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[feeutfo]

As with most things in life, finding the best compromise wins. Lower/wider across the width of the car improves things up to a point, even with the comparatively slight negative of incorrect wishbone position. (Too low and too wide mean the benefits get over reached obviousy.) dampers and spring rates can be achieved regardless of ride hight, but why loose the oppertunity to effectively widen the foot print v the centre if gravity of the car...? (without going too far of course)

What I find rather idiotic, is lowering for the sake of it and nothing else, by fitting crap suspension, spring cutting etc, purely because it's lower above all else. I once encountered a hill man imp looking project travelling up the m40 at an exceptionally slow 50to 60...in the middle lane I might add.
 Spotting it had no suspension travel what so ever, I hung around to see it pass over a particularly wumpy section. I kid you not the bloody thing took off and the driver very nearly lost control, also because his baseball hat fell over his eyes... Obviously a trainee idiot, as the qualified idiots where their baseball hats backwards, I guess for that very reason.

[Kevin Wood]

As said, the first parameter that goes into the design calcs for how the suspension behaves is the ride height. Change that and you've bu66ered everything else the manufacturer has designed into the suspension at a stroke.

It's not impossible that you end up with something that you believe is better, but it'll be luck of the draw.

Lowering to an insane level should be banned, and the perpetrators taken out of their cars and shot on sight. I've seen cars running around where the negative camber must have been in double figures, yet apparently someone must have given them an MOT?

[Marks DTM Calib]

Trouble is that lowering does not give you the benefit you would think.

I seem to recall some rule of thumb around the ratio of ride height to distance between the vehicle centre line and centre of tyre.

Given the Omega's size your in the relms of low single figure percentages (assuming say 900m between centre line and a 30mm drop).

Most manufacturers only lower certain models for marketing purposes, and you would not want to lower to touring car levels or you would scrape the bottom everywhere.

Clearly most uprated springs also lower the vehicle but again, this is most likely down to market trends. 

[bootie]

Right, this is slightly off topic but, there is a possibility that my rig will have a contract in Oz next year.
If that is the case (we should know by the end of this month) I could possibly bring back some of the aforementioned Kmac poly's for the rear.
Of course I would have to work out how I would get them picked up but that's just details.
No cost for transporting them back to the UK as it will all be paid for via my hold or hand bags on the flights, however, I only visit the UK once every 2 months.......
Still it's a possibility, the other thing is I have a very good mate of mine from our services days that works over there and lives in Perth WA, I'm sure he could help out as well if need be.
If, and it's a big IF, it was all easily do-able, what sort of numbers would I be looking at?

As they are for personal use and I would be hand carrying, there would be no import duty or shipping charge, does that make them a bit more respectable price wise?

Just a thought or two.

Jon

[HockeyDave55]

I have long suspected that the Catera had a softer setup than ours so some of the above may well not be as relevant.

This is highlighted very much by the Omegas tendancy not to over steer (unless US tyres are not good?) as it tends to be very controllable.

Also not that convinced by the lowering, I often preach that most of the gains found with lowering are more down to different spring and damper rates rather than it actualy being lower to the ground. This makes some sense when you think what lowering does to the dynamic geo (as the wishbone will be at a different angle in the static position). Lowering for me is more because people like the look than giving real gains.

Sure, it is very true that many people do lower their cars to make the look better and there are some that believe the doing so will improve handling and road holding, this is a sticking point for many "boy racers" that have the lowest, stiffest set-up possible and wonder why their skateboard has just spat them off the local B-road. While a set-up like they have is more suited to a race track, they are no good on most of the roads we have in the UK...
I have droped my car but it's only very slightly lower than the police set-up and yes... I did it to some degree because I like the lower look, a firm ride and just because I wanted to.... So there...

However, I just wanted to make a point that one, if not the main reason race cars are lower is that it brings the CofG closer to the ground thus reducing body roll.
Sure, you can fit huge anti-roll bars but that adds weight among other thing...

The main point is, in order to get what you want from your set-up, you need to understand what you're doing and why.... IMO of course... ;-)

[HockeyDave55]

Trouble is that lowering does not give you the benefit you would think.

I seem to recall some rule of thumb around the ratio of ride height to distance between the vehicle centre line and centre of tyre.

Given the Omega's size your in the relms of low single figure percentages (assuming say 900m between centre line and a 30mm drop).

Most manufacturers only lower certain models for marketing purposes, and you would not want to lower to touring car levels or you would scrape the bottom everywhere.

Clearly most uprated springs also lower the vehicle but again, this is most likely down to market trends. 

There are many very books on suspension geo and believe me.... There is no simple rule of thumb applied to this subject.
Like I just said ^^^^^ I have lowered my car mostly for how it looks but it's not dragging it's diff about and it's firm but not so hard it shakes my teeth out.

I don't go racing about, I drive quick from time to time but not haring about like a 17yo in a slammed Corsa!!! Lol...
I just like my ride and it's as simple as that....

[feeutfo]

Lowering. Not that simple a description. A world of deminishing returns clearly. Mv6 lsc being a prime example, as I doubt anyone would deny it handles better. Firmness of the springs and body roll aside, 15 mill drop from standard gives a lower Center of gravity. Granted the roll centre is lower too, which is bad in relation to suspension pivot points. I see it as two steps forward(c of g and spread of the load through the width of the axle) and one step back( loss of roll centre position) but only up to an arguable max of 30mill. Beyond that it all goes to 'dangle berries'.

But add it up and that's still one step ahead. I don't buy the marketing story with the mv6 either. As always, all things are relative and life us full of compromