Quote from AndroidXP :

I can confidently say that this is still an issue of car/track knowledge and not yet being accustomed to LFS. Setup changes could help you get faster if they eliminate a certain trait that absolutely kills your speed, but generally speaking you're still too far away from a laptime where setup analysis would yield usable results. For example, I just tried my first ever two laps on SO4/UFR with the default hard track setup, and I managed a 1:44 on my first flying lap - driving one handed with the G25 wheel to the left of my keyboard, that is

It just takes some time till you learn to "think LFS". Because no matter how you look at it, racing LFS is still vastly different from the real thing - being fast in LFS has not all that much to do with being fast in real racing.

Anyhow, even if you reach a real barrier, at the current state of development I'd be wary of analysing LFS' WR setups. Most of them exploit physics inaccuracies or the fact that damage is far from being finished in LFS. I very much doubt fast setups in real life all run on the softest tyres possible with a locked differential.

definitely (on all counts), and therein lies the challenge in analysis - to separate what's LFS-specific and what is generally applicable. this is the kind of stuff i really enjoy figuring out just like in looking at RL datalogs, one has to keep in mind the context and limitations in order to make the data useful. in some ways i may not want to get TOO good at LFS if it means acquiring habits that are counter-productive in RL. whether that's actually a real concern or an imagined one it's too early for me to tell, but i look forward to learning more.

also of note that hotlapping (which is mostly what i do) is quite different from racing. in the former you essentially have the track to yourself and can make full use of it, whereas in racing there is interaction with other racers, a lot of strategy and a battle of will to some degree there are skills that are common to both but i think overall the two endeavours are different enough as to be treated separately. perhaps it's a personality trait but my preference is for hotlaps, so far - both in RL and in sim. that may change... or not.

Last edited by dpcars, Wed, 21 Mar 2007 17:48.

Quote :

DP, I hope LFS is still enjoyable for you, while preparing everything for the current track season.

I was wondering if you have had a go in either of the LX cars. If so, I would love to hear your thoughts on them, especially compared to your megabusa. From watching your track videos of the car, the megabusa 'appears' to be less razor edge balancing act than it sometimes is in LFS. Granted, setup/reality-vs-reset-mentality/"seat-of-the-pants"/etc. obviously plays a large part.

[ASIDE] Caterhams/Lotus 7's/Westfields have been a dream car of mine for years, in fact they were the main factor in my purchasing LFS several years ago. The power/weight ratios and simplicity of design are hugely appealing to me.

Despite my ~6'2" height, I still continue to research the various clone makers, with goals of building one someday (Caterham's proportionaly larger SV version would be pretty outrageously expensive to import and build). [/ASIDE]

yes, i think LFS will be vey useful. my current strategy is to get familiar with a couple cars and tracks and get to a 'plateu' in terms of laptimes, then download a couple of the world record replays and see where the gap in lap times comes from. certainly something to be learned there. for example, on city long track in UF GTR i'm pretty much stuck at 1:53 flat for now but the record is 1:38 i think. so my guess is that it's not just a matter of refining a few points here or there but a fairly fundamental difference in approach. i haven't looked at the wr replay yet but once i do it will be interesting to see what i discover.

so far UF GTR is probably my favorite car of the bunch, it feels a lot like a real-life mini. i've only tried the LXs briefly, without touching the setups, and my initial impression is that the stock suspension setups are quite soft which makes them pretty hard to control. but again this is only an initial impression without much analysis so take it as such. the megabusa had 'race suspension' from westfield - adjustable nitron shocks and fairly heavy springs (not sure of the rates i'm ashamed to admit). i had it set up with a lot of rebound damping so it was very planted, kind of felt like a 'wet rag' in a way - in a good way, that is. no tendency to bounce or overshoot the inputs, just does what you tell it to and no more. it had a fair bit of toe out at the front (2mm total?) and about 1mm per side toe in at the rear. also a/r bars at both ends. total weight was 1050 lbs with half tank of fuel (no driver). it was a very quick car. turbulence would get NASTY above 110 mph though, seriously knocked my helmet around. the guy who bought is is 6'2" and it was a challenge to get him to fit. but he did. if you build a kit you could make some mods to ensure you fit in it. there is an outfit in BC, canada, that puts hayabusa motors in caterhams with large frame. i think the cost is around $50K-ish but that may have changed since i last looked.

my goal is to still keep it relevant to rl. based on what i've seen so far the sim has very accurate car behavior so what i'm trying to do is figure out which clues i should use so that it helps my rl driving rather than just learning to drive the sim. at this point i think that's very doable. i believe the sim could be a useful training tool for drivers in the off-season or just between track days, especially as far as predicting what the car will do goes. we'll see.

