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Posted by: crash914 Jul 1 2014, 06:49 PM

ok, I need help. currently I am about 3 to 5 seconds off the pace in my local club events. I know most of the time is due to the driver. I think that there is some time in the car also as it is mostly set up for the long track.

Here is what I know so far, if more info is needed..ask...

73 914, blue. bolt in cage, just the 4 plates plus the seat belt for tie in points.

stiffly sprung, Koni yellows, I think 250 lbs in the rear and 21 or 23mm torsion bars in the front.

Delrin bushings everywhere, I have needle bearings, just not installed.

lowered, see pictures for height. 4 inches in the rear to the bottom of the engine mount bar, 4 inches in front to the bottom of the front floor pan.

205 50 15 tires, not sure of the wheel width, 4 lug.

my tires are about 8 year old khumo v710's that have been in the garage and have 4 autocross days on them now.

air pressure I have been running, 22lbs front, 20 rear. see pictures for chalk. looks like I am using all the tread.

Camber is close to -2.4 degrees front and rear. Front toe is 0, not sure about the rear, perhaps 1/4 inch toe in.

Motor is 103 by 80, nickies, split cam, le200 heads, tangerine header, 6800 rpm redline, 11:1 compression, so plenty of grunt.

Megasquirt with twin throttle bodies.

Transmission is open diff, with a flipped 5th gear for 3rd and standard 5th.

no camber plates,

See pictures in the following posts..

Posted by: crash914 Jul 1 2014, 06:56 PM

pictures....

Posted by: crash914 Jul 1 2014, 06:58 PM

Video of the loose nut....I had a good run until the cone jumped out in front of me....

https://www.youtube.com/watch?v=54uULzcLg4s

Posted by: koozy Jul 1 2014, 07:02 PM

1- Lose as much weight as possible (car and driver)
2 - Toss the old tires and get some Hoosier A6 tires under there (wide as ya can fit)
3 - Get some toe out in front
4 - Get the car corner-balanced and make sure you are not running the car too low (a-arms and axles need to be parallel to the ground when static)
5 - Lose more weight (if it don't make ya go faster take it out)
6 - You need to know what the spring rate is up front to balance the suspension so guessing on T-bar size won't cut it.

That should make a HUGE difference

Posted by: crash914 Jul 1 2014, 07:08 PM

I know about the weight thing...I did corner balance some time ago...I am going to do it when I replace the bushings.

I did forget...no money...got to be done on the cheap...this is still a street/track car...

I am about 1900 lbs now without driver.

I agree about the tires...old rubber...but, no money!
The car is pretty balanced, I can throttle steer very well. I did get lots of understeer when taking that sharp left in the video, but was just too hot into the corner. Otherwise, both ends let go pretty much the same....
Is my air pressure too low?

working on the driver weight....got another 25 lbs to go...
thanks!

Posted by: koozy Jul 1 2014, 07:23 PM

If you machined the Delrin bushings properly and lubed them prior to install they should work fine. Bearings will be better but properly installed Delrin is light years better than rubber.

I just watched the video. You are coasting too much. If you are not on the gas you should be on the brake. Those tires are probably worse than soft compound street tires at this point. You are overwhelming them with little to no effort. Also, you are in third gear where you could probably be in 2nd most of the time. Find some fast drivers and ask them to get in and instruct you a bit. Then, seat time is your friend.

The "no money" thing will keep ya from the pointy end of the field, if for the lack of competitive tires alone.

Good luck in your adventures.

Posted by: mskala Jul 1 2014, 07:24 PM

I sure as hell don't know everything, but:

1) It looks like there are several places there where you are coasting up to
the braking zone, when you should be full on the gas and then hard on the brake
(these look like straights in the video, if not then my bad, but you will still need to
push the limits more)

2) I'm in favor of hands at 9 and 3 (ish) and if a corner gets too tight, you leave
the outside hand in position (but it can't grab), take your other hand off, move it
across and pull the wheel the rest of the way. This way you will always know where
the wheel is. Easier to show than to explain.

If you are that far back as far as times you're getting vs. your goal time, then keep
those tires if they haven't aged out while you improve.

