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Dogo
05-07-2004, 10:42 AM
Traction when accelerating can be a b*tch in front wheel drive cars like ours. especially in the lower gears.

Recent discussions regarding choice or turbo due to traction issues has got me looking for ways to improve traction on takeoff, and get the power to the ground without having to ease off in the lower gears too much.

post your suggestions here !

I've possibly got the worst traction out of the turbo members, as I'm currently using stock v6 springs. Theres just too much movement in the suspension, but it'll be stiffer when I lower it again.

I've got aftermarket shocks in the front, but not the back. My understanding is that stiff fronts will help handling corners etc.
Am i right in presuming that stiffer rear shocks would help keep the front down during aceleration ?

another option would be to map boost curves ( for us turbo ppl only obviously ) with low, smooth boost increase in the lower gears. I plan to get an AVCR soon which would allow this.
But i'd prefer to not have to sacrifice too much power if i can

Rupewrecht
05-07-2004, 11:25 AM
for FWD cars and traction (at least in a straight line), apparently the best setup to have is

soft front
hard rear

and have the rear higher up which helps with weight transfer as it's less inclined to shift the weight of the car backwards

also depends on how much camber you are running at the front. more will help with cornering, but will give you less of a contact patch on the road which will harm your chances and increase torque steer

and when was the last time your car had a good wheel alignment?

ABC
05-07-2004, 11:29 AM
Yep, from my rudimentary understanding, to change the handling at the front you have to alter stuff at the rear.

ie. to stop the car lifting the inside rear wheel around corners you have to stiffen up the front etc.

So to help power down at the front, stiffening the springs/shocks at the rear should help. The V6 does tend to squat a bit on take off which would reduce the downward pressure on the front wheels. Then again, the V6 has the extra weight of the engine to push it down at the front - You must have terrible power down with a light 4CL in it. :?

twilightprotege
05-07-2004, 11:34 AM
stiff engine mounts helps a lot!

ABC
05-07-2004, 01:06 PM
whoa! so does that avatar!!! :shock: :shock: :shock:

twilightprotege
05-07-2004, 01:08 PM
LMAO!!!!! not bad is it??? hehehehehhe

fruitbat38
05-07-2004, 02:20 PM
It's very off topic.
It's very hypnotic.
It's very distracting.

I like. :D

fruitbat38
05-07-2004, 02:26 PM
Having good tyres helps.

Having only used 14" rims that came with the car I don't know what difference larger tyre size makes.

Would upgrading the rims make a big difference?

Does having lower profile tyres make a difference? With large sidewalls you can lower tyre pressure and have larger contact surface of front tyres. But at standard tyre pressure does the low profile have improvent over taller tyre?

lamby1986
05-07-2004, 02:49 PM
adding weight in front of the front tyres helps for traction as it stops the car leaning on its rear haunches. although you try to figure out a way to mount it :roll:
and if you did, have fun with your cornering abilities afterward, and locking a back brake when stopping quickly.

twilightprotege
05-07-2004, 06:52 PM
generally going for lower profile tyres gives you the options of stickier tyres...so yes more traction.

also, for track only, lowering the tyre psi helps as well. i think 15psi for drag racing on the fronts (anyone sure of this???)

Dogo
05-07-2004, 06:57 PM
i think if u went 15psi on low profile tyres ( eg 18s ), the sidewalls would fall to pieces !! :lol:

twilightprotege
05-07-2004, 06:59 PM
for track work only ofcourse - but even so, what about 16's?

Cosmo Dude
05-07-2004, 07:10 PM
If you look at drag slicks they are very high profile with flexable sidewalls which absorb some of the initial torque of the take off. Low profile tyres are only good to show of big 'Bling-Bling' wheels, most racing codes don't use them and the tyres they use reflect this.
The side walls of low profile tyres need to be quite rigid to survive the stress of being streached onto the rims they are designed for. And yes you can get excelent, sticky tyres (as good as low profile) in 60 or 70 profile.

Oracle_SOD
06-07-2004, 12:39 AM
also try a castor (anti lift) kit from whiteline, they are for the 4wd model but theres no reason why a FWD cant use it....

i would also recommend a better sway bar setup

BigMal
06-07-2004, 02:02 AM
Anti-Lift kit is not required on a BA I checked. The lower wishbone is actually
horizontal so there is no need for the offset bush. Replacing the bush with
Nolathane does help handling quite a bit, its cool being the Whiteline R&D car
sometimes :)

Remember that if you increase the push down at the front for taking off it will
also cause it the nose to dive on braking causing bad cornering and possible brake
lockups by forcing the front brakes to do more work than they already do 80%.

If you were dragging the answer would be a ladder bar to hold the front down
and tall tyres that would flatten out on start to increase surface contact like slicks .
Unfortunately neither are legal on the street.

Best of luck with it.

Mal

Nate
06-07-2004, 11:30 AM
less right foot??? ... as for the boost curve thingy could you do a system similar to the one the f1's use for take off now traction control is banned ... basically means the driver can plant it as had as he likes and the computer will determine the maxium accceleration without loss of traction. (up until 100km/h i think) ie work out the maxium power that can be put to the wheels without spinning em and map that thru the computer so no matter how hard you put your foot to the floor the car will only ever reach point where it is about to break traction ... i dunno just a thought ... i know this would be very expensive to set up but there has to be a happy medium or a cheaper way of doing it.

