'Such a technical track'

[gordon0412]

Getting excited about next weeks advanced PDX. Somewhat surprised, pleasantly so, by some of the people I see signed up for it. I and a buddy went out to the HPR gala a couple of weeks ago. We went out to the fence facing 13-15 to watch the celebrity race. As we were waiting I felt something wet brush my leg. It was Apex's nose, and of course on the other end of the leash was Andrew Jordan who'll be doing the PDX with us. We started talking and one of the things he said was he loved HPR because it's "such a technical track". I think I know what he means, but am not certain. Anyone care to elaborate, and help educate me?

[LoCore]

A "technical track" to me is one that is difficult to master. HPR I think is going to be one of those tracks that is easy to pick up--we'll have you driving the line after your first session--but will take many, many sessions to drive effectively every lap.

Another technical attribute in my view is how connected the corners are. HPR really isn't a learn one corner at a time track, as each corner, each decision, impacts how fast you will be through the next 1-3 corners!

This season has been a lot of fun learning HPR and beginning to crack the puzzle.

Another part of the technicality is that there isn't just one way to drive it. The "right" line is car and situation dependent.

While some were worried that the reduction in track width from 40' to 36' would make the track feel "tight", the corners feel absolutely huge in most spots. For the road racers, that leads to the possibility of passing on most all corners of the track. For us "time" guys, it means that there are multiple ways to drive each corner, and its damn difficult to figure out what is going to be fastest.

In general, data is suggesting that shortest distance continues to be the best choice time-wise, especially in the really long corners (T7 and T11 in particular). However, there are some slow corners (T6, 8, 13) where getting the "right" speed is proving damn difficult--data is showing that 1-2 mph too *fast* costs up to 5-6mph at the next track entrance!

Bottom line: you're going to have a blast at the Advanced PDX, will be able to drive the track confidently and safely (and not get lost :-) ) by the end of the day. But you'll have things to work on for many, many sessions.

[LoCore]

Surely someone else has an opinion...

This is such a shy group :D

[shoeish]

Trade offs in your line between corner radius, camber, entrance speed, exit speed.

You will also need a technician to replace front left tires. :D

Dave, where is the "too fast costs you speed" section?

http://www.shoeish.com/uploader/images/m3.jpg

[LoCore]

The location where too much speed costs you the most time?

Why it is exactly in the picture that you posted. Data is showing a speed different of 1-2 mph too *fast* in T13 entry costs me 5-6 mph all the way down the pit straight.

[blamkin]

I'm certainly not the fast guy out there, but let me see if I can crack the puzzle a little as Dave says.

The first thing to know about HPR is that road camber greatly affects several key turns. If you don't understand this, and just drive the line "as presented" by the tarmac, you will be either too slow, too fast, or simply in the wrong place.

Turn 3: Just looking at the entrance to this turn, there's a visual illusion that it's pretty tight. The reality is that the exit is far larger than the entrance... meaning you can simply go faster than it looks like you can... (which is good since this might be the most important turn on the track - leading on to the straight). Two right-side wheels on the concrete burm is an absolute must, as is setting up as far to the left as you possibly can.

Turn 5: taking a middle apex lands you in a sweet "bowl" that is correctly cambered. Get set up and on the gas early, and the bowl will add stick. Get it wrong and you will either incorrectly think the turn is slow, or you'll fly off the track going down to 6. Setting up for this one pays of huge - especially difficult because of the speeds through 4.

Turn 10: Most cars need to brake, going downhill, into this one - that itself is hard enough to get right - however the exit of 10 cambers up nicely and adds grip. So, once again, you can go faster than it looks - but warning here - going off is "Bad" and has severe consequences. One car already totalled "down there" and I somehow managed to keep mine together, even though I was so far off the track I couldn't see it any more.

Turn 13: This turn is cambered - but for a different track configuration, the short course! If you look at that pic, the turn is cambered correctly for coming from the other course - meaning that it's cambered exactly wrong for the direction you're driving. There is a one-lane "flat" section, right near the burm, that sticks OK... but if you get off it, you're completely screwed. Make certain you're already accellerating when you get to the concrete burm there - and for that matter put the left side tires on it to be safe.

Hope that helps someone.

[Built-By-Bones]

great summary Bill

I'd add that 6 and 11 offer a variety of lines, my current belief (subject to change) is the auto-x line works for low HP cars, like the Mini. Shortest distance. Screaming around the outside seems fast, but can add over 250 feet to a lap distance :eek: :eek:

[gordon0412]

Thanks guys, good stuff. Bill I realized that about turn 3, but the rest of it was educational for sure. Course I'll probably be hearing more about it Saturday.

[BlueVelocity]

Dave, where is the "too fast costs you speed" section?

http://www.shoeish.com/uploader/images/m3.jpg


In that corner you have in the pic! LOL:D

[gordon0412]

Speaking of different lines and distances. I noticed doing segment analysis with Traqmate that the distances traveled through one segment by two different laps would be different. I assume that comes from taking a tighter or wider line? If there is one thing I think I've learned it's that for even high HP cars taking a tighter line is often faster than carrying more speed through a wider line.

[LoCore]

Speaking of different lines and distances. I noticed doing segment analysis with Traqmate that the distances traveled through one segment by two different laps would be different. I assume that comes from taking a tighter or wider line? If there is one thing I think I've learned it's that for even high HP cars taking a tighter line is often faster than carrying more speed through a wider line.

The accuracy available to Traqmate is several feet. Also, laps taken at different times of day results in "satellite drift" which will move the entire track on the Traqmate output. Use Traqview to line things up.

In other words, not surprising to find a few feet difference each lap. 50+ feet though, and you're measuring real differences.

[shoeish]

In that corner you have in the pic! LOL:D

HA! No kidding in that corner. My line vs. Dave's line put him about 200' ahead and pulling on me through the pit straight.

I stole Dave's line through T14 (as well as a few other places) and went from just touching the rev limiter in 3rd gear before braking for T1 to being well in to 4th gear.

Thanks for the lines, Dave. :)

[LoCore]

Thanks for the lines, Dave. :)

No problem--that's my job. :-)