Posted by: koozy Jul 1 2014, 07:27 PM

Also, this book is money well spent.

Secrets of Solo Racing: Expert Techniques for Autocross and Time Trials

http://www.amazon.com/Secrets-Solo-Racing-Techniques-Autocross/dp/0962057312

Posted by: koozy Jul 1 2014, 07:30 PM

Hand technique is explained in that book. Get a tire money jar and throw $5 every chance you get. Do a side-job or something. Tires are critical in this game.

Posted by: koozy Jul 1 2014, 07:35 PM

Also, tire pressure should be slightly higher in the rear than the front due to weight differential. I would swap those tire pressures front and rear

Posted by: Alice Jul 1 2014, 11:25 PM

What about a new set of good race shoe s ?

Posted by: crash914 Jul 2 2014, 02:56 AM

all good info. Thanks!
I know I need rubber, but I figured it would be worth 1 second or so...not 5..

As far as 3rd gear, you are right. this was a long 911 course, FTD was a cayman with a 42.something. I was 47.x

the previous courses, I tacked out at 6500 rpm several places..thus the pull in 3rd gear. I was about 4500rpm in 3rd. Remember it is a flipped 5th gear.

I did have on my lucky autocross shoes.

Since I have a full set of Shine suspension bearings, I am going to install them...then I will know my T-bar size and sway bar.

I do really like the idea of a solo instructor...thanks for looking at the videos....I learn a lot from everyones videos also.

I will post the link to the FTD video of this event..you can see the difference. I wish I knew how to do a side by side...that would be awsome....thanks all...

Posted by: crash914 Jul 2 2014, 04:17 AM

Here is a link to the FTD...

http://vimeo.com/99539180

Posted by: koozy Jul 2 2014, 07:55 AM

You said top 10. What was the tenth place time?

In your case the tires would be worth more than one second. Sticky street tires would give you a full second over the stones you have on there now. 8 year old race tires have gassed out years ago but are fantastic for learning car control since they give up so easily.

Posted by: Racer Chris Jul 2 2014, 08:17 AM

Your car is already too low for good suspension movement.
The lower CG won't make up for loss of contact patch from the wrong dynamic camber.
You don't really need toe in at the rear for AX. Some toe out at the front will help turn-in.

Posted by: wobbletop Jul 2 2014, 09:04 AM

Keep your hands at 9 and 3.
Get new tires.
Be more aggressive... go for ride alongs with guys that are faster than you.

www.youtubedoubler.com btw

Posted by: crash914 Jul 2 2014, 09:12 AM

All good info...my street tires are 10 years old also....so at least the soft rubber is stickier.

I plan on running these tires this year and will look at wheels and tires for next year...practice, practice and burn them up..

I did have a fuel problem during some of the last runs, my inlet air temperature sensor was flakey and was reading -40 degrees to 140 degrees. Really threw off my AFR.

I really get no body roll. this car is STIFF. the front A arms are just lower than horizontal...but the suspension doesn't move...

could I bee too stiff?

Posted by: naro914 Jul 2 2014, 09:41 AM

Tires, tires, tires... yes, tires can get you more than 1 second. Difference between my soft 'street' tires and A6's is more than 4 seconds. You will be amazed at how well A6's grip. My first time using them, I couldn't hold the steering wheel I went through the turns so fast and held so many G's.

Using !6's, I can usually compete for or are within top 5 of FTD in our region with nearly 100 cars running - some purpose build SCCA or full track cars. Without them, I am middle of the pack...top 30 or so...

And NO COASTING....gas, gas, gas...brake brake brake. One or the other...never neither.

Posted by: drgchapman Jul 2 2014, 10:52 AM

As a driving coach, I find the most time can be made up by working on the driver and his habits.......
Check out evolution driving school, very good instruction for autocross.

Posted by: crash914 Jul 2 2014, 11:09 AM

ok, see this thread is helpful already!

Chris, what do you recommend for ride height? A-arms horizontal?
I have our next ax mid July...hopefully I can have some of these ideas in place...

