johnc
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Posts posted by johnc
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Don't use brake cleaner on anything that will be heated or welded. Acetone is safer and cheaper then brake cleaner. You have to physically and chemically remove the POR15 from any surface you intend to weld.
We get old Porsches in the shop that have POR15'd floor pans and suspension pans and its cheaper for the customer if we cut out and replace the entire POR15'd paneland replace it with a new then to chip, wire wheel, scrape, and clean the areas to be repaired.
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There are two separate but related issues - clamping force and hydraulics. When calculating the hydraulics you you need to count the surface area of all the pistons (caliper and MC) in the system. For clamping force you just need the hydraulic pressure number and the surface area of the pad.
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I've seen it happen and "always" is never true in road racing. The winner of the race is the one that crosses the finish line first, not the one with the most horsepower. My 325hp 240Z beat every Viper, every Z06 Corvette, every Mitsubishi Evo, every Porsche 911 at the 2003 and 2004 OTC.
Compare lap records at various race tracks and you'll see that many low horsepower cars can lap at equal or better times then higher horsepower cars. When I raced Spec Racer Fords we had all of 110hp yet our lap times at WSIR (arguably a horsepower track) were equal to race cars having double or triple the horsepower we had. A Formula Atlantic with 240hp will absolutely destroy ANY Corvette or GTR on any road race track in the country.
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You can sell these as a vendor. Just create a thread in the Vendor Forum, but be aware that we hold vendors to a higher customer service standard then regular folks selling stuff.
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Hope he gets that price. Doubtful, but there's always a change. Probably sell for about $35K.
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And power levels do matter for brake systems in pretty much any form of racing, a 120hp car can only make it to 80mph before needing to brake to enter turn A where a car with 300hp can make it to 110mph before needing to brake to enter the same turn which puts more load on the brakes and tires causing them to fade and overheat.
Its not the horsepower, its the vehicle weight and speed at the end of the straight plus mid corner speed that matters as far as braking is concerned. Its common on a road race track for a lower horsepower car to have a higher speed at the end of the straight and the end of the braking zone due to much better handling and lighter weight.
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That must have been Joe Izusu.
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New R&Ps for the R200 have been NLA for at least 5 years.
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Focus on brake balance, not piston quantity or size. Good brake balance is the most important aspect of a brake setup.
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Jim is no longer with Kinetic. I know of two people waiting for engines and they have been waiting a long time. Jim is currently managing one of GMG Racing's engine and development programs. http://www.gmgracing.com/
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Are you building a handling car or a style car?
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A wider track reduces lateral load transfer. In general its a good thing and in a front engine/rear wheel drive car you run a wider front track then rear. This lets you move roll stiffness forward and lets you soften the rear for better corner exit acceleration, but it can increase front understeer. A wider track in front has a negative affect on turn-in (slower) and can give more positive scrub radius depending on how the wider track is achieved. This makes the car more nervous under braking and give a less sensitive feel. A wider track in rear (on a front engine,RWD car) increases oversteer and makes putting power down in a corner more difficult.
Reasons not to do this are: 1) Body interference, 2) if you don't get the steering geometry right the car will feel dead in the steering wheel and nervous under braking, 3) increases in under or oversteer depending on which end of the car has the wider track...
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The color doesn't matter. Just bleed a 1/4 pint out of each corner and you know you've flushed most of the old stuff out.
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$3,200 is a good price even without the group buy. I had more then that in my LD28 crank after knife edging, nitriding, etc...
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They were pretty damn funny and generally gave useful advice.
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I have to be really careful when manually bleeding with a clear tube that always ties to pop off, and I still make a little mess.
Buy the correct size clear plastic tube.
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when i press the pedal it is full soft and brake light goes on.
The brake pressure switch is tripped and needs to be reset. You have to thoroughly gravity bleed the brakes and get fluid to all four corners before pushing on the brake pedal. If you don't, the difference in brake pressure front to rear causes the switch to trip and block off brake fluid flow to either the front or rear depending on which end has the lowest pressure (most likely the rear).
FYI... throw away the speed bleeders. The exacerbate the problem you're having. You have to get the front and rear hydraulics full of fluid without touching the brake pedal and speedbleeders keep that from happening.
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It's not an oscillation so damping won't work. You can reduce the effect by running camber angles less then 1.5 negative, add toe in, and add caster.
A little rear toe in also helps.
And not fighting it with steering wheel helps a bunch. Relax your hands and shoulders and let the car move a little.
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Tomato, tomaahto. I cleaned up the misunderstanding.
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The shape of the tire footprint affects directional stability. A long, narrow footprint is more directionally stable then a short, wide foot print.
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When you were running this size wheel you didnt run into this issue with your TT 240 car?
No issues on the ITS 240Z with 14" wheels, but we couldn't run the steering arm spacers. On my track 240Z with 15" wheels I did have a slight problem but I cut the spacers down about .083" and fixed it. Not an issue when I ran 16" wheels.
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You're fine if you drive easy on the street to the alignment shop. You should replace the prop valve ASAP after that and properly set it. One rainy day and a panic stop could destroy your car and yourself.
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From Tire Rack:
What's the downside to negative camber? Negative camber leans both tires on the axle towards the center of the vehicle. Each tire develops an equal and offsetting "camber thrust" force (the same principle that causes a motorcycle to turn when it leans) even when the vehicle is driven straight ahead. If the vehicle encounters a bump that only causes one tire to lose some of its grip, the other tire's negative camber will push the vehicle in the direction of the tire that lost grip. The vehicle may feel more "nervous" and become more susceptible to tramlining. Excessive camber will also reduce the available straight-line grip required for rapid acceleration and hard stops. -
Your car has a road race/autocross alignment which is designed for quicker turn in response (among other things). Its supposed to do that.
Pilot Bearing v Pilot Bushing
in Miscellaneous Tech
Posted
The roller bearing style offers no performance advantage unless you're consistently shifting above 7,000 rpm. Even then, its probably not significant.