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clarkspeed last won the day on September 7

clarkspeed had the most liked content!

About clarkspeed

  • Birthday 04/22/1965

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    Downtown Orlando Florida
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    Building and racing cars. Anything automotive. Guitars. Local music played in local clubs.

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  1. It's a t-nut mounted with a Wilwood adapter plate. They came with screws drilled for safety wire so I assume I will lock them. At that specific interface, it's just screw torqued into t-nut. Hardend steel to hardend steel. But maybe a lot of high frequency vibration also. Your number is exactly the play I have on the rotor. I really just need to verify runout on the hub/hat/plate assembly. I will assume rotor to be true. Just freaked out a little when I bolted it all up and put a runout gauge on it. It rattles with your hand.
  2. Oh it will be a powerful engine no doubt. And should be around 300+ no problem. Just something about tertiary harmonic vibration on the V07 crank that likes to eat bearings. Even with a good damper. If you can sent it to 8k regularly, let me know and I will copy your recipe!
  3. In addition I finally got my rotors in. It only took 7 MONTHS! Dropped them on the radial mounts just to take a look. Still missing the ARP wheel studs to finish out the spacers. Does anyone have experience with floating rotors? They really do float. Both axially and radially. I can see why the bolts require lockwire. So how do I check runout with these? Seems like I need to somehow lock down the float first?
  4. Didn't work very long tonight, but made enough progress to take a picture. CAD design at its best. And fun too! I decided to integrate the radiator shroud into the G-nose for 1 big FG assembled design. It should not need to be removed very often.
  5. I'm no expert at all on this. But I can say what works and add remarks from other engine builders. I don't think knife edging is worth it. I've heard a bull nose rounding is preferred for reduced wet sump drag but have no data to back it up. My builder is doing nothing to my V07 crank. And yes they usually require a little straighten. I also do not have the secret sauce to spin a V07 build beyond 7200 RPM. Lighter weight pistons and rods? I don't know. I don't think super precise balancing is enough. I destroyed one years ago over reving. You can review the TonyD posts, and I have no reason to doubt him. But he doesn't post the recipe either for others to follow. Nor should he. So with that said, the devil is always in the details for a good build. Tolerances, gaps, and clearances must be perfect. And most good builders have their own recipe they don't tell you. My personal experience, and I have built many myself, is pay attention to the details or trust a race engine builder who does. Either way, I do not intend to spin mine very high. As far as bearings, Nismo still sells the "choose your clearance" mix of sizes. I just found that ACR has similar and that is what I ordered for my current build. Maybe I will need to mix a few, maybe not. But with either you have the possibility to control oil cushion to the tenths.
  6. I will dig a little deeper into data collection systems in future posts. After I thought about it, it just seemed like a disservice to jump into higher level stuff without first covering the basics. There is a huge amount of insight than can be gained through a little discipline and basic tools. It is best to exploit these to the fullest before moving up the ladder to more advanced systems. Post #2 – The most basic data you should work with As a continuation of my first post on discipline and making a habit of recording data, I would like to go a little more in depth on what data is important. By far the most important component of a competition car is the tire. It just so happens that it is also the most complicated thing on a car. A tire is composed of fused polymers and chemical additives that once cured exhibit certain characteristics that directly affect the grip and performance of a car. And to make things even more difficult, tire manufacturers cannot predict what the final performance characteristics will be. It is not uncommon for a new race tire compound to be slower than the compound before, deteriorate quicker, require a different set up, etc. And tire manufacturers do occasionally change compounds. If you are at the sharp end of the stick, you will sometimes see manufacturers release new compounds just before the SCCA Runoffs each year. Sometimes everyone switches over, sometimes not. You don’t have to look any farther than today’s modern F1 racing to see how a team’s tire strategy can make or break a weekend. Just a few degrees of ambient temperature change or track moisture can make a tire compound undriveable, and they must race with at least 2 compound changes during a 2 hour race. And by now it should be obvious if you change tire brands you will definitely have something different to deal with when hitting the track. So let me make a couple clear statements which will drive our future priorities on data collection. 1. At amateur levels of competition, the DRIVER has the most influence on competitive lap/sector times. Sometimes up to 70-80%. There is no better way to knock whole seconds out of your lap/sector times than becoming a better driver. 2. Following driver ability, most races are won and lost based on the ability to extract the most out of a tire, as opposed to horsepower. So, getting back to basic data, our top priorities are making sure the tires are happy and somehow measuring the driver. Luckily the first step does not require a large expenditure or knowledge. You are probably already measuring the driver. If involved in competition, you are already comparing yourself to others. As mentioned in my first post, keep a record of where you are at. Here are some examples: 1. Lap times at a circuit and why they were slower or faster than previous run or visit to track. Weather, perceived surface grip, struggles on track are good details here. 2. Your ranking against your peers. Getting better or worse? 3. Get some segment times, have someone with stopwatch measure your time within two key points and other cars at the event. 4. Target another driver who often attends your events 5. Try something different on track and see if the lap times changed for better. Pretty basic stuff but can reveal some trends. Recording this kind of info does 2 things. Forces you into setting goals, and hopefully understanding why sometimes you are faster or slower than other times. Next up it tires. As mentioned, a difficult subject even at the most basic level. So let me make another all-encompassing statement here: Every tire has a happy spot related to temperature, pressure, and camber where it makes the most grip. Again, not a lot of special tools or fancy systems required at the basic level. And depending on how restrictive your class is, this may be as far as you will ever need to go . The first thing I will talk about is pressure. As mentioned, there is an optimum pressure you want to hit. What is that pressure? Without getting into too many details, you will need to find this out for yourself and that can only come with testing. A tire works best when hot, so that is where you when you want to measure the pressure. Tire manufacturers often provide a window but this can be misleading without knowledge of the weight characteristics of your vehicle. And manufacturer provided info will lean on the side of safety, so usually a little higher pressure than required. So to start out take recommendations wherever you can. Online forums, friends, competitors, and the manufacturer info. Then test for yourself. Don’t make small changes at first, for a radial try what you think is a good number then at least 5 psi above and 5 psi below. If you can’t feel anything, try 8psi delta. Record how it feels and which was fastest. Most likely you will find your happy middle number will need to creep up or down. Then over time you can fine tune with lower increments until you are satisfied. And if running a spec class, it is possible that tire pressure is the only thing you have to change handling characteristics. But “hot” pressure can depend on a few factors. Air expands as it heats up, so where you set your cold pressure will be less than the pressure you read as you come off course. With the exception of tire warmers, most everyone will need to predict a cold pressure to start with and measure the pressure as soon as you come off course. So here are the things to consider: 1. Tire air moisture content. The wetter the air, the more expansion. If you use the same air source over and over, this should be consistent. If you would like to limit the amount of expansion, use a compressed air dryer or bottled gas. Air is mostly nitrogen, so switching to pure nitrogen is no better than just using dry air. You can build your own compressed air dryer on the cheap using silica gel desiccant. We have also used scuba air. 2. Ambient temperature has to be adjusted for. Setting your cold pressures on a 40 degree day will be lower than on a 80 degree day. If you normally allow for 5psi of pressure rise, you may need to allow for a 10psi rise. Be careful here, the fastest way to heat a tire is pushing high slip angles, but if it is really cold you may need to bring up the temp slowly before attacking a corner. 3. Use a reliable pressure gauge that is calibrated. 0.1-0.2 psi resolution. Don’t be afraid to check it against other gauges over time. Never use a friends gauge to set your pressures unless you can verify it reads the same. Repeating the same pressures you like every time is important. 4. Your goal should be predicting the hot pressure +/- 1 psi or better. 5. And as a side note, swaying back and forth to warm the tires before a race has limited impact. You can also use the brakes to create slip angles and put heat in the tires with the added benefit of getting some residual heat through the rotors and wheels. Often this is more beneficial. Next to consider is overall tire temperature. A tire pyrometer works best but a cheap IR gun also works in a pinch. Believe it or not, this is the simplest thing but many have problems here. Most pure race tires operate in a range from 170 to 210 degrees F. I don’t know what the current crop of 100 and 200 TR tires operate at. So if you are running an R compound or slick, and you measure 130, you are not in the range of most grip. There can be many reasons for this, the least of which is not driving hard enough. Too stiff a spring rate and excess shock valving can also show up here. Along with a damp cold track. If you can’t get enough heat in your tires most other testing is useless. Remember to take good notes. Tires that are too hot can also cause handing problems and deteriorate quickly. Next up is temperature across the tread. This is where you can really pick up some grip if driving a stock based car. Street vehicles have only a small amount of positive camber allowed within their nominal alignment settings. When a car corners aggressively, the body lean overcomes this angle and most of the weight transfer ends up on the outside edge of the tire. The tire contact patch area becomes very small. Continue and you can cord the outside edge very quickly when track driving. I am not going to go dive very deep here, most race rules allow for some kind of camber adjustment to compensate for this. Even restrictive spec class rules allow you to loosen every thing up and maximize the bolt hole runouts. Better than nothing. Anyway the idea is to have the tire tread as flat as it can be during maximum cornering. This usually requires some positive caster, especially on strut based suspensions. One of the best ways to measure this is by taking tire temperatures when exiting the track. You are looking for even temperatures across the tread measured on outside, middle, and inside. It is generally accepted 10-20 degree more on the outside measurement compared to the other 2 is about right to maximize the contact patch. Some considerations for temp measurement: 1. Take temperatures as soon as you can when safely exiting the track from a hot lap all the way up to the last turn. The tires will cool down very quickly on a cool down lap or a long straight before the pits. Best is to test on a skid pad. 2. Take temps the same way every time and measure pressures following. A recording tire pyrometer works wonders here. 3. Record everything. Adjust camber accordingly. Don’t forget to set toe also following a front camber adjustment. 4. LOOK AT THE TIRES! I mean really look close at how they are wearing. Make notes, take pictures. Look for evidence of over driving, bad camber, flat spots, wear rings, excess or inadequate pressure. Other data to think about includes various temps and gauge readouts. Ever look at an oil pressure gauge and wonder if it 5psi lower than it should be? It’s a good idea to make a note of what your various gauges read nominally. Maybe even put a little piece of tape on the glass as an indicator. Just knowing there is oil pressure is not enough. Better to know immediately if there is a couple psi drop or a few degrees increase in temp. IR guns are good for this also. Cylinder head temps, transmission temps, differential temps are all good things to record and refer back to if needed. Enough for now.
  7. Umm the red eye. Believe it or not, depending on which road you take, I am on the way to Daytona. My shop is maybe 3 miles off the 417 Toll Road in Oviedo. My weekend is fairly open except for plans Saturday night. When are you driving back?
  8. Finally, finally, finally, got the front panels locked in with gaps I think are "acceptable". This was pure hell tack welding in the 1/4 turn fasteners where they exactly need to be, then cutting them and rewelding 3 or 4 times, in between fitting the panels 5 or 6 times for each weld. 5 panels fixed, 2 fenders, g-nose, hood, and cowl panel in relation to 2 doors and window frame. Think 3 dimensional chess with 3 players and 3 boards. No way to predict what will happen when you move something 1/8 inch. Maybe 20 hours of this AFTER I thought I already had the fenders in correct place. And this is by no means close enough for a show car. Panel gaps and heights of panels are still all over the place. I'm only shooting for a good aero properties and looking good from 25ft away. But reshaping the FG panels is off limits for this build. I do not have enough time and will not make me any faster. But I still think I may try to alter the hood shape to match the g-nose. I will claim another milestone complete. Next is integrating the customer radiator shroud into the g-nose.
  9. What is your schedule for the Daytona race? I was planning to go for the day Friday but too many other things to do. Would like to meet you. My shop is about 50min away from track.
  10. This is what I plan to cover in more detail. #1 tire pressure, temp overall, temp across. IR temps of various components. And gauge read outs. Continuation of my last post and JHM post. Video. No data ack system required. #2 Data you need vs. Data you want. Autox, hill climb, rally stages, hot lapping, racing, sim racing, testing. Intro to electronic data ack. How much should you spend? #3 Basic systems. Basic info. What to look for. Car vs driver. Comparisons with self and others. Trends. Consistency. Money trace (speed vs. Distance) G circle. Keeping it simple so everyone can use and understand basic info from any system. #4 Advanced, math channels explanation, braking, kpi's for track, car, and driver. Shock tuning, combined with other chassis analysis. Not too deep here, but awareness of possibilities. My posts will be very generic. No references to manufacturers or systems to get the data. I will rely on the community to fill in the blanks for the best or optimum or cheapest way to get there. I am no expert on everything out there. I have played with AIM, MOTEC, and Race Technology analysis software which are all similar. And I have been studying basic analysis recomendations for the last year which kind of gave me a appreciation for the basics, and triggered me to start this thread. With the exception of post #4, most all data is available from phones, AIM solo, Garmin, or similar inexpensive systems. You guys fill in the rest, which you already are!
  11. Thanks all for adding to discussion! Very good comments on phone based systems of which I have not played with for 7-8 years. I have been putting off my 2nd installment in this series, but now motivated to type it up. It will be the next step beyond my 1st post. In the meantime, I have an older Race Technology DL1 currently for sale on Ebay at $100 if anyone is interested in moving up to something VERY powerful. I tested it and it works great. Contact me and I will be happy to answer questions about it. For a Hybrid buyer, I will even put some analysis setups in with it. Eventually I intend to make a number of posts with very good primer on progression into data systems.. what you need at what level you are. Just need to get all this work travel behind me.
  12. Never had a problem with grooves, but I still prefer disks with spring combined with HD pressure plate and lightweight Flywheel for street apps and racing "on the cheap". Feels so much better and can handle anything a NA L6 puts out.
  13. I have found the toughest thing on a 5.5 and smaller button clutch is pulling it on a trailer. Many winch just for that reason. I also found the 7.25" dual clutch set up to be much more forgiving. Virtually same durability and heat resistant as a stock based setup. Can work for street or track.
  14. Still slow progress. Hurt my back and lost the weekend. Getting really close to having the gnose and fenders fixed. At least I finally have the steering column in. And then found 2 interference points. At least I feel like the week was progress. Slowly chugging along.
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