View Full Version : To ARB or to not ARB??!!
Pistol Pete
10-05-12, 08:29 PM
So, i have been putting some miles on my Nova now. Last sunday, was a dry sunny day. Decided to hit some of my favourite back roads to see how it felt. Havent really managed to do this before.
Crikey!! Its abit lively!
Opinions needed.
Current setup is: Gaz coilovers all round. No FARB fitted. Springs (IMO) are too long on the rears. 8". Looking to get some shorter ones as the car "tips" on to the front end.
This all means on turn in the rear feels as if it wants to step out and throw me into the hedge!
Considering fitting the FARB and seeing how that feels. Do i need the blocks to fit it with an XE?
Do other XE guys run with or without the FARB?
mk1nova_rich
10-05-12, 08:33 PM
try shorter softer springs on the back first, the current front-down rake won't be helping the liveliness
Generally if you have stiff front springs, the fitment of a GM ARB will probably make bugger all difference
novasrikev
10-05-12, 08:35 PM
i would arb it i have done on all of mine
BRoadGhost
10-05-12, 08:56 PM
When you say lively do you mean generally on B roads due to the inherent uneveness of the surface [including corners] or does it feel like that on say a near perfectly level corner?
You haven't described if you go in a bit hot or accelerate at the apex & it feels that way. If you're getting turn in oversteer [which is most likely] it could just be down to how much steering angle / how quickly you're putting it on. That said I've not seen the ride heights, do you know the corner weights? Are you running a standard rack & untouched steering knuckles? What's the front & rear spring rates?
You can reduce turn in by lowering the rear / raising the front. Are you running quite a large amount of castor? Is the rear beam totally standard without an ARB?
Kill the rake on the front end, soften the rear a little at the same time and leave the front arb in the bin where it belongs unless you're planning a custom one with drop links. That should shift it towards a less lively set up.
Get the tracking checked first if you haven't already, and give it about half a degree or so of toe in to soften the steering response a touch.
Pistol Pete
10-05-12, 09:06 PM
Generally feels unstable from the rear on turn in. Not at a silly speed.
Rear is as low as possible. Rear beam has an ARB. Standard rack and knuckles. Corner weights, no idea! Front could be raised but will look silly! Spring rates are as Gaz sent. 350lb IIRC??
EDIT: MK999, just seen your reply. Tracking is bob on. My mate set it up before Castle Combe. Still feel i need some shorter springs on the rear to level the car out abit. So the ARB is a no go??!! Will try to get a side on pic.
http://img.photobucket.com/albums/v310/Pete_58/Nova/IMGP4328.jpg
Fit a front arb, then you'll have your own opinion, which is far better than someone thinking they know the answer from reading it in say a uni text book for example
Personally I think a nova is shocking without one fitted and I have tried many set ups with big and smallblock lumps
Pistol Pete
10-05-12, 09:11 PM
Do i need the lowering blocks to fit it with an XE?
You will need the blocks on a standard xe manifold
Do i need the lowering blocks to fit it with an XE?
it bolts on under the tie bars, so if there are no lowering blocks fitted, it will still fit.
i am probably going to invoke the wrath of a lot of people here, but....
over lowering a car without making significant modifications to the suspension geometry & components will wreck the handling....
and novas on the road are way better with an arb imho.....
it could be something as daft as tyre pressures, get a decent gauge & try a few different settings.
Pistol Pete
10-05-12, 09:24 PM
TBF Mowgli....opinions are what im after! Checked the tyre pressures. Again, basic prep as i did intend on venturing on track at the action day. After my outing on sunday, glad i didnt lol
for track use, i'd imagine a slight toe out would help with turn-in.
handling is such a subjective thing & personal taste is a huge part of it.
EDIT: MK999, just seen your reply. Tracking is bob on. My mate set it up before Castle Combe. Still feel i need some shorter springs on the rear to level the car out abit. So the ARB is a no go??!! Will try to get a side on pic.
ARB's are great, the problem with the Nova one is while your track control arms want to move up and inwards, or up and out depending on ride height, the arb ideally wants to torque itself up and forwards, so if it was solidly mounted (and you assume nothing bends for simplicity) your suspension would lock up. So what it actually does is restrict suspension movement and squash the bushes it's mounted in, if it slips at all it may well stick in a different position, sitting you on the piss, or at a different ride height etc.