I am currently top 20, around 16 to 18th. this years goal is top ten, then for next year......I might have to run with the big dogs...just for fun. my problem is my motor pushes me out of any stock or improved class...I have to run modified..its all good though.

I would like to go to one of the driving schools...I feel that would be the biggest bang for the $$....
thanks all...

Posted by: Woody Jul 2 2014, 11:49 AM

Everyone touched on some really great points. I don't have much to add except try to keep it in close to the key cones such as sweepers and slaloms. Here is a couple of vids from earlier in the month. I had a bunch of trouble going into the sweeper because I couldn't heel toe with my new shoes and it cost me a bunch of time.

https://www.youtube.com/watch?v=TE4QWNzKhys&list=UU_9lnpWmWm8bK1V5SXqdhrQ

Keeping it in close.

https://www.youtube.com/watch?v=o5LXqWb2YAY&list=UU_9lnpWmWm8bK1V5SXqdhrQ

Posted by: naro914 Jul 2 2014, 12:14 PM

Couple quick videos:

https://www.youtube.com/watch?v=N0E67YE7Js4



https://www.youtube.com/watch?v=523pRL0QETI


Looking at them back to back, they look like pretty similar layouts, but the second ran 1/2 of the course twice...

I don't do 9 & 3...I shuffle steer... A LOT as you can see. First video I got 3rd from FTD, second one I got 2nd..

and yes...no need for 3rd gear in your videos. Keep it in second. All the power is at the higher RPM range..

Posted by: crash914 Jul 2 2014, 12:16 PM

NICE! I like the low camera angle..

Posted by: mskala Jul 2 2014, 01:02 PM

Me on saturday. Our courses tend to not have super tight corners or you
would see the steering technique. I was second only to a modified GT3RS.

If your car is super stiff, but the pavement is smooth enough, that is not a
bad thing. I'm using 180lb springs as my car is a street car, and it rolls all
over the place.


https://www.youtube.com/watch?v=PABjDKH_Upw

Posted by: crash914 Jul 2 2014, 04:13 PM

If I remember, you were always smooth and fast at devins...
The course here is usually bumpy, with good pavement and then loose choppy stuff...
they are mostly set up for the 6 cylinder crowd...I like a tighter course..

Posted by: jhadler Jul 2 2014, 06:20 PM

Herb,

I'll address this in two parts: The steering nut, and then the car.

First and foremost... SEAT TIME, SEAT TIME, SEAT TIME. You need to get a lot more time behind the wheel to catch the front runners. Don't sink investments (that you have admitted you don't have) into the car until you are finding the limits of the car everywhere on the course.

As for the car... TIRES. The rocks you're on will be great for learning, but are probably keeping you back at least a second, maybe two. Don't take this to mean you should go out buy new sticky race tires right now. The only that will do for you is make you go broke. Old rock race tires are GREAT for learning on, and you need that. New drivers on fresh race rubber quickly discover how intolerant race tires are to mistakes. And it is not uncommon for a new driver on fresh race tires to destroy a $1000 set of tires in one weekend.

A common error for new drivers is to go too fast in the slow parts and too slow in the fast parts. Others have touched on the GAS GAS GAS issue. If you are not using as much throttle as the tires can handle, you should be on the brakes as hard as you can, for as little time as you can. And from the video I can only hear a few places where you're really getting hard on the gas. For that course, it (full throttle) should be audible in many more places. Oh, and use the full rev range of the motor, you're short shifting too much. That's the going slow in the fast parts. You're also going to fast in some of the slow parts. When you dive in too hot, the car will push, not turn, and then your first instinct is to turn in harder, and then you get even more push. Slow down when you need to go slow.

Autox is about TIME, not SPEED. Spend as little time in the slow turns as you possibly can. This means: enter controlled, get out fast. If you go in too fast, you will push, and spend even more time there trying to get around the turn.

An age old saying from racing applies: "Better to go in slow, and come out fast, than to go in fast, and come out dead.".

And now the car:

As noted, you've got rocks for tires. And that'll hold you back on time, but you've also got a lot of prep in the car while still running on 205's. The front runners in most regions will have made an investment in getting as wide a tire under their car as they can. Usually this will mean widening the fenders to accommodate larger wheels and wider tires. A stock bodied 914, is limited to 205's, and that will also limit how far up on the time sheets you're going to be able to get. Want top times? Gonna have to pay if you want to play.

