turbosa22c

ok heres the thing. on a autocross course i come up on a tight hairpin type turn or a decreasing radius type turns. the car initially understeers going into the turn. i let off throttle and kinda try to turn in. when that doesnt happen then im forced to tap the brake. and then quikly add throttle to rotate the car. then the car wants to over steer and im bordetrline drifting through the turn. im running 235 front 8" rim 40 psi dunlop dz101,245 rear 9" rim 40 psi dunlop dz101. my alignment specs are stock at normal rideheight. ive lowered the car before the event so i dont know what happens to alignment after that. do you think i should try to play with tire pressures to help with the turn in. or do you think front camber should be adjusted? i want to make subtle changes at a time to get dialed in. what do you guys do?

DaveCM203

I would switch the back to the same size as the frount. The 8 is balanced and so (I believe) that the wider tires will cause a bad understear. I have tried a few different tires on mine and I usualy get a little better results by running the rear a couple of pounds lower than the frount. I am not a suspension expert. There are some guys on here that seem to know what they are talking about. Maybe they could recomend shock settings and sway bars to help. If you have the stock rims still, try them in the next autocross and see how the car reacts. Also, changing your ride hight will dramaticaly effect the camber.

TeamRX8

iTrader: (25)

You'll need to explain your whole setup if you want an accurate assessment. Sounds like you must have coilovers if you're lowering the car; brand, model, etc. etc.

clyde

slow down

turbosa22c

hks hiper rs. dampner set at 20 front, 20 rear. 30 being maxed. the drop is about a 1.5 inchs all around. i believe im losing about a second and a half at least through these turns. on my runs the times are within a tenth from each other. so i think im pretty consistant. just looking for tips to pick up a second or two. another thing is , iknow its going to very from track to track, but when do you recommend shifting. do you just bang it into next gear as soon as torque peaks or do you wait til a certain part of the track where there is room . i know there isnt one correct method, just looking for responses from experiance.

DrifterX

sounds like you you might be turning in to hard causing you to under right at the turn in trail braking might work also your right the tires might work better under different psi i would warm them up and then just lower the psi to see if it helps.

ULLLOSE

iTrader: (1)

The majority of corner entry under-steer, aka push, is driver induced due to entry speed. A byproduct of that corner entry push is usually exit over-steer due to having to overcompensate for the fouled up line and the fact that most times when you push on entry you are now off line and in the dirt when you try to exit and that also makes the car loose.

turbosa22c

so before entering the turn i need to brake sooner or harder to correct my entry speed? or maybe i need to look at my line at that corner. its hard especially when you dont know what your looking at. when i walk the course it looks so different from inside the car.

ULLLOSE

iTrader: (1)

I don't know your driver experience level but most newbies that I have helped tend to way under use the brakes. They will brake generally in the right area but are way to easy on them. When it is time to use them I pound them and then get off.

Just to clarify only pound them when you need them, it is easy to go the other way and brake more often then you need to. After 24k miles and two autox seasons with two drivers in our car we are still on the stock set of pads that came with it new.

TeamRX8

iTrader: (25)

what tire pressures?

DrifterX

just wandering are you using the dsc when you autox sometimes it goes off when you still have full control so i never run with it on but if you dont feel safe with it off leave it on also if you are going to start getting hard on your brakes like real hard i would recomend you get Stainless Steel Braided Brake Line Kit it's keeps the pedal harder then the oem lines and they will never blow under extreme preassure.

PoLaK

iTrader: (1)

Hey says 40psi in his first post front and rear, which IMHO is way to high i like to run 32rear 34 front, or 30rear 32front depending on the surface. This is again on stock suspension/alignment/sways, street tires, etc...

TeamRX8

iTrader: (25)

depending on which tires you have, I might disagree, it really depends on the sidewall stiffness/outer edge rollover.

understand that unless anyone has or is familiar with this particular setup anything said is just a wild@ss guess, but here's what I'd try:

drop the front shock stiffness from 20 to 10 (softer) and drop the rear tire pressures down to 32 psig. If that feels like it's heading in the right direction but needs a little more then start increasing the rear shock setting (stiffer)

tmak26b

Best way to turn in faster is to go slower into the turns! You were understeering because you were going too fast

DrifterX

yes that's true but he's going for - times so unless going slower is the only option working with the tires and suspesion should be the first thing to figure out because you dont want to work for the car you want it to work for you.

TeamRX8

iTrader: (25)

or he could be entering faster if he corrected a transitional understeer imbalance ...

clyde

Perhaps, but given the details he's given in the context he's given them, is that what you really think the problem is?

I'm sure that his setup could be improved, but if he's overdriving the car to such an extent that he thinks he's loosing 1.5 seconds or more "through these turns" there's a lot more going on than his car's setup.

DrifterX

well i read about your tires and those are top of the line so the psi your running sounds like one of the preblems because when tires heat up they go up by 6-8 psi so when heated your must be close the 50 max so yeah lower it to maybe 34 like someone alls said if it's till to much let some air out but dont go to low also when you decided to run that setup did you just jump to those settings or did you test it little by little maybe you should go back to the stock specs the suspension came with and work again from there.

tmak26b

Good luck, set up a car to compensate bad driving

ULLLOSE

iTrader: (1)

You can always set up a car to work around bad driving... That does not mean it will be fast.

A drift setup might work in this case....

No matter what you may have heard from Cole Trickle, loose is not fast. Ask TeamRX8 how that loose car works for him.

TeamRX8

iTrader: (25)

too loose is just as bad as too tight, you have to slow excessively for either ... and in milder cases some drivers are faster one way and other drivers faster the other, it just depends

and anyone who talks on this thread with absolute certainly is really talking out their @ss, you're no more in a position to state as fact whether it's bad driving or bad setup, both suggestions have potential validity in a theoretical forum thread

turbosa22c

yesterday i did an alignment at work. unfortunately the alignment software doesnt have specs below the minimum height stated in the manual. the coilover setup is 1 inch lower than min height in the manual. so i adjusted the front and rear to within specs first. i then set front toe to 0 in. front camber to 2.0(front camber originally was at 1.7) . i'll try those settings at the next autocross.
40 psi to high? how much can a tire heat up in one run. im in hawaii so ambient temp is pretty much consistant. i would estimate its about 15 min between runs.

CosmosMpower

With the stock potenzas I run 30/32 and it seems to work well since the tire has such a stiff sidewall. My first event of this season I ran 36/38 for a few laps and was skating on ice.

DrifterX

(tmak26b) please dont post ***** because it didnt help one bit (power) is right like we said before 40 is high i run that on the streets to save gas but on the track or autox i stick with 32psi works for me i have read the psi lvls after each run once i went from 32 to 37 in one hard run so it would either go up slow or heat fast from my experience the max i seen them heat up to was 43 when i was running 32 it was a hot hot day here.

ULLLOSE

iTrader: (1)

I had 42 psi cold in my car at natls this year.