Levelling the car out will help as currently you're basically tipping the whole car forwards, CoG moves towards the front slightly, and you end up with a car that likes to rotate around a slightly more forward position, trying to swing the back end round. Affects your longitudinal load transitioning too which will make it feel a lot more lively turning in on the brakes.
I'd fit the TCA lowering blocks anyway, it will induce a small anti dive effect, which well help keep the car more level in braking, although it may feel a little more skittish over bumpy braking zones. Generally these level each other out a bit, and a small amount of anti dive is desirable. When you get to a higher % anti dive, it starts to become a bit more track orientated.
You main balance option and first port of call on a nova though, will be the spring stiffness, altering the ratio front to back will make a big difference. It doesn't quite work in the way logic dictates, but basically softer = more grip on that end.
If you really must try a nova front ARB, at the very least polybush with it plenty of copper slip, as this will reduce how much it sticks and restricts your suspension movement. What were your tyre pressures hot?
From the pic you posted, I would either raise the front, or lower the back, try that and a front arb
novarally
10-05-12, 09:35 PM
Have you checked the cambers?
Could be something out of alignment which is exaggerating things.
I'd set the tracking to parallel, and maybe try a small amount of toe-out for track use.
ARB's are great, the problem with the Nova one is while your track control arms want to move up and inwards, or up and out depending on ride height, the arb ideally wants to torque itself up and forwards, so if it was solidly mounted (and you assume nothing bends for simplicity) your suspension would lock up. So what it actually does is restrict suspension movement and squash the bushes it's mounted in, if it slips at all it may well stick in a different position, sitting you on the piss, or at a different ride height etc.
Levelling the car out will help as currently you're basically tipping the whole car forwards, CoG moves towards the front slightly, and you end up with a car that likes to rotate around a slightly more forward position, trying to swing the back end round. Affects your longitudinal load transitioning too which will make it feel a lot more lively turning in on the brakes.
I'd fit the TCA lowering blocks anyway, it will induce a small anti dive effect, which well help keep the car more level in braking, although it may feel a little more skittish over bumpy braking zones. Generally these level each other out a bit, and a small amount of anti dive is desirable. When you get to a higher % anti dive, it starts to become a bit more track orientated.
You main balance option and first port of call on a nova though, will be the spring stiffness, altering the ratio front to back will make a big difference. It doesn't quite work in the way logic dictates, but basically softer = more grip on that end.
Not trying to be argumentative but, have you actually had a big block nova that you have drove on the road ? Opinions are far more convincing if they come from experience
Have you checked the cambers?
Could be something out of alignment which is exaggerating things.
I'd set the tracking to parallel, and maybe try a small amount of toe-out for track use.
Toe is very very subjective, but toe out will make it more lively on entry, which is what Pete is trying to avoid here. Personally I'm with you though, small amount of toe out static, and set to toe in on bump feels fantastic to me. Darts into the apex, takes a set, pulls in on the toe in on bump when the outside wheel settles, then as it rebounds just keeps it nice and steady to get back on the power. :d
Not trying to be argumentative but, have you actually had a big block nova that you have drove on the road ? Opinions are far more convincing if they come from experience
I drove a TD for ages, which is around the same weight. Personally I hated it because it felt so front heavy and sluggish to turn in, but then I like a particularly responsive lively drive personally, which is why I ended up just decking it for a laugh rather than battling with handling.
As for my experience, it comes from a different angle, a basic understanding of dynamics, and knowledge passed onto me by ex race engineers, chassis dynamicists and data analysts that have worked in F1, F2, F3, GP2, GT series, sportcars, le mans, Caterham etc etc. My personal experience with setting up specifically Novas was my 1.6 8v that I drove for 6 months or so through various set ups and tweaks.
It means I can set up more than just a Nova, and take ideas and experience from a lot more areas. I don't see why I should need to have driven a 2.0 16v Nova to apply the same knowledge I would to a car that nobody has ever driven before, or even built.
and pretty much all that knowledge from your lecturers was gained on stuff that was very basic & usually based on triumph/ford bits (lotus) or had massive downforce going thru huge slick tyres....and rwd and for professional racing drivers with cat like reflexes
setting up a front wheel drive car properly is still a black art, and lots of people still try to set them up so the back end comes round, whereas an understeering car is probably safer for most of the rest of us mere mortals
Gaz rear coilovers on lowest thread make any car drive horrible and very unstable, raise it 40 just for a test and you'll see what I mean.