Suspension:

You don't seem entirely sure of what's in there. Suspension is everything in autox car prep. Engine is a *distant* second, again this is about TIME, not SPEED. Make sure you know what you have right now, and get it working as well as you can.

Bushings - Mentioned before, but delrin alone may actually be a hindrance if not properly installed. You need the suspension to free of binding.

Springs - You use "I think" in describing your spring rates. You really should know what you've got. If you've really got that much spring in the car, especially if it's as light as you claim, you may very well be over-sprung. Too stiff, and the car will not behave well. Even more so if you don't have the sticky tires to get the suspension working.

Sway bars - no mention here of what, if any, sway bars you have. This will make a really big difference in how the car is set up.

Shocks - Koni Yellow are fine. Set 'em for now and then forget 'em. Don't mess with settings right now, it'll only make the learning curve steeper. Learn to drive the car you have. Then start making small changes, one at a time. You'll find that once you're really getting the car to the limit -everywhere- on the course, small set up changes can become much more noticeable.

And now ALIGNMENT.

You mention -2.4 deg camber front and rear with no camber plates. I'm skeptical. It takes some work to get that much negative camber in a 914. You also make no mention of caster in front. Caster is king. More is better. Caster is dynamic camber. The more the wheels are turned, the more negative camber they gain. Toe is okay, a tiny bit out in front. Neutral to a tiny bit in at the rear.

Corner balance the car, you may find you actually need to raise the ride height a little. That's okay. Too low and you get funky behavior of the suspension (bind, bad camber curves, etc).

I think that'll be good for starters...

Oh did I mention SEAT TIME, SEAT TIME, SEAT TIME??? Drive every chance you get. Ask to ride with other experienced drivers. Ask them to drive your car. You'll be SHOCKED at what an experienced driver can do behind the wheel of your own car.

And HAVE FUN!!!

-Josh

Posted by: crash914 Jul 2 2014, 06:35 PM

Thanks Josh...good info..
I do now have flairs on the car...tire width is no problem. I am running keiser wheels but need to get the back space measurement.
Front sway bar is 22 mm. Stock rear sway bar. I put the coil overs on the rear, but just don't remember the spring rate. Did I mention I had the car off the road for 8 years? I did not do the cage, T-bars or bushings...done by previous owner so I need to dig deeper.

oh yea, I am having fun...competing with myself. I am finding the gopro the best tool to see actually what I am doing when.
Lots more to learn for sure...you all are great coaches....

Posted by: jhadler Jul 3 2014, 10:03 AM

Are they sparkly?? Sorry, just a bit of end-of-the-week humor. I find myself sometimes a stickler for spelling. Flares are for race cars, flairs are for TGI Friday employees...



4-7/8" or 5" backspace is the maximum the tub can take without excessive rubbing, and even then it might be too much. What width wheel? Do try to find a VERY GOOD tire tech for mounting race tires on those wheels. Keizer's are stupid light, but they're also quite fragile. A gorilla of a tire tech can EASILY destroy one of those wheels with too much grunt in the wrong place...



Aha! Loose the rear bar right away. Unless you've got a limited slip, you're going to find that the best set up will have a strong front bar, stiff spring rates front and rear, and no rear bar. The rear bar is only going to get you wheel spin right now, and with the spring rates you're running, it's not doing you much good anyway.



Have fun!

-Josh

Posted by: infraredcalvin Jul 5 2014, 10:06 PM

Don't make any changes to the car.

Have one of the fast drivers drive your car , I'll bet they'll make it within a 1-2 sec of your target time with no changes except the driver. If you can ride with them in one of those runs, even better. Watch their lines/technique, etc. all great comments above, but learn how to drive first, constantly tweaking your car while you are trying to learn is just going to extend your learning curve. Take notes, videos, review them.

Once you get close to those times, then start making tweaks 1 at a time - make a small tweak, see what to does, another, then test... You'll get an idea of what changes have the maximum effect for your driving style.

