Yeah, he got squirrely a time or two. His lines were terrible and inconsistent. It looked to me like he was braking earlier than necessary, but of course I don't know what he had for brakes. I think you could have braked later, though, and been all up his exhaust pipe in the corners, which make have woke him up but also could have scared him into losing control. (An acceptable race strategy but not good for a track night.) With high speed corners like that, you probably don't need to worry about overheating the brakes. Stay on the throttle until you hear harp music or smell brimstone, then stand on the brakes until you can juuuust barely make the corner.
Three or four Porsche badges might make the point... I knew a guy who had a sticker on his mirror that said "Objects in mirror are Porsches."
I'm very glad of that. Machines like this are more than the sum of their parts. That's a good data point. I'm going with the GPS data, which is saying 98 MPH or so. I can't recall what the speedo says at that exactly, something like 120-140 I guess? But it would make sense that the carb issue on the primaries is hurting me on horsepower overall. More reason to dig into this further. The fact that it wouldn't hit 100 MPH seems like it is low. The air filter is the same K&N that was on the car when I got it from you (which means it probably is the same one you raced with). I wasn't kidding about the salad bowl, I still have that on my list of things to do, which could include a new air filter and should increase flow slightly. That's another good idea. Next time I'll bring the floor jack with me to see if I notice that. I know the brakes do get hot, but I've noticed zero fade, including on a 100F+ day. I recall that you also rebuilt the calipers between races, which I've only rebuilt these the one time. I could do some work on the carb and then also try to purposely get the brakes as hot as I can on the street and then perform that similar test. The brakes are probably getting to the point where they could use some more attention. I also think that the Hawk blues in the rear might be too much. I know you ran blacks, but those aren't available anymore - so maybe I should try to find another rear brake pad that's less aggressive. I've managed to get the rear brakes to lock up under certain situations, with capacity left on the fronts. That's the goal! And I'm trying to get to where I have to let off the throttle or use the brakes even less, which comes down to continuing to turn harder. I have more of the track to learn and more personal driving skill to improve on with that. But if you noticed on those first corners after the main front straight, I slowed down (got from 5th to 4th) before entering, and then was in 4th gear basically flat out the whole way through them. I think I can keep moving in that direction. You said more what I was thinking about his driving. My lines aren't perfect, but his were really quite bad. I also definitely could've gotten a lot closer to him in the corners, but that is frowned upon by the officials running the track night (one of the officials outright told me he doesn't personally like running in advanced "Because the *******s in there will get right up on your bumper"). Ok, hint received. I don't want to get a bad reputation. If there were more corner workers, it's possible he might've gotten the blue flag waved at him, but oh well. For me I'm pretty sure it's the brimstone I'll be smelling. And yes, I'm working to head that direction more each time.
Yep, that's exactly why I ran the blacks in the rear. A better solution is a bias adjuster, but less aggressive rear pads can do the job. If the rears have been locking, that might be why you've felt you had excessive oversteer. If they lock up, or are close to it, at turn-in, there's no traction left for a side load (traction circle). Trail braking is a big help to speed once you get it right; you can have 70% of max braking AND 70% of max turn-in simultaneously since the vectors are orthogonal, which means you can carry braking much farther into the corner than you realize. It's all about staying on the perimeter of the traction circle. If you used 3rd gear in those corners, would you have run out of revs before exiting? Ideally, you'd like to use a low enough gear so that you hit your shift point just as you get the car collected from the exit.
BTW, one big difference between street cars and race cars: at the end of the track night, those other guys need to drive their cars home. You just need to have the remaining pieces of the car in close enough proximity to one another to get them onto the trailer. A fully-utilized race car disintegrates as it passes under the night's last checker, so that by turn 1 the driver is sliding on his butt holding the steering wheel and everything else is dust. Whatever is still intact was either over-designed or under-used. (By which you can correctly conclude that I was a failure at getting everything possible out of the car.)
I definitely was doing better at trail braking this past track night vs. previous ones. But I think you're right, since the rears tend to lock first, that's probably part of the issue I'm having. A proportioning valve would be better, especially if I plumbed it so I could adjust in the car. I'll have to do some more thinking on this one. If I used 3rd gear in those corners I'd be above redline going into them. That part is very true, and part of why I like trailering it to the track - no worries about having to drive it home (and frankly it would not be a pleasant drive anyway - as you know, that car is a track weapon and lacks street manners or pleasantries anymore). But I do want it to be usable afterwards. So another interesting data point. One theory I've had about the car is that the old ignition coils might be contributing some, even though I do have spark at all 4 plugs (confirmed as such). There was an Amazon Warehouse deal on an MSD Blaster 2 coil (my favorite high-energy replacement for standard style distributor ignitions). I threw that in the trailing side (no reason, just that was the coil I grabbed). Car immediately started and idled better. No idea what it does beyond that and it still sputtered a bit at revs, I think still being lean, but as you know a lean mixture is harder to ignite and harder on the ignition system. I'm going to keep an eye out for a second coil on a deal (and might even buy one just because), but I think the next job is going through the carb again to hopefully get more cleaning done on it and hopefully find some extra horsepower before the next track night. Plus adding a few pounds of pressure to the rear tires, and likely also messing around some with the brakes, especially if I put on some different rear pads to do the cheap way of bias adjustment, although I might try running an adjustable proportioning valve... I do have the flare tools.
