Haha,though to throw into a corner b4 but i was too scary...
1 mistake n my car will end up sticking to the divider/drain...
For the axle,is quite lasting for me..
It can last 3yrs(mostly daily drives)...
Im using Retread tyre for the rear most of the time,so is not too expensive for me... :D

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Ya know what, ...my money is on the welded diff for sure. Typical charateristics is understeer into corners and oversteer coming out. Do yourself a favour and swap the welded centre out for an open spinner or even better a LSD unit.

If you think that you are going to keep the welded diff & still drive it on the street then modify your driving technique to speedway style & throw that sucker into the corner & steer it with the throttle.

Keep a good supply of spare axles on hand too.
Oh yeah, what brand of tyres do you use? I want to buy shares in the company.

my rear bar is off a commodore, you dont have them in malaysia- it was heated with an oxy torch by daveman i think and bent into sape to fit. works ok, not as stiff as a proper built sway bar set up but better than none. i estimate about 70% effective compared to previous set up of no sway bar.

Rallytwit: The rear height were juz equal if equip wif frt 185/60r13 n rr 155/80r12. Other than tat,the rear will b slightly higher than frt. 155 n diff is to make drifting easier + combat understeer.

Will try ur set up soon...
But those rear bar is kinda hard to get around Malaysia..
From wat other model u guys suggest?

Whoah,kinda detail info u all posted...
Actually i used my car for drifting...(but used it for daily too)...
BTW the corner i meant is jus nice flat turn. No bumpy/holes..

Jmac: No understeer when start to turn in,but when i steer more it start to under or if i suddenly steer more(like to evade thing on the road) it will understeer hard...

For the front suspension,i really hv no idea bout the spring rate. But i recall tat is from S14 rear spring(i put in to the frt suspension).

For the tyre,185 int he front help to combat understeer slightly but still i think no enough(normal road tyre).
I tried 155 at the rear n help a bit to reduce understeer.

-2.5deg camber still not enough??(nvr think bout tat b4)

Agree wif u bout the toe-in stuff..

My tires r still fine. Nvr use it on track yet..

thats similar to my understanding rally twit, just wasnt sure how to explain it- im running a set up similar to what rally twit said, but using coilover front suspension and 240z cheap gas shocks and a rear sway bar- its pretty balanced for what it is.

but im using 165 65 13 rear and 155 70 13 fronts. 165 all round or even 175 on the rear would be ok too as the 155 up front tend to lock easily

Ronald lets make sure I have this right.

The ride height in the rear is lower. You have 155mm wide tires on the back but a welded diff for traction??

Also the tall rear tires (80 series) are going to have a softer / more flex in the side wall.............read softer rear suspension.

Lower rear ride height means weight transfered off the front tires

So you have the triple whammy going on: softer rear suspension / Rearward weight bias / Welded diff.................not surprised your fighting understeer.

I would ask what drove you to this set-up: did you fit the wide fronts after welding the diff to combat understeer? Then Skinny Rear tires in a further effort to combat the understeer?

If your car isn't belting out more than 85-90 Flywheel horsepower ditch the welded diff run an open diff till you can source an LSD.

I'll share with you the budget set up we started with: 185/60-13 Yokohama A008R tires, 7/8th (21mm) front bar, (15mm) 5/8 inch rear bar , cut down 240Z springs front with lower blocks rear dropping the whole car 50mm (2 inches), Cheap gas struts front and KYB shocks rear. The motor was near stock the first year we raced it but the car handled very well.............not as good as the current proper suspension but good enough.

I'd be willing to be getting the ride height equal front to back and four of the same size tires (even with the welded diff) would result in better lap times then the current set up. Don't know what kind of circuit your racing on but I also suspect with an open diff what you gain in corner speed would more than make up for the bite the welded diff offers in slow corners.

Tom

I definitely think the locked diff is a big factor there, but I have to ask a question. I'm not sure if I am reading it right. Did the car handle and turn into the corners very well and then slowly started to get worse, or did it start understeering suddenly after a part change (spring, shock, whatever)..

It's pretty difficult to know what to suggest without knowing a little bit more. Do you happen to know the front spring rate (being a mcpherson strut, the wheel rate and spring rate are close enough to be considered the same). Going too stiff will increase understeer but if it is too soft, going stiffer can help. I'd suggest that if the front spring rate was under 150lb/in then you could safely run stiffer.

It might also be that the shocks (original fronts with new oil) have started to get 'sticky' (I wish I could think of a better word) - and they aren't allowing enough movement, and it's making the front easy to slip on initial turn in. Maybe it has slightly blocked/restricted some of the valving on the shocker. Maybe try emptying them and replacing with thinner oil as an experiment (it might end up being too soft then, but it's worth a try).

Very generally you can do a couple of things to help intial turn in understeering. Of course the 'good old' option is to run more negative camber on the front wheels. I think it would be quite hard to get too much front neg camber - there just isn't enough room to move the strut top inwards (unless you run a longer control arm).

The other thing that works, but I have to warn you, it will wear out the front inside edge of the tyres if you run it on the street or very long distances. But the trick is to adjust the front toe-in - you adjust it to provide anywhere from 1-3mm of toe OUT. This typically helps initial turn in but it isn't as good for long distances, and can be a little less stable/smooth at high speeds (compared to 1-2mm of toe-in

About the only other thing I can think of (for now) that might be a factor - is there any chance the front tyres have 'gone off' - this can happen if they are massively overheated during races - even if there is a lot of tread left. Another possible cause would be if they got a lot of oil contamination or something.

Thanks again for those replies...

Unfamiliar : I dont really get why wider rear tyre with lock differential will understeer less when i use 15580 tyre...
Can u describe how?
BTW my rear is lower the front d,if i lowered it summore i think it wont look nice... :D
TQ...

As for the lock diff,i need it for track use... :)
Im trying to make my car understeer less but remain lock diff...

I used a welded diff with the 1200 GT5 car (picture avi). Car handled very well on the race track. Never drove on road. The welded diff required a "throw it in there" type of steering, throttle, brake style. If I tried to drive smoothly into a corner it would understeer quite a lot. If I drove like I was a bit "mad" at it things went much better. Biggest thing that I did chassis-wise was to free up the leaf springs as much as I could and install an adjustable panhard bar to allow for adjustment of the rear roll center as track conditions varied.

I agree that the wwelded diff is probably causing the majority of the problem.