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Ron Stygar Carl Buckland Dale Beuning Forums Help
From digest.v5.n36 Sat Jul 27 04:46:16 1996 This is from a buddy who drives an RX-7TT who posted it to the RX-7 list in response to a "I'm going to my first track event: what should I do to get ready." He thought I might find it interesting enough to post, and sure enough I did. (I left the turbo stuff in for you Dinan (or whatever) turbo fiends.) He is a local hotshoe in SCCA SuperStock (SS). At the next autox we're going to trade cars: he'll try PeeKay and I'll try the RX-7. Should be interesting! (Note: the alignment and pad changing details are specific to RX-7s) >>Subject: <3rd/Gen> Track Prep Advice? Make sure you check the brakes well - you don't want any piston sticking, etc. I personally prefer Motul Synthetic (Dot3, totally miscible with other Dot3 fluids), and Ford Heavy Duty (also Dot3) seems to be the other popular fluid among track types, at least in the NorthWest. Worthwhile to get into the habit of always changing brake fluid before a track event - brakes are the one thing you don't want to mess with. Make sure you have at least 2/3 of your pads left, and bringing a spare set wouldn't hurt, especially fronts. The car doesn't get adequate front brake cooling (see my previous post re the cooling kit I'm looking to get), and esp with stock pads it'll go through them quickly, esp. if you're aggressive with the brakes. Might want to switch to Porterfield R4S (their street/race compromise pad) or Hawk Blues or something like that. The stock pads will partially vaporize and leave a film of crud on the rotor if they get very hot, requiring the rotors to get turned, plus it reduces friction so you won't stop as well. If you get into ABS at speed, it also tends to 'chunk' (crack and/or break pieces off the edges) the stock pads because of the rapid pulsing and high loads. A week should be plenty of time to get pads ordered if you can't get them by Monday, so you might just want to have the shop turn the rotors and change the pads yourself when they show up, then have your current set as spares. You should be able to do all four yourself in under an hour
A jack, tire wrench, a set of open ends and a big screwdriver or C clamp (to push pistons back) are all you need to change front pads at the track. If your pistons seem stuck and won't go back in easily, and your pads are warn all the way or almost all the way down, they've likely jumped partially out of the cylinder. This has happened to me a couple of times at the track. I put a smaller screwdriver inside the piston (it's partially hollow) and gently pry trying all directions. It should slip back in at one point, and then be easy to press back into the cylinders. Get a decent alignment done - for the track I like 1/16 out in the front (though you might want to start with zero your first track day - the front's a little twitchy at 1/16 out, and turn-in isn't as critical as for autocrossing), 1.2 degrees negative camber all around, as much front caster as you can get, and 1/16 toe in at the rear. Todd Serota seems to prefer zero rear toe, but I find zero makes it too easy to get the back end out under trail braking into a corner, and makes the car wander under severe straight line braking when the back gets highly unweighted. For your tires, I'm not sure what part of the country you're from or what the track surface will be like - fresh RSII's might be a little soft for track work on an abrasive track and/or if it's very hot, so you might not get that many track days out of them, but they should be a lot of fun! I run my RSII's (same size) at 30 psi warm, 29psi totally cold for autocrossing, but run BFG R1's at the track. The RSII's heat up a lot quicker (and more) than RS's, so you might actually want to try a pound or two or three less for the track. I never measure hot because it affects the pressure so much it's tough to get accurate readings (could be anywhere from 2 to 6 psi higher). Bring oil - under boost the car goes through oil like mad (it's designed to vastly increase the metering when the 2nd injectors are on), and it's not uncommon to go through a quart and a half on a track day. It wouldn't hurt to change the oil and filter if you haven't recently and are even getting close to the change interval. I always change the drain plug gasket when I change oil, although many people would call that a little paranoid - you do not want to be losing any oil on the track, for the sake of other cars at least as much as yours. I also bring a garden sprayer full of ice water. I fill it partially full, lay it on its side in the freezer, and freeze it overnight, then fill with cold water and ice cubes in the morning so that it stays cold all day. I use it to spray down the oil coolers (only 1 if yours isn't an R1/R2) after runs until they stops steaming and actually drip onto the ground. Keep the engine running so the oil flows through the cooler, and let the engine run with the hood up for at least 10 minutes, otherwise you'll boil your coolant and quite possibly coke your turbo bearings from heat soak. Hold your hand above the turbos just to the right (looking back from the front) of the ABS unit after coming in from the track and you'll be amazed at the amount of heat being released. Take good advantage of the cooldown lap and don't be tempted to use it to get just a little more hard driving in. Try to keep the turbo off boost (to minimize heat generation), and use the brakes as little as possible (again to let them cool as much as possible), but try to run reasonably high speeds (>60mph) to maximize airflow through the brakes, rad, and oil coolers. When stopped, try to park somewhere level so you don't have to use the handbrake - you don't want any pressure on your pads or they can stick to the hot rotors. Bring some duct tape as well - I've used it to temporarily repair both a split intercooler hose and a popped off boost sensor hose. And have fun!<<
John Browne |
