altezzaclub

I don't think they have found a reducton in traction from narrower tyres as they rely on the larger circumferential footprint from a larger tyre So we're working on a similar footprint area but the tyre diameter is larger for a fixed rim size. So new diff ratio needed. I don't think many people suffer from lack of traction normally, but I suppose when its an emergency braking situation it becomes important! What didn't get mentioned was the change in handling from the taller sidewalls flexing, one of the big selling points for low sidewall ratios. The other side of that being a better ride from the tall sidewalls as they soak up the potholes, and tall tyres do more Km than tyres with small sidewalls. Tall tyres soaking up potholes also means far fewer bent rims too. As an aside, I see some tyre pressures are going up with people talking about running 38psi now. That won't help the ride quality!

http://www.drive.com.au/motor-news/skinny-tyres-the-new-fashion-20141004-10qelg.html?utm_source=outbrain&utm_medium=cpc&utm_campaign=outbrain_amplify Tyre design is blasting back to the future with car makers set to adopt larger diameter wheels with significantly skinnier tyres than most cars are running today. Despite decades of tyres getting bigger and wider, there is a new trend towards narrower tyres with a large diameter. The emerging trend towards skinnier tyres is being driven by a desire to reduce fuel use and carbon dioxide emissions. Tyre companies, including Michelin (pictured) are experimenting with taller, narrower rubber. "This is the new future," said Damien Hallez, Michelin's head of technical communications. "It helps to improve the energy efficiency [and use less fuel]." Hallez said every centimetre a tyre increases in diameter there is roughly a 1 per cent reduction in rolling resistance (all things being equal), which is the tyres internal resistance that slows it as it rolls across the ground. So increasing a tyre's diameter by 2 inches (tyre diameters are measured in inches, not centimetres) would reduce that rolling friction by about 5 per cent. Having less rubber width also brings improves aerodynamics and further reduces rolling resistance. "Increasing the diameter we gain in rolling resistance without losing all the security aspects of wet and dry grip," said Hallez. "There's less deformation of the tyre in the compact patch [the part of the tyre that is touching the road at any time] and less deformation in the side walls so that helps to gain in energy efficiency." He also said skinnier tyres were better suited to dissipating water, therefore reducing the chance of aquaplaning, or skipping across the surface of the water. "It's like a boat, it's much more efficient [at going through water]." Renault design boss Laurens van den Acker agreed wheel and tyre designs would continue to get larger in diameter but with skinnier, more energy efficient tyres. "It is one of those things that is the best of both worlds," said van den Acker. "The designers want big wheel and the engineers and aerodynamicists want narrow wheels. "It gives you good comfort, it's good for CO2 … because it has less resistance." Van den Acker said the only potential negative was in braking performance, something that had to be monitored. But he said the benefits far outweighed the negatives, particularly when it came to aesthetics. "If the choice was between having large tyres that are a bit skinny or small tyres that are a bit fat I would still go for the large ones because from the side view it is undoubtedly better," he said. However, because the skinny tyres are still relatively new – despite being similar widths to tyres sold 40 or 50 years ago – van den Acker said there were issues with supply of replacements. "What's stopping us is not technology, what's stopping us is tyre manufacturers who are just happy to supply the same tyre and the clients who are feeling more comfortable that the tyre can be bought anywhere, so you have to create a market for these special tyres," said van den Acker. BMW is one of the first manufacturers to use the new breed of skinny tyres in a production car with its upcoming i3 electric car. The bulbous carbon-fibre-bodied hatchback gets wheels that are 19 inches in diameter – commensurate to the diameter of wheels used on many performance and luxury cars – but the tyres are almost half as wide as some tyres. At the front the BMW i3's tyres are just 155mm wide, while the rears are 175mm wide. By comparison the popular BMW 3-Series has tyres that are between 225mm and 255mm wide, while the Holden Commodore tyres range from 225mm and 275mm. Various concept cars have also used the larger diameter skinny tyres, while Citroen's C4 Cactus uses 18-inch tyres that are just 155mm wide. Michelin's Hallez said in many cases the contact patch of rubber on the road was similar to a smaller diameter, wider tyre, so grip levels were often not compromised.

hmmm.. I'd have to measure one day, but the RA40 runs larger struts than the KE70, and the Bilstein people in Sydney machined those struts out to a larger diam again to take the Bilsteins we run. As it is, they fit on the KE70 with Celica steering arms and LCAs. (same as RT Corona LCAs) Is it worth worrying about the AE86 struts Luke? Can you find something else from the Toyota lineup to do the job?

I did some stuff that actually made a difference..

Blzbub is likely right if you have had new tyres balanced and a wheel alignment done. Either you had a buckled rim on the back and they fitted it to the front with the new tyres, or maybe a wheel weight fell off, which is a polite excuse for some guy who did a lousy balance job. Hold a screwdriver on a solid object like a concrete block beside a jacked-up wheel and rotate the rim past the screwdriver. Watch to see if the rim moves closer and further away. Do inside and outside of each front wheel. If you find one that is 5mm or more out swap it to the back. If they both check out OK go back to the wheel balance people and ask them to check both wheels. While you have each wheels jacked up try to wobble them vertically (wheel bearings) and horizontally (steering knuckles) as Banjo said. Any play will need investigating. The more you do yourself, the less you have to pay someone else to do.

Yeah, those compressions aren't that brilliant, just run it for a year and see if they get worse. Sort out everything else and then investigate if its rings or valves, & by then you will have a better idea about everything.

Surely that's all they have? The carbs themselves are crap, the 'twin' aspect is cute but in the end they are downdraughts and not sideies, and a single DCOE will blitz them in a modded motor as you can buy a wide range of jets and chokes. ..or are you saying I should go and get that pair that are sitting in the wreckers every time I walked past for the last few years because no-one wanted them ...