Good luck have fun!

Posted by: koozy Jul 6 2014, 06:47 PM

I agree, working on driver skills is the single most important thing you can do. But, I caution you on doing it in a car that has basic setup flaws. These are simple fixes that can have you learning how to drive better and reach your goals faster instead of learning how to drive around basic setup problems.

Posted by: crash914 Jul 7 2014, 02:48 AM

The car is fast and easy to drive...very neutral.
In the last video autocross I ended up at 21st out of 63 cars...I am about 2 seconds off 10th and 4 seconds off 1st...long way to go.

So for the next event, loose the rear bar, increase tire pressure to 30/32, chalk and see if I am using all the tread. Raise up the front of the car slightly and see if there is any weight transfer improvement.

last but not least...keep my foot on the floor...I am now looking for a led solution that I can wire up. green for on the gas, red for on the brakes....should be easy to see in the video..
thanks all...

Posted by: crash914 Jul 8 2014, 04:36 AM

Here are a couple of pictures...I even show the flairs! They are quite special.


Static shot of ride height





Suspension is stiff...these are with the rear roll bar attached and low tire pressure.
I can see that I am off the cones and turning/braking late...

Posted by: mskala Jul 8 2014, 06:53 AM

I don't remember any recommendation to go to 30/32 tire pressure, only to avoid
having more pressure in the front than the back. For reference, I was running the
V710 up until this year, at 24psi all around, and my car is heavier than yours.

Posted by: crash914 Jul 8 2014, 07:45 AM

I was looking in some old threads about the V710's....they were from 2005 about the same age as my tires...

I think that my pressure is too low now at 18/20 as my rankings have slipped. think that I will try a higher pressure next time..
I will chalk to see where I am. Perhaps the chalk sent me down the wrong path...My first event was run at 24 everywhere based on what you were doing...going to try it again..thanks

Posted by: koozy Jul 8 2014, 08:37 AM

Chalk will get you nowhere with those tires. Chalk is used on bias ply tires to determine rollover but in single run autocross you can easily see this without chalk.. Radials such as the V710 do not tell you much when chalking due to their construction. Forget about the chalk. Set the tires at a known, neutral tire pressure such as the suggested 24/26 front/rear and see how that feels. Toss the rear bar on a shelf in the garage.

Posted by: crash914 Jul 8 2014, 09:08 AM

got it! oh and have fun!

Has anyone ever seen a throttle/brake light indicator for Ax?
I will try to hook up something to my megasquirt for the throttle, I guess somewhere above 80% and to my brake light switch....that way I can see when I am on the gas/brake....It would be nice to find something already in production....

Posted by: koozy Jul 9 2014, 08:30 AM

Your money is better spent on tires.

You can hook a light up to the brake switch and set it so you see it on the video. That will help but only if you remember to apply it on the course next time you drive. Everyone learns a little differently. You may benefit tremendously from that. Though, once you get the hang of it you will know by looking and listening when watching the video, little red light or not. Look at them enough and you will know.

Just set the basics on the car and drive. There ain't no smoking gun here. Drive the piss outa that car. Judging by that video, you ain't doing that yet.

Posted by: koozy Jul 9 2014, 08:41 AM

When is your next event?

Posted by: crash914 Jul 9 2014, 10:05 AM

the next events are July 19th, Next Saturday and then Sunday July 27th...I will by driving balls out....no doubt about that...

Posted by: Racer Jul 9 2014, 07:42 PM

As a Potomac member I will chime in with some other things..

1) The lot is hard. Low grip. imho, if you are not on the knife edge of slip angles, you will not carry any speed.

2) For me, AX is an on/off switch.. don't feather shit.. just bam on and bam off.. gas, brakes etc.

3) I found running same pressurs front/rear was the best place to start. imho, 20 is too low. I always preferred 26-28 all around.. sometimes even 30 all around.

4) would love to take a ride and help out if I can get to an event this year.

The new cars have tremendous advantages. Bill C or Vrankovich in their Caymans are very good drivers in a nicely set up car. 275+ width R comps or Hoosiers will make anyone fast. As mentioned, new soft 205-50 rubber would drop 2 seconds for you. The new cars also have a rev advantage (say 68-7500rpm.. means less gears needed.. less errors in shifting too..