JynX
06-07-2004, 11:59 AM
Aaron and I spoke about this when we went to get the blue monster.

Similar system to the BAXR6T which will detect slippage on the drive wheels and bleed boost accordingly. Intelligent boost controller if you will.

Im sure ive seen somthing similar made by HKS or the like.

Only problem I have is that my wategate wont hold anything less the 14psi so will mean either running a bigger exhuast housing or putting in a bigger wastegate.

Aaron
06-07-2004, 02:23 PM
Why not get a little smart and implement either a "torque control" system or a basic "traction control" system.

They're not hard to do in theory thanks to the maths about desireable slip limits etc already being "out there" due to the drag racing community.

What you do need is a method of detecting throttle induced grip loss and then a way of tapering back power output. Witht he commonality of EBOVs and ETBs making a hybrid boost bleeding throttle closing system could be quite easy and not too expensive.

As Jynx says we talked about this at Dyno day and I've got a few ideas as to how to do the system 'better' than those initial ideas. The main thing you want to do is drop torque at wheels to a 'safe' level. The safe level needs to be 'determined' probably with a bit of dyno and street time. All it woudl be is a small PIC with a lookup table (500rpm steps?) that would then pulse a ETB or (probably smarter) pulse an ETB and a EBOV that is seperate to the foot controlled TB and ECU controlled EBOV

A.

BigMal
06-07-2004, 02:34 PM
I think a contact point when the shifter is in first gear to limit boost to
7psi is a much cheaper option than detecting slip in the wheels even if you
include price of new wastegate+housing+flange mods to allow a limit to 7psi.

Dogo
06-07-2004, 03:45 PM
thats actually a pretty good, simple-ish idea Mal ! :D

im thinking ill sort out my suspension first and go from there

to save me looking at ecu specs, does any1 know if many aftermarket engine mangement systems let u map boost seperately for different gears ? i know the AVCR lets you do it, but theres no point getting that if i decide to get an aftermarket ems

JynX
06-07-2004, 04:37 PM
I can map boost against rpm but not what physical gear im in.

A fixed limit is an option, but say you potentially loose traction in 2nd or even 3rd.

The system aaron describes would be a better option overall.

Rupewrecht
06-07-2004, 05:11 PM
i have a vague recollection i can have the wolf do that (gear vs just rpm) but i've never investigated it

probably because i dont get the traction problems in-gear with the bigger turbo as much as the baby one

Cosmo Dude
06-07-2004, 05:38 PM
i have a vague recollection i can have the wolf do that (gear vs just rpm) but i've never investigated it

probably because i dont get the traction problems in-gear with the bigger turbo as much as the baby one
The wolf can use either internal or external (via the plug in module) maps which can be switched via the auxilary input.

Dogo
06-07-2004, 05:45 PM
so a combination of that and Mal's contact point on the shifter, and it could swap between the different maps automagically ?!

interesting ! :)

looking at the Wolf v4 software, u also have the option of trimming the boost level using an aux input ( mapping +/- trim% based on input voltage ) . That might be useful too.

fruitbat38
06-07-2004, 06:30 PM
I like that new word " automagically" :)

I think a contact point when the shifter is in first gear to limit boost to
7psi is a much cheaper option than detecting slip in the wheels even if you
include price of new wastegate+housing+flange mods to allow a limit to 7psi.

So how much would mods cost for this? And could you save time and money if you built your turbo system like that in the first place?

BigMal
06-07-2004, 06:37 PM
Or you could simply get a turbosmart type2 boost controller and use a contact switch to
trigger the change from low to high boost. So when there is contact you get low boost
and when you shift away from 1st and there is no contact you get high boost. Price would
be less than $200 so weight that up against trying to modify your ecu. Autospeed did an
article on this years ago so I cant take credit for it :)

Mal

Cosmo Dude
06-07-2004, 06:53 PM
Added to Mals' idea you could put in an additional switch to run the car on low boost to save on fuel and reduce the chances of breakages. $200 plus a little wiring is cheep insurance.

(you could then put an override switch in the steering-wheel for 'oops it's a V8' mode) :D

twilightprotege
06-07-2004, 06:56 PM
yeah i was just thinking a switch on the steering wheel.... could be easily set up i'm sure

Cosmo Dude
06-07-2004, 07:02 PM
Other than that, don't you have a G series gearbox? Get an LSD (it's an option)

platypus
06-07-2004, 07:27 PM
i know a few of the ecu's have launch control, never looked into it , so i can't tell ya off hand.... basically it won't rev over X when say the button is pressed, or the clutch is pressed... good safe guard

Cosmo Dude
06-07-2004, 07:40 PM
Systems like the Motec M8 has launch and traction control but why not also install the quaife six speed sequential gearbox and torsen diff as well. Probably a $30k package but it would be bullet proof :oops: :roll: :twisted: and give you rocket like acceleration. :D

BigMal
06-07-2004, 07:51 PM
Ecu's that will do traction control

http://www.200sx.org/ecudata.html

Regards

Mal

RogerRamjet
06-07-2004, 08:47 PM
sorry to get off subject again but i just sat and stared at twilights avatar for like five minutes.

OMG im so sad.

Cosmo Dude
06-07-2004, 08:57 PM
It is hypnotic

OMG i'm so male

twilightprotege
06-07-2004, 08:59 PM
LOL!!!!