tried rallycross a bit, it's quite entertaining

i spent some time playing with FZ50GTR on south city long track. definitely have a much harder time with RWD than FWD for the moment. was able to get in a couple 1:46 laps (whenever i could complete a lap without crashing, which still isn't very often ) but it's a handful. the car in the sim does throttle-steer just like in rl so it's a matter of me getting used to it. again it's proving educational because it's making me closely examine what i do, when and why. getting the FSAE car under 2:00 took some doing too. cool stuff. i love the variety of cars and tracks in LFS, and i haven't even tried rallycross yet. some hillclimbs would be really cool!

the dp1 has only run on a local kart track and PIR (http://www.portlandraceway.com). looking forward to doing more testing soon, now that track season is starting back up again here

ah, cool. thanks.

Quote from zeugnimod :

Press 2 and it asks you for a name for the replay. You can chose to watch it under replays on the main menu screen or open it from your spr/mpr folder.

the replays i saw (is there a way to get in-car view for replay?). i meant saving it as video. haven't found that functionality yet, if it's there

i figured there's a way to save the playback but haven't looked for it so no at this point i don't know how. i really haven't spent much time with lfs yet - just trying to see what it's about. haven't touched setups or any of that stuff. to me doing the videotape was the easiest because i already have the whole process down. i'm sure after learning lfs better i'll be able to do more with it. so far i've been trying to figure out if it's worth the effort and the verdict is a definite YES! but, again, i have to juggle many priorities....

LFS is a lot of fun to push the car in - just the thing after spending a couple days swearing at aeroquip hose ends on the atom. now that i'm getting a bit acclimated to it, i've spent about an hour playing with the UF GTR on the south city long circuit. turns out the car can be pitched in and drifted just like my rl mini - and no fear of consequences! it was so much fun i decided to videotape a bit. got it down to 1:53.21 for the long circuit and decided to call it a day.

just got done making the movie (damn autofocus on the camera keeps hunting, just like on rl cars - ugh ) - you can see it at http://www.dpcars.net/lfs1.mpg (warning, it's an 18M file so can take a while)

Last edited by dpcars, Sat, 17 Mar 2007 07:35.

after looking at it a bit more, the hethel run is actually a good illustration of why i don't really like street driving. the car is not getting pushed all that hard - max braking is only about 0.5g and most of the time it's around 0.3g max. max lateral g comes at speeds of around 25 mph. and yet the run is quite risky in legal terms (doesn't look like it was dangerous in any normal sense).

the attached pic shows one of the corners. there is some mild deceleration leading up to it (about 0.1g, maybe engine brakng?) from around 44 mph, then a 0.35g stab of the brakes at 34 mph followed by 0.25g decleration down to 25 mph. at this point there is a right-hand turn building qickly to .94g lateral. at the same time there's about 0.1g acceleration into the turn followed by what looks like a mid-turn shift (a dip in longitudinal accel followed almost immediately by a dip in lateral accel, presumably due to lost traction when clutch is let out? - just guessing here).

all this looks like a pretty entertaining street drive but if this were a racetrack the graph would look very different. one could brake much harder and later, carry sustained lateral g at higher speeds and spend a lot more time at full throttle.... makes me grin just talking about it

Last edited by dpcars, Fri, 16 Mar 2007 16:24.

myself, i'm not a fan of pushing hard on public roads. too many variables, too much risk. these days i try to minimize my street driving/riding although i would have to admit to occasionally breaking rules. it's getting less and less frequent though. just not worth it to me. fortunately the racetrack is convenient and accessible and there is also karting (and now lfs ). but, we all make our own choices.

for what it's worth, there HAVE been real cases of police prosecuting people for driving that they post online or show in videos - most famous was the japan ferrari club president when he started selling a video showing him going at ridiculous speeds in traffic in his f40... chances of it happening in this case are extremely low of course.

applying power in corners is very easy. it does tend to straighten the line a little but it's not understeer as such as it is not due to front wheels pushing but to the diffs getting partial lock under power. the car is very controllable on the throttle and you can widen or tighten the line with the right foot. of course the production car will have a lot more power so the effect might be greater, but then the center diff setup will be different too. we'll see.

as far as brakes, unfortunately on the prototype i'll always have to be careful with them due to diff-mounted rotors. braking locks the diffs also therefore the car wants to go straight under brakes. in other words, trailbraking is out unless you enjoy spins production car will have more conventional 4-rotor inboard setup.