Seat time is the best advice... get more and more.. Run Chesapeake and Potomac events.. maybe SCCA (badly classified) and Capital Driving Club too.

Posted by: crash914 Jul 10 2014, 03:03 AM

Thanks Dave! you are welcome to drive anytime...I know I won't be as fast as Bill or John, (we are in the same class!) so I just want to be top 10. I am running both chesapeake and potomac events as they are pretty close to me..Not ready for the others yet until I get new rubber..next year!
Swing by and say hi!
herb

Posted by: crash914 Jul 21 2014, 09:02 AM

Latest runs, crappy cell phone video.

Ok, looks like I still spend too much time coasting and am braking late and on the throttle too early...



https://www.youtube.com/watch?v=U9E5_3dCO28


tire pressures were 30/32 I did drop to 29/31 but went slower. I guess I will start higher next time.

Front ride height was bumped up so my control arms are horizontal.
Rear sway bar removed.

Overall, the car felt very good, still a little loose in the rear. The front stuck like glue.
Mostly loose on throttle.

thanks for watching....

Posted by: koozy Jul 21 2014, 02:05 PM

Looks much better. There are places you will NEED to coast a bit. Don't let that bother you. In some places it is the faster way around. When you learn better throttle control you will be on throttle in the coasting spots but slowly, and controlled. I would say the loose rear is too high of tire pressure. I suggest going lower before going back to the higher pressures. In my opinion, your pressures are 5 pounds too high.

Do you have the ability to lower the rear ride height?

Posted by: koozy Jul 21 2014, 04:22 PM

Coasting is ok, sometimes. This is my run from Saturday. Though, mostly it is a feathering of the throttle when ya need to.


https://www.youtube.com/watch?v=zBBhj3Cybjw

Posted by: koozy Jul 21 2014, 04:26 PM

I looked at your video again. You need to get used to the brakes. Get where you are going, in a hurry, and stomp on those brakes. Find where they lock up and learn the threshold just before lockup. This way you will have more confidence to charge into corners.

Posted by: crash914 Jul 21 2014, 05:17 PM

Thanks Mike,
I think you are right. Looking at my g data, I am pulling much more in turns then on decell. I am still used to the street tires that lock up too easy. I never locked up the fronts and I think I can still keep more speed through the corners. Throttle, I am just about maxed out. I did go to 3rd again as I was on the rev limiter halfway through the straight. It seems to help me to brake and downshift. I just seem to be able to put it together better.

I do have coil overs in the rear. you think I should go lower? I can also stiffen up the front bar. I am about 3/4 soft now.

Thanks agin..

Posted by: Racer Chris Jul 21 2014, 07:05 PM

Keep adding front bar until you don't like the understeer.

Posted by: koozy Jul 21 2014, 07:34 PM

What size front bar do you have and how old is it?

Posted by: crash914 Jul 22 2014, 02:54 AM

front bar is 22mm...how old? it came with the car...I would guess early 2000's

somehow I misread Marks post on tire pressure....looks like mid 20's to 30 should be the ticket...next event next sunday...

Posted by: koozy Jul 22 2014, 11:02 AM

Yea, I'd start with trying to maintain 24psi front and 26psi rear before doing anything else to the car. Start there and bleed down as the tires warm up and the pressures go up. This will likely tame the wild rear end. Then, when you get used to that, a couple of events worth, you can fine tune with the bar if needed. Start saving for tires for next season. Even if it is a jar with pocket change and a five dollar bill every once in a while. Start now and you won't find yourself without competitive tires next season. We'll get ya in the top ten, eventually. How many seconds off of the tenth driver are you now?

Posted by: crash914 Jul 22 2014, 11:18 AM

yep, tires are on the agenda...results won't be posted for a couple of weeks????? but I was around 52 and change ftd was a 49 something. a couple of stock boxters were 51ish. FTD was a turbo 911.....