IIRC, there's a short length of hose at the rear between the hardline from the master cylinder and the splitter that goes to the hardlines to each wheel. That hose is the place to plumb in a valve. Just replace it with lengths of hose going to and from a valve in the cockpit. The Wilwood adjuster was the most popular: https://www.summitracing.com/parts/...-XPJD8ngIQgnFKk2gaa2QsdLeqteluiBoCjnYQAvD_BwE . Then you're downshifting too early, or at least letting the clutch out too early. Select your corner gear based on the exit, not the entry. Try it in the leading position. I believe ignition tends to be a bigger issue for the leading plugs than the trailing.
I'm not a race driver, even in pretend, but I will agree that it's more fun to drive a slow car fast than it is a fast car slowly.
In case anyone else is curious whether "proportioning valve" is new age sales talk for pressure limiting valve, it's not. It's a far superior device. No point in me trying to explain it when Wilwood do it very nicely. https://shop.wilwood.com/blogs/news/how-does-a-proportioning-valve-work
If the speedo was accurate with the original 3.92 rear, the 4.88 should give a reading of 122mph when you’re going 98, ignoring tire OD. Not sure if the tire height is the same or not.
Thanks, I wasn't sure what the stock rear was. And yes, that sounds about right, I think 120ish sounds like what I was seeing. I don't pay much attention to the speedo just because I know it's inaccurate and it's the least important gauge in the car while racing. Ok, I think I've now convinced myself to pull the carb apart. Now I need to see if I have enough parts in stock for another rebuild or if I need to order another rebuild kit, I think probably option 2.
First time to comment on this thread to say I've been following it and enjoying, learning quite a bit. Thanks for the vids ...
Glad you've been enjoying it. I need to do some more videos on the car itself, which I've been bad about... I will at some point.
I watched most of your video. That fellow in the Porsche should be in the novice group. Also, too bad for the Fiat driver. I did a track night a few years ago in a rented Mustang (don't tell Budget) and there was a driver there in an older Firebird whose engine seized. I wound up giving him a ride home, it turns out he was a retired racing mechanic, and had lots of interesting stories. It was well worth the extra hour's drive.
I definitely agree. It seemed to me like he had more pride than skill, between being in intermediate and not being willing to point me by. I felt badly for him. However, part of the reason I hadn't started doing these years ago with the E55 Kompressor and then the XKR was that I wasn't convinced those cars would take the abuse well. I was worried about the E55 because it had over 200k miles on it and hadn't gotten a thorough once-over, and I was worried about the XKR because it was a Jaguar. I suppose now I wish I'd gone and done it a bit more, but I was trying to be nice to those cars, and there's no way around the fact that track time is hard on those vehicles, much moreso than simply blasting from 0-exactly-the-speed-limit-not-over now and then.
Oh, and in case it didn't come through, at a couple points I was about yelling "GET OUT OF MY WAY!" at the Porsche.
Ted, I was surprised how far you were from the Boxster's bumper you were in the turns. He should have been sweating that you might run out of brakes and bump him. That does influence drivers with high dollar cars. My son is a driver, and one year he gave me a day at the track for my birthday. It was a BMW club day (He was a member then), and his non BMW car was a relatively slow one, but cornered very well. It had been years since I drove it, so first lap was gentle, and ended with an M3, chip and tires, on my tail, waved him by. I was ever passed again, all day. Always on a BMW bumper by half way around the track, and waved by, regardless of whether they had more speed than I. Coming into the last turn, I would be right on their bumper, second gear, and nursing throttle, so as soon as they signaled, I was coming by. They might have caught me before the hairpin at the end of that straight, but at the next turn, I was clear, and hunting my next bumper. Edited to add: Do you have a horn? Blow it a little longer each lap. The corner workers will flag him for sure. It may not be the approved technique, but it can be done. Top birthday present from him!
I know, I know. For someone who learned to drive in NYC, I was giving him a lot of space. Mostly I was concerned with him losing control and not being able to avoid him.
Managed to find another deal on an MSD coil. So both leading and trailing plugs will have high powered spark, which can only help things. The carb rebuild kit ought to show up sometime next week. I probably won't get to doing anything with it until the following, but the next track night isn't until the 15th, so I've got a bit of time to get that done. I'm debating if I want to do anything with the rear brake pads this time or not. My thought is probably not this round, I want to see if I can't get the engine running better and focus there, and then consider further if I want to do anything brake related on that side. A proportioning valve is really the right thing to do, if I do anything.
An easy change would be to go pick up whatever cheapo rear pads you can get at AutoZone or PepBoys. They're sure to have less effectiveness than those Blues and that might be enough to see if it helps, even though it won't be the ultimate answer. I agree a valve would be best.