Last edited by dpcars, Wed, 14 Mar 2007 17:58.

Quote from Hallen :

Uh, and who exacly does like it?
Cool stuff Dennis. If the software is free to try, then I will download and take a look at some of this.
Still have to get a helmet...

the software is free to use and it's a full-featured version - guess they hope you'll buy their hardware. i did.

get that helmet, there are lots of good trackdays coming up. alfa 24th, porsche 27th, lotus 3rd, bmw 6th...

it was a case-sensitivity issue with server and filename - try again now, should work.

here are a bunch more:

for PIR:

- the mini on heavy 17" wheels and kdw2 street tires - wheels/tires make a huge difference! - http://www.dpcars.net/misc/mini135_7.run - best lap 1:35.7
- exige on 048 tires driven by ex formula atlantic racer - http://www.dpcars.net/misc/scottexigesolo.run - best lap 1:32.8
- modified cayman S (suspension, rollcage) on R compounds, exp driver - http://www.dpcars.net/misc/caymans.run - best lap 1:31.1
- national champ level driver in a stohr DSR - http://www.dpcars.net/misc/dsr.run - best lap 1:12.0 (this would qualify 10th for ALMS prototype!)
- mcoupe, coilover suspension and R compounds, exp driver - http://www.dpcars.net/misc/mcoupe.run - best lap 1:31.1
- race-prepped wrx STI, SCCA nationals race qualifying (qualified 2nd) - http://www.dpcars.net/misc/sti.run - best lap 1:27.7
- me driving my elise, stock, goodyear street tires - http://www.dpcars.net/misc/dpelise.run - best lap 1:33.4
- for laughs, my stock scion xB, street tires - http://www.dpcars.net/misc/scion.run - best lap 1:44.4


for pacific raceways (formerly seattle international raceway and kent before then):

- me driving the m5, completely stock, street runflat tires - http://www.dpcars.net/misc/m5.run - best lap 1:39.4
- me driving a honda-powered 245hp atom (someone else's car so taking it reasonably easy) - http://www.dpcars.net/misc/dpatompr.run - best lap 1:44.8
- modified 993tt on race tires, driver unknown to me (but supposedly quite experienced) - http://www.dpcars.net/misc/993tt.run - best lap 1:39.0
- modified elise (200 lbs lighter than stock) on AD07 street tires, exp driver - http://www.dpcars.net/misc/elisead07.run - best lap 1:41.8
- me in my mini, stock, bfg kdw2 street tires http://www.dpcars.net/misc/minipr.run - best lap 1:45.9

here's another set of data - an exige on track tires driven by an experienced driver (he used to race formula atlantic among others).

http://www.dpcars.net/misc/scottexigesolo.run

btw the start/finish line is halfway down the front straight so that is where the lap marker should be drawn. a screen shot of the comparison is at

http://www.dpcars.net/misc/datalog.jpg

yep, it's the DL1. love it. a very good educational tool. i've uploaded some sample data runs:

http://www.dpcars.net/misc/dp1pats.run - dp1 at a kart track
http://www.dpcars.net/misc/dp104.run - this is dp1 first track outing
http://www.dpcars.net/misc/mini132.run - for reference, this is my mini on R compound tires.

if anyone wants to play with the files, the software to do so can be downloaded for free from http://www.race-technology.com

the interesting thing is to compare the dp104 run and the mini132 run. in the mini i'm pretty much dialed in and you can see that when i get clear laps i knock them off pretty consistently. at this pace (1:33-ish) i pass most people on the track including instructors in porsche GT3s and it is a little faster than my best elise time on street tires. on R compounds the elise/exige can do about 1:31 but most i've seen out there run 1:35-ish. the dp1 i'm only trying to get an idea of what it does and i only had one clear lap.

the really educational part comes from looking at various spots on the track. for example it's clear that the dp1, even in prototype 4-cylinder form, with only 30 miles on the engine, accelerates pretty well especially coming off the turns. i'm not using anywhere near the capability and yet already that's where most of the lap time comes from. on the other hand notice i'm very tentative with the brakes and brake way earlier and gentler than in the mini. that whole brake-on-the-diff thing is not in the 'success' column i'm also not using the cornering as much as i could, only 1.3 g whereas on the kart track i've seen up to 1.7 (in the run i uploaded i think it only goes to 1.55).

so the mini is pretty much tapped out but the dp1 is only getting started. i expect i have over 10 sec to gain out there this summer. won't happen all at once though!