Posted by: mskala Jul 27 2014, 08:28 AM

Herb,
See about 20 sec in for how to avoid shuffle steering. I always know
exactly where the front wheels are pointing.


https://www.youtube.com/watch?v=9BQ0Kn97vwg

Posted by: crash914 Jul 27 2014, 04:46 PM

Looks good Mark, I will have to give that a try, I was having some problems with the over 180 degrees stuff when I tried it...

video to follow, but today I think i am within 1 to less than 2 seconds from FTD.. Got beat by another 914 that came to play..oh well.

getting better and its looking up...thanks guys!

Posted by: J P Stein Jul 28 2014, 10:31 AM

Other Porsches are no competition.......unless you bring a 908/3.
This was true before Brit added 150 hp.
Wanna go fast? Just bring money.
You'll note that smoothness is temporary. Brit has "quick hands" and uses them............that is what it takes from the driver aspect.

http://www.youtube.com/watch?v=oFl0zJtdnQM

Posted by: crash914 Jul 28 2014, 12:39 PM

Yep, no cubic $$ here....that is why I only want a top 10...
here is a video of my first run...you will see where I missed the gate..it was fast though!


https://www.youtube.com/watch?v=oaEsjb5Mx70


my last run should be up soon, faster, smoother but alas no data stream....oh well, need more fancy stuff...

Posted by: crash914 Jul 28 2014, 02:51 PM

Ok, here is a video of my fastet run. I just need to go faster! The data logs of my runs show that I was only about .8g's in the turns and i never hit the rev limiter...

I think one datalog showed 1.4 g's though...must be wrong...As you can here, wheel spin on acceleration is a problem also..that is down to needing tires and LSD..again, $$


https://www.youtube.com/watch?v=hq_bW_IQ63Y

Posted by: mskala Jul 28 2014, 03:49 PM

Looking better. I don't follow these courses as well as the more obvious runways.
Hard to tell from the vid how bad your tires are.

Posted by: Racer Chris Jul 28 2014, 06:52 PM

It looked like you were driving a "safe" line.

You need to lean on the tires a bit more - sideways and accel/decel.

Posted by: crash914 Jul 29 2014, 04:22 AM

The above event times have been posted..damn...11th. out of 53. 1.3 seconds back..FTD by the M3 bmw that started before me....
Getting better however, Steve Lutz beat me in a stock motor prepped 914....by .75 seconds. (with new hoosiers) so a much better driver....

I think I need an instructor to ride along and talk me through my lines and how much speed I can carry. I am still getting a feel for how much grip these tires really have...it is more than I have found yet...hammmm to run this weekend? I just might!

Posted by: koozy Jul 29 2014, 07:39 AM

Tell me about the data overlay. How do you like it and what hardware are you using for it?

Posted by: koozy Jul 29 2014, 07:48 AM

Get the camera outside the car. You can get much closer to those cones and be more aggressive

Posted by: crash914 Jul 29 2014, 08:04 AM

Agreed...I need a camera mount for the outside. I have the rollcage mount for the gopro already..

As far as data collection, I have been trying out lots of stuff.

I am running MegaSquirt, so no ODB2 or other electrical interface.
I wanted to do something with the AIM Solo with Trail brake Matt, but did not want to go to the trouble of installing another data collector...

So, what I figured out is that I already have a bitchin data collector with the mega squirt. I get throttle, Manifold pressure, rpm, fuel flow, AFR and much more. What I didn't have was the GPS data. Palm slap, smart phone!

I added a Qstarz GPS 10hz receiver via Bluetooth, now I can use the phone as a camera and data position collector (no rpm though), I was trying "Track Attack, and RaceRenderHD. ok, looks good. what about my fuel system data? Add Shadowdash for the megasquirt, now I can log everything, speed, G's, rpm, throttle.
Great, but no camera....ok add the gopro and combine both in RaceRender. I am using the free edition now, but will upgrade shortly as it is so easy to use.

I am finding the camera the best tool so far. I can see my hands and position. the data tells me I am nowhere near the limit on G's. The run with data I maxed at somewhere about .8 or .9. I have other data logs up to 1.4...(that is why I know my tires aren't too bad )

Long but I hope this gives you some ideas...