Pistol Pete
11-05-12, 06:24 AM
lol I have 8 inch springs on the rear, hence why the cups are at the bottom. If I raise it 40 the front bumper will hit the floor.
BRoadGhost
11-05-12, 12:11 PM
So does it induce oversteer as you're going into a bend off / on part throttle, when you're braking into the corner and begin to turn in or at the apex / onwards on throttle?
I don't run any ARBs as the spring rates / lengths are suited to tarmac with the cars center of gravity & structural strength. I don't run any toe or anything more than about a degree of camber because of this.
Looking at the photo the back can come down more if you're prepared to do the work, because as it stands the weight balance is probably about 70% front and 30% rear.
I like mine to toe out and run mine quite low. However i have the correct speing lengths and have done modifications to the rear to compensate for that. Just my opinion.
Pistol Pete
11-05-12, 05:35 PM
What you call correct spring lengths Paul? And what modifications have you done?
Had a look at it all today. I think they are 6 inch springs on the front. Whats to stop me swapping fronts with the rears??
Can someone explain how the spring lengths make a difference?! I have 10" rear springs on my Gaz rear setup which lowers further than I want to run it.
Pete my GHA shocks are 2.25" springs front and 1.9" rear so aren't interchangeable
a long spring with the same rate as a short spring will have totally different characteristics.
And what are those different characteristics?
Gaz recommended 10-12" springs on the back of my GHAs when I was ordering them.
http://www.trackpedia.com/wiki/Suspension#Suspension_effects
Interesting link Paul, read lots of it but can't see anything that says different spring length, but same poundage, changes characteristics?
(I'm assuming the spring platform is moved to give the same ride height on the coilover if that makes a difference?)
Pistol Pete
11-05-12, 10:05 PM
So what's the recommendation for rear springs. I'm going for 6" springs, but not sure on poundage. 350lb do it?
Fit a front arb, then you'll have your own opinion, which is far better than someone thinking they know the answer from reading it in say a uni text book for example
Personally I think a nova is shocking without one fitted and I have tried many set ups with big and smallblock lumps
Aww not convinced enough by your argument to say they are dangerous without one anymore? :p
The oem bar is utter turd, a properly designed setup would be a benefit though.
Nope still think its dangerous without one :d
blue_peg_16v
12-05-12, 08:52 AM
Having driven both on a big block I'd throw it in the bin and leave it there
paul james
12-05-12, 09:00 AM
Having an anti roll bar adds more weight closer to the ground, that improves handling by itself doesn't it? (not by much I imagine, but still something and I thought I'd just throw that point into the arguement)
People whole take them off obviously like more understeer, that's all ive ever gained from removing one
mk1nova_rich
12-05-12, 09:16 AM
I removed mine on my C16XE Nova and couldnt notice the difference tbh, I actually think its a psychological thing as daft as it sounds. If someone removed your ARB without you knowing I bet 9/10 people wouldnt notice
Having an anti roll bar adds more weight closer to the ground, that improves handling by itself doesn't it? (not by much I imagine, but still something and I thought I'd just throw that point into the arguement)
Lol
I removed mine on my C16XE Nova and couldnt notice the difference tbh, I actually think its a psychological thing as daft as it sounds. If someone removed your ARB without you knowing I bet 9/10 people wouldnt notice
apart from going back to a car with door handles rubbing on the tarmac at every corner????
Without going into the motorsport related theories, i ran an xe without an arb and preferred it to with. I ran poly bushes in all suspension bushed areas. It wasn't "dangerous" imo and was good b road fun. Pete try it without if you currently have one, and try it for yourself.
It's 8 nuts and 10 mins. Fit one, try it, see if you enjoy the company of men, if not then take it off.
It's 8 nuts and 10 mins. Fit one, try it, see if you enjoy the company of men, if not then take it off.
This (lol)
It's 8 nuts and 10 mins. Fit one, try it, see if you enjoy the company of men, if not then take it off.
Does that mean you run an ARB then :p
Does that mean you run an ARB then :p
The brapmobile has one, but I drive the passat mostly now...... I think that has an Arb too lol
As I said,the oem nova Arb is toilet but a properly designed/fitted one would work like a charm
stu, i take issue with your comment..
i have the front & rear arb's fitted & at no point have they made me want to go cottageing, or suddenly think lisa minelli is good
Pistol Pete
12-05-12, 10:25 AM
It's 8 nuts and 10 mins. Fit one, try it, see if you enjoy the company of men, if not then take it off.
lol
John, the detailed motorsport questions were abit much! I will fit the arb and see what's what.
Any advances on poundage for new rear springs. Going for 6 inches.
When i first put my XE in i run without the ARB and tbh i didnt notice a difference all i had was the rear axle ARB but when i refitted it it didnt roll, dive it felt better so i left it on. But like people have said its down to personnel preference.
BRoadGhost
12-05-12, 06:35 PM
Edd I'm surprised you experienced more understeer without the front arb - I found the opposite due to it dulling the turn in.
In terms of spring lengths, the longer spring will have more travel with the same resistance as an equally rated shorter one. "Getting it right" [for this instance a tarmac car] is as long a spring as possible when the ride height is where you want it, with enough stroke to not bottom out the damper or spring and not be such a high rate it either damages the shell or causes excessive wandering at high speed.
nova_saloon
18-05-12, 03:06 PM
you need something less stiff, I opted for bilstiens on the front, as they have some comfort (i say some, More then others) but they deal with the road surface as well as cornering well. but also ive put on some quite soft dampers on the back, made all the difference, had avo's on it before, swap them for some soft cheaper ones, handled sooo much better! instead of squirming everywhere
Royston
18-05-12, 05:58 PM
If someone removed your ARB without you knowing I bet 9/10 people wouldnt notice
Your probably right, but it is noticeable, I went on a Prodrive vehicle assessment course, we drove Mazda RX8's Mondeo ST300 and Subaru STi's for front, rear and 4wd, they then messed with ARB's, tyre pressures, tyre specs, etc and we had to assess them on their test course.
Best course I've ever been on!!!!!!!!! it was £2k for 3 days:d
BRoadGhost
18-05-12, 07:17 PM
Jesus; I'ud have wanted the Mondeo to take home for that sort of money.
Pistol Pete
06-06-12, 02:14 PM
Need to resurface this...
Had a proper butchers at this earlier. If i am to refit my FARB, it will foul the exhaust manifold. Badly!
Even if i add some 20mm blocks to all 4 mounting brackets, it will still hit it.
So, how have the rest of you got your set up? Pics would be great.
Iains set up....
http://iainel.co.uk/images/forums/NovaWIP2a/613.JPG
Now i notice he has also added spacers to the underside of the tie bar mounts. Doesnt this "twist" the tie bar where it bolts to the lower arm?
I've refitted mine with an additional three M8 washers at the front (between the lowering block and top U bracket) and one M8 washer at the rear brackets. Partly to stop it deforming the bushes so much but also to give more clearance.
I don't think the tiebar lowering twists the tiebar as the lower arm is still in the same position so it can't rotate without affecting that?
Pistol Pete
06-06-12, 02:31 PM
Will have to get some alloy, make some blocks and have a play.
Worth noting it looks like its crushing the rear bush a fair amount just with that level of spacing (sits at quite an angle on the rear brackets) so I'm unsure if you could just double the size of the block on the front if you get me...
boomtings1
06-06-12, 08:13 PM
To combat the oversteer, what about trying different tyre combinations. Like some realy soft compound tyres on the rear and not so soft on the frount?
Try this site, gives peoples reviews of different tyres as to how grippy they are and so on.
http://www.tyrereviews.co.uk/Tyre/
Pistol Pete
06-06-12, 08:27 PM
*facepalm*
I am not forking out for new tyres lol
I am looking for info on other peoples suspension setups.
boomtings1
06-06-12, 08:30 PM
Ok just tryin to help, but maybe somthing to consider when you do need some tyres as they play a vital role.
Pistol Pete
06-06-12, 08:32 PM
Its a Nova, not an F1 car. I am well aware that tyres come into it, but IMO not a massive factor.
Thanks for your input.
Powered by vBulletin® Version 4.2.5 Copyright © 2025 vBulletin Solutions, Inc. All rights reserved.