k11 Anti roll bars???

[lee k0011]

Noticed a while back that my very basic spec micra hasn't got any anti roll bars..

So i was thinking of just fitting some O.E ones as a cheap upgrade.

I no you can get upgraded ones, but i don't wont to spend that sort of dollar on them!

Has any one els done this?? And if so did it make a big difference ???

 

[frank]

the brackets on the chassis and axle were,nt there on my blue k11 rear lee, i think the boltholes for the front one are there tho, and i removed the a/r/b,s from the red car

 

[lee k0011]

the brackets on the chassis and axle were,nt there on my blue k11 rear lee, i think the boltholes for the front one are there tho, and i removed the a/r/b,s from the red car

I can see the bolt holes for them on the front of mine. So mite just fit a front one..

Do they not make a big difference tho Frank?? As you took yours off..

 

[frank]

i dont think they are very effective personally mate, even paul,s (polly) seems to have an alarming amount of bodyroll with coilies and whitelines fitted.
my red car is very loose at the back, but the white car is very neutral (4 wheel slide in the wet) but i dont know if thats because the white one still has the rear a/r/b fitted or if its the 100kg weight difference.
personally i think that when you lower these k11,s 70mm+, and remove some of the weight, they out handle most cars anyway (irrespective of coilies or a/r/b,s)

 

[lee k0011]

Ok thanx for your help Frank..Mine is very tail happy in the wet, But as long as you keep your foot down it is pretty much impossible to spin

 

[hoopdub]

didnt realise they were an option, i thought they all had them, in that case i may well take mine off

 

[reflexuk]

A car that doesn't benefit from a pair of anti roll bars is usually riding on suspension that's over stiff. It will be usually able to find more grip when softened back up again, then the body roll comes back.

If you plan to leave the shocks standard then yes, a pair of anti roll bars will improve it's cornering capability and grip, without a compromise in ride comfort and bump handling.

Personally, I like urgency of turn feel that a firmer rear bar gives. IMHO on a typical fwd car uprated a/r bars are a better bang for buck investment than coilovers etc

Nissan fitted them as standard from 1997 on, but strangely not always!

 

[frank]

A car that doesn't benefit from a pair of anti roll bars is usually riding on suspension that's over stiff. It will be usually able to find more grip when softened back up again, then the body roll comes back.

If you plan to leave the shocks standard then yes, a pair of anti roll bars will improve it's cornering capability and grip, without a compromise in ride comfort and bump handling.
He
Personally, I like urgency of turn feel that a firmer rear bar gives. IMHO on a typical fwd car uprated a/r bars are a better bang for buck investment than coilovers etc

Nissan fitted them as standard from 1997 on, but strangely not always!

It sounds like the oz guys remove the front bar when doing khana,s tho (similar to your time trials ?) because it lifts the inside front wheel i guess

 

[reflexuk]

It sounds like the oz guys remove the front bar when doing khana,s tho (similar to your time trials ?) because it lifts the inside front wheel i guess

Ah, do they? This sounds like the typical traction loss when a fwd car rolls over heavily on its rear outside wheel. Instead of identifying and fixing the real cause of the issue the 'crutch fix' is to give the car a fully independent front in an attempt to keep the front inside wheel on the ground. It's the easier cheaper solution too. Of course, in the same corner at the same speed, the car will dive into the turn then suffer further increased body roll, the outside front tyre will mispresent to the road, overload and slide earlier than before ultimately resulting in a slower corner, at least you wont have a smoking inside front tyre and no forward motion off he corner though.

Here is a graphic example of the difference. This car has a stripped interior, is lightened as far as f1000 rules will permit, has a lower gear ratio, has competition suspension and likely cost several thousand to build. His best option is to handbrake turn and spin wheels ie 'chuck it' round the course. Notice how the car virtually stops in every turn, listen to the engine note as it spins it's front inside wheel wasting time and tyres


Compare it's style to my car which is essentially stock but has lowering springs, uprated roll bars and therefore didn't


It is possible to go too hard the result is absence of weight transfer and loss of grip but the manufactureres don't make 'em that hard. IIRC my whitelines are some 250 times harder than stock! I was shocked to discover this at the time, yet I still obviously have bodyroll. The only serious downside of uprated roll bars comes when it comes to extremely low grip or extremely bumpy ground. Anti roll bars - missunderstood and vastly undervalued.

 

[lee k0011]

Ah, do they? This sounds like the typical traction loss when a fwd car rolls over heavily on its rear outside wheel. Instead of identifying and fixing the real cause of the issue the 'crutch fix' is to give the car a fully independent front in an attempt to keep the front inside wheel on the ground. It's the easier cheaper solution too. Of course, in the same corner at the same speed, the car will dive into the turn then suffer further increased body roll, the outside front tyre will mispresent to the road, overload and slide earlier than before ultimately resulting in a slower corner, at least you wont have a smoking inside front tyre and no forward motion off he corner though.