Posted by: jhadler Jul 29 2014, 10:18 AM

At this point, forget all the bells and whistles. Video's nice, but don't go out of your to invest in the technology. What you need is seat time, instruction, and more seat time. Find the local SCCA chapter and see when they're holding their next autox school.

What folks are saying about -smooth- is really important. But smooth does not mean slow. Imagine a chart that shows your acceleration versus time, both longitudinal (acceleration and braking), and lateral (grip when turning). There should never be any discontinuities in that chart line. That means no sharp corners. The slope can be steep, but it shouldn't have any hard corners. The closer you can get to that, the more the tires will grip. Choppy inputs (the discontinuities) are where tires complain, and loose grip, be that under braking, getting on the gas, or turning the wheel.

-Josh

Posted by: ConeDodger Jul 29 2014, 10:23 AM

To improve the driver, do a few track days. Things happen so much slower, though you're going so much faster that you can think your way through cornering - until you don't have to think your way through cornering. Find a good instructor to ride along with you in at least one session per day. Those cornering skills translate to the autocross course. Things happen about 4 times faster on the autocross course though...

Posted by: crash914 Jul 29 2014, 10:42 AM

See the turning g-force chart in the attached excel file....

I can see quite a bit of correction...

Track days are fun, I just don't like the whole inspection process prior to getting to the event..that and I usually break something. I will be doing some track days soon, just might not be until next year..

 2014_07_27_12_modified.xls ( 307k ) Number of downloads: 61

Posted by: crash914 Jul 29 2014, 10:50 AM

fastest time of the day...


https://www.youtube.com/watch?v=_MrSSoG0mlw

Posted by: yeahmag Jul 29 2014, 04:23 PM

Holy crap that's a tight course with lots of things to hit! I consider myself very spoiled running El Toro with OCR.

Posted by: mskala Jul 29 2014, 05:18 PM

That guy doesn't seem to be doing anything special and it's not like a
formula car. So with practice and tires you should be up there.

Posted by: J P Stein Jul 30 2014, 08:59 AM

A WAG.
From the sound of things, the fella in the BMW isn't using R spec tires.
Good driving tho.

Posted by: crash914 Jul 30 2014, 10:18 AM

Hi Jp,
From what he said, it is a stock M3. He did do coil over, springs and bushings...nothing else. I can't remember what he had for tires. I think they were not R's though. When we were talking I did not know how fast he was, young guy...must have mad video game skills...

Posted by: Joe Ricard Aug 4 2014, 07:52 PM

how to drive a 914
https://www.youtube.com/watch?v=MLSm7iC5KY4&index=16&list=UU1B4N-wr6Cv9l3FVS3ade4A

Posted by: crash914 Aug 5 2014, 05:31 AM

Nice, looks real fast!

I am up to 11th...almost reached my goal!

Posted by: karnak Aug 7 2014, 09:24 PM

Lots of great info here. I have some of these issues, but have my car mostly sorted out. I did have 2 sets of the same tires and wanted to use up my older ones. It finally happened. My other set was so much better, I regret not switching sooner. My car, driven by a local PCA member, beat out a GT2.

There, is an interesting example of the importance of the driver.

I am running poly-bronze bushings all round. (In case it matters). I have not seen anyone else mention them here so I am not sure if it it is relevant.

Posted by: Joe Ricard Aug 10 2014, 07:02 AM

as mentioned above and demonstrated in several videos. DRIVER DRIVER DRIVER.

Posted by: crash914 Aug 18 2014, 08:01 AM

UPDATE:

At the last event, after the 1st of 2 run groups I had FTD....

I was shocked....of course all the fast drivers were in the 2nd run group...oh well. I might have a top 5 if I am lucky...
It didn't happen without a video...


https://www.youtube.com/watch?v=8tsfolkY27A


Thank you everyone for all your help! The best comment I received after the event,

"oh, that's your car? You were sure entertaining!' Must have been all the drifting I was doing.....

Posted by: koozy Aug 19 2014, 12:25 AM

Good job. Hard work pays off. Get some of those fast guys from the second run group to hop in with you and get yourself some fresh rubber.