..and an alignment when you get the balance done. Did you get either done when you lowered it and fitted the new tyres?

Sooo.... new radiator setup then? What about oil surge too? is that a problem? It certainly solves the lack of torque in a 4K !!

What Parrot said! Make it comfortable to drive, not a hard noisy rough race car if you're doing 100km a day. See what you can do for good shocks to go with the new bushes and if there are ways of getting a tad of extra camber on the front. Toyo T1-R or whatever they do these days, I think they might be R1-R now, or Falken FK452 or something really grippy would make driving it more enjoyable. I always run my tyres in pairs so I can pick different front end handling to rear end. Chase down thicker sway bars and see if the guys that bought them reckon they are value for money. I don't know what you can do to the 4AGE, they were pretty good straight out of the factory and you don't need it with hot cams and lousy low-down pulling.

Damm that is clever! All those 4AGE conversions where you have the dizzy on the back of the motor, poking into the firewall... You've just solved all those problems! I'm running two narrow-band oxy sensors, one in #1 and one in #3 for reading each of the twin carbs. I have a switch on the display to flick from one to the other and make sure they are the same.

Obviously something from a car with over 300rwkw as stock. Walkinshaw or FPV can fix you up, but anything 4WD is too weak as they split the torque and Skylines don't make 900KW reliably. Lexus, Bugatti, Lamborghini, just check out your local wrecker...

1)-The pointy end of the screwdriver is the lever, the fat end is where the hammer works. 2)-If you're under the car and your boot can't loosen the nut when you kick the spanner, the hammer will do it. 3)-The hammer is always the answer... Volunteer to help a mechanic in your spare time. You'll be a pain in the ass for the guy, but just ask loudly at the pub is anyone is a mechanic and ply him with beers until he agrees...

I supplied a pair to Murray Cootes Suspension (the famous MCA of motorsport) and all they wanted was the casting with about 100mm of tube on it. They weld a new tube onto that bit I suppose, so I assume you don't get them out of the casting very easily at all. You could give them a call and just ask. If you look under the strut isn't there a massive weld all the way around the inside of the cup? Is the tube closed at the bottom, pressed into the casting and welded underneath?

Apart from 'low' are there other factors you want to look at, like LCAs or sway bars? I don't run mine low, just a coil chopped off the stock springs in the front and a coil & a half in the rear, but more camber at the front and more stiffness in the rear made the handling far better. I still have space between the top of the tyre and the guard.

I put my pair about chassis rail level, before the collector. getting them to fit was 'interesting'.. Even though they are heated it takes a minute of driving before they settle down and give consistant readings, they seem to need a warm-up period and need to be hot to work.

A nice rebuild, you must have done a lot of work there. We can have a Netherlands sub-section soon!

That looks a whole lot more fun than pouring it on the ground and setting fire to it!

That's a typo for 'float level', in case anyone is confused... Second of the dodgy fixes is to swap the two middle plug leads and crank it over. The massive backfires coming up the carby blow stuff backwards out of the jets... apparently!

Haha! best outcome you could have!

Well, certainly a tuneup would be the first thing. Check the plug gaps and make sure all plugs look the same. I expect it no longer has points, so just check the timing and the resistance of the leads. Check for any inlet leaks from loose bolts, broken gaskets, split rubber hoses.. Then find a carb kit for sale for that motor. You may not need it, or it may be hard to get, but at least you know where to find one. Pull the carby apart & take a look inside. If there is dirt in the bowl continue pulling it down and clean it all. I squirt it through with petrol.from a syringe. If the gaskets look dodgy then fit the carb kit. If its all clean, change the fuel filter. (where all the dirt is..) Finally run it to fully warm and set the idle mixture screw. Furthest inwards you can get for the fastest, smoothest idle.

cooked... Check for blown headgasket before chasing anything else. Do a leakdown test with a compressor because if it was leaking compression into the water system you would be losing the top tank of the rad every day. So I assume it is leaking compression between cylinders. You could first try the "start with full rad and no rad cap" and look for bubbles and overflow of water, but I don't't know if that works on a 4AGE, I haven't worked on one yet. If you get compression bubbles coming up through the radiator while the engine is cold (thermostat shut) then it is definatley head gasket goneski. If you don't get bubbles, then do the leakdown test. If it holds compression in every cylinder, change the coil/condensor whatever it is using as that would give the same symptoms of running fine on no-load but breaking down under load. Less likely I'd say as it would give a direct misfire rather that fire back up the inlet. Running lean also gives free-revving OK but spits and coughs under load. Nornally I'd look for a blocked jet in the carb, but I assume you can't have that problem...

"I want that crossmember black Soldier, and I want it black NOW!" lookin' good- massive rebuild!

Which motor?? The pathetic 21R, the pathetic 2S or the almost-just-as-pathetic injected 22R?? ..and just what does 'quite jumpy'mean?? Misfires? Surges? It sounds like a blocked jet in a carb, but our Pulsar SSS with its injected SR20 stalls on my wife a lot.

Go buy a $10 multimeter from Supercrap. The white wire going into the ignition lock is carrying power into there, if the ignition lights work then the power gets that far and the "ignition" (not 'start') part of the key is working. The black/white wire to the solenoid should be live, so unplug it off the starter motor and test that. You'll need to have someone holding the key on 'Start'. If power is getting to the solenoid but the starter isn't working, pull the starter out and test it on the bench. If power is not getting down that black wire then your suspicion is correct and the key lock is not connecting internally. It pulls apart easily enough to inspect the contacts. If you are unfortunate enough to suffer an auto, there is a shift lock switch in there too, making sure you can't start it in drive. That might be faulty.