Here is a graphic example of the difference. This car has a stripped interior, is lightened as far as f1000 rules will permit, has a lower gear ratio, has competition suspension and likely cost several thousand to build. His best option is to handbrake turn and spin wheels ie 'chuck it' round the course. Notice how the car virtually stops in every turn, listen to the engine note as it spins it's front inside wheel wasting time and tyres


Compare it's style to my car which is essentially stock but has lowering springs, uprated roll bars and therefore didn't


It is possible to go too hard the result is absence of weight transfer and loss of grip but the manufactureres don't make 'em that hard. IIRC my whitelines are some 250 times harder than stock! I was shocked to discover this at the time, yet I still obviously have bodyroll. The only serious downside of uprated roll bars comes when it comes to extremely low grip or extremely bumpy ground. Anti roll bars - missunderstood and vastly undervalued.

What shocks are you running then??? Lifting the rear wheel alot. My old 205 rally used to do that, but that was running Bilstein's

 

[1275]

IRC my whitelines are some 250 times harder than stock

do you mean 250 times stiffer? how is that acheived?

 

[reflexuk]

What shocks are you running then??? Lifting the rear wheel alot. My old 205 rally used to do that, but that was running Bilstein's

At the time it was running stock dampers with a set of lowering springs. I don't know what make they are, I bought them on the car. They are black steel, not powdercoated. The rear wheel lift isn't too much of a problem, in fact it probably helps rotate the car, until the car oversteers, which it didn't at these speeds. I did notice it seems more willing to do so in left direction than to the right, I can't be certain but I beleive it's to do with a lift force transmittted along a panhard rod design. All fwd cars should do it when pushed hard in good grip, particularly on corner entry and mid corner, they're designed to, it's so the car still has traction. Conversely Rwd cars are often seen lifting an inside front particularly on corner exit, gravel spec rally cars on tarmac and 1/4 mile oval sprint cars do it a lot, it's even visible in F1 cars sometimes.

I have now replaced the rear dampers for some uprated Fk automotive ones and the front struts for some Avo ones with adjustable rebound damping that take 2.25" id 12" long competition springs. I don't know how it would go if I were back there today, even better I would hope lol.

 

[reflexuk]

do you mean 250 times stiffer? how is that acheived?

Yes, my bad. I meant 250% stiffer, 257% to be precise. Same design thicker bar is the answer. Here's the explanation
http://www.whiteline.com.au/docs/bulletins/BL-281.pdf
The stock bars are 16mm if I'm not mistaken, mine are 22mm, It's ony 33% thicker material but due to its torsional rigidity soooo much stiffer.

Imho you could do a lot worse than fit 2 stock roll bars at each end of the car! Which is an engineering challenge more suited to minds like Franks. However, I have wondered how much stiffer they could be made by simply welding a piece of material straight across the middle section of the respective bars, effectively turning that bump in the middle of them into a rectangle, that should work too.

 

[lee k0011]

At the time it was running stock dampers with a set of lowering springs. I don't know what make they are, I bought them on the car. They are black steel, not powdercoated. The rear wheel lift isn't too much of a problem, in fact it probably helps rotate the car, until the car oversteers, which it didn't at these speeds. I did notice it seems more willing to do so in left direction than to the right, I can't be certain but I beleive it's to do with a lift force transmittted along a panhard rod design. All fwd cars should do it when pushed hard in good grip, particularly on corner entry and mid corner, they're designed to, it's so the car still has traction. Conversely Rwd cars are often seen lifting an inside front particularly on corner exit, gravel spec rally cars on tarmac and 1/4 mile oval sprint cars do it a lot, it's even visible in F1 cars sometimes.

I have now replaced the rear dampers for some uprated Fk automotive ones and the front struts for some Avo ones with adjustable rebound damping that take 2.25" id 12" long competition springs. I don't know how it would go if I were back there today, even better I would hope lol.

It looks good to have a wheel or two in the air. If all 4 wheels are on the ground, your not trying hard enough lol
Auto solos look like fun tho. They have them just up the road from me at Demontweeks a couple of times a year..

 

[reflexuk]

It looks good to have a wheel or two in the air. If all 4 wheels are on the ground, your not trying hard enough lol
Auto solos look like fun tho. They have them just up the road from me at Demontweeks a couple of times a year..

Here I am, a couple of years ago! Competing in the Knutsford MC Autosolo Demontweeks nr Wrexham 24.Jan.10. Result 2nd in class, beaten by a BL Mini! Micra then had cut front springs which seems to have reduced rear wheel lift. Car doesn't look pushed but it is on the grip limit, beleive me! 155 70 13 tyres are holding it back.

 

[lee k0011]

Here I am, a couple of years ago! Competing in the Knutsford MC Autosolo Demontweeks nr Wrexham 24.Jan.10. Result 2nd in class, beaten by a BL Mini! Micra then had cut front springs which seems to have reduced rear wheel lift. Car doesn't look pushed but it is on the grip limit, beleive me! 155 70 13 tyres are holding it back.

Been to see a few at tweeks. There is a yellow micra that is there competing every time i have been..
I think i mite have to give it a go one year. Would be a crime not to as it is on my door step!