratically. Too much difference in the caster readings from offside to nearside can cause the steering to pull one way. Tracking Known as toe in or
toe out ( tyres running parallel to each other). Too much toe in or
toe out especially, will wear the front tyres very fast. Too much toe in
will show up as a knife edge on the tyre tread to the inside. Too much toe out
will show up as a knife edge to the outside of the tread. Correct toe in is
critical.
Warning
Signs of bad alignment Are Easy To Spot The warning signs
suggesting the need for alignment are easy to spot. They include:
Fed up searching for the correct spanner / socket when draining the oil? Weld an old socket to the sump plug, all you need is a ratchet from then on. Whilst on the subject of oil, if your automatic transmission has no drain plug you can buy a bolt in kit or if you're tight like me drill the sump and weld a nut inside, use a bonded seal and bolt and presto no more dropping the pan. This was sent in by an anonymous reader, can't see why, I found it informative, it gives a basic idea of tuning carbs and ignition systems.... Ignition TuningOn a mechanically sound car, optimize the ignition timing before playing with the carb. Even if the jets are off, you'll never find the solution until the timing's right. Typical stock-type distributor curves have too much centrifugal advance built into the distributor. Assuming the use of 92-octane unleaded premium pump gas, less than 9:1-compression small block Chevy's like about 10 to 11 degrees total advance in the distributor (20 to 22 as read on the crank), with 16 degrees initial timing at the balancer (for 38 degrees max crankshaft advance). The centrifugal advance curve should start around 1,200 rpm and be all in by 3,500 rpm. A lightweight car with a big solid-lifter cam (more rpm capability) and deep rear gears will tolerate more overall advance that comes in quicker (as early as 2,800 rpm). High compression ratios call for backing down the timing to avoid street-gas-induced detonation. Advancing the timing until the car "pings", then backing it off, doesn't always produce the best horsepower. Try advancing and retarding the timing in 2-degree increments to see if the car speeds up or slows down. Vacuum advance is good for street cars, as it promotes improved part-throttle fuel economy and driveability. Because the vacuum advance doesn't function under wide-open-throttle, you don't lose anything by leaving it hooked up. Hard-Running street cars may benefit from going to a spark plug that's one step colder than stock (but check for evidence of fouling). With high-output electronic ignitions, gaps of around .040 inch are usually a good compromise between getting a strong spark and preserving coil longevity. Carb TuningFirst of all, make sure that you've got the ignition timing set correctly before you start trying to adjust the carb. Before you make any major carb modification, make sure that the basic adjustments are correct. Set the idle mixture screws to give you the highest vacuum reading or the highest idle rpm using either a vacuum gauge or a tachometer. Although it won't affect WOT (Wide Open Throttle) horsepower, a proper accelerator pump shot is important to avoid an off-the-line bog, especially with Holley double pumpers. Fortunately, on a Holley you can play with the pump-cam position, shooter size, and pump cams to achieve optimum response. Non-Holleys may have limited accelerator-pump tuning ability, but at a minimum, they always have a rod you can bend. If your car does have an off-the-line bog, a basic rule-of-thumb is: If the car bogs, and the exhaust is black, the mixture is too rich. If the car bogs and the exhaust is "normal" the mixture is too lean. Jets have a definite affect on WOT power numbers. On a performance application running steep rear end gears where fuel economy is not a factor, jet the primaries and secondaries up or down in equal increments, unless the spark plugs offer a visual indication of uneven fuel distribution. Some carbs use metering rods instead of jets, but the principle is the same. |