Help me win at autocross, I wanna be a top 10 car and driver! Options

[crash914]

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..

[jhadler]

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