Quote from ajp71 :

Ultimately though just like in real life planning ahead and pre-empting what the car is going to do is the best strategy, probably more important in a LFS than RL.

very true! that is indeed the essense of car control.

just had my first trackday of the year. i must say, there is something almost embarassing about how good a fast lap feels. there is a certain 'g-high', i first experienced it when doing aerobatics but now that i'm going fast enough in cars i get it here too.

this is all very educational. lots of new information, lots of things to ponder. i'm definitely the better for it.

Quote from KeiichiRX7 :

i recognize that view...... are you wearing the helmet cam?

nah, just holding a digicam at eye level. it does end up being the same view.

i feel like i need to have some real progress on the cars to post about before i post about lfs

but on the subject of lfs, i've been messing with tweaks and things are better. the biggest problem i'm having right now is detecting when the back end is about to step out on a rear-driver. sensing the rear slip rate is totally a seat-of-pants thing and i have not yet figured out how to clue in on it in the sim. trying not to spend TOO much time on it though. been wrapping up some projects for clients so i can get back to the cars. but i'll definitely continue to experiment wth lfs.

and no, you won't see me playing online for quite some time.

Quote from wark :

Donnie Darko

Cool setup.

good eyes! also box sets of lain and last exile...

well, now that i have the wheel set up and working, it's like learning to drive all over again. the major revelation is just how much i rely on 'seat of pants' inputs in real life for car control. the g loads, the slip at either end, car rotation, etc. of course a simulator cannot reproduce all of those (yes, i'm aware of the force dynamics 'pc peripheral' ). so i've been working through the training lessons. i can definitely state that i'm not a 'natural talent' at sim driving. but i'm getting better - most lessons i'm now doing at 'quick' status though none at 'pro' yet. i have maybe an hour total sim time so far. now that i'm getting better calibrated to the feedbacks that are there (wheel ff, sound, visual) i can begin to make up for the missing ones.

it's definitely educational and i continue to be more and more impressed with lfs. very cool.

negative opinions don't bother me - that's a fact of life when one puts his work out there. some people won't like it and some will bash it for various reasons. when criticism is useful i take it under advisement, when it's just ignorance i ignore it. there was a long thread on a design forum about my car a couple years back - if you have the time it might be an amusing read

http://boards.core77.com/viewt ... postorder=asc&start=0

many of the links are now dead but it still gives you an idea of the range of opinions out there. it ended up being a valuable thing for a couple reasons - the most important one is that i realized that styling is a very subjective thing and having easily replaceable bodywork could be a very good thing. so the production chassis has been designed with that in mind.

also, i got a couple alternative designs out of it but neither is really useful except to post some pictures. i did learn a lot from people's reactions to the other designs as compared to my own so it was definitely worthwhile. market research for free. overall though, it proves that it's easy to criticize, difficult to come up with your own alernative and VERY hard to actually make it real.

ShannnoN,

i suspect the devs will do what they feel is appropriate when they feel is appropriate. i'm sure they can manage their priorities and the idea that a forum thread can 'blackmail' them into doing something they don't want to do is a bit of a stretch, don't you think?

on the other hand, most designers take user opinion into account and perhaps this thread is an indication that IF and WHEN the devs decide to include the car it would be well received. i was not hinting at anything when i said it would be cool to test the dp1 in lfs, i meant it exactly at face value. IF it happens, it would most certainly be very cool. i'm certainly not going to 'whine' if it doesn't happen, nobody has promised me anything nor do i feel entitled to have it happen. but i would be thrilled if it does.

i for one am very honored that people take such interest in my car. i've put a lot of myself into it (and continue to do so) and it is gratifying that some find it worthy of attention. still, keep in mind that in terms of development phase the dp1 is still in 'alpha' - it's not even a 'beta' yet. so there's much to be done still and much can change. to a degree, people's reactions to the car (both positive and negative) help me continue to evolve it. so i find this thread quite valuable.

and, through this i discovered lfs

i'm with you on turning off the tv - i don't even have one. only seen tg when friends send me links to online clips.

Last edited by dpcars, Fri, 2 Mar 2007 19:36. Reason : typo

thanks everyone - it'll be a while before you see me racing online but it'll probably happen... for the sake of my projects, hopefully not TOO soon

Quote from 96 GTS :

And I'd just like to be the first to say good for you You're gonna enjoy it, just make sure DP1 progress doesn't come to a grinding halt

thanks. that's always the danger isn't it

i shall endeavor to move forward. have plenty of motivation.

ok, just got my S2 license. had to get a new driver for my graphics card but that was fairly straightforward. just checked out the training stuff with the mouse and keyboard - i must say the sim is VERY impressive. so i went and ordered the logitech G25 wheel/pedals. can't wait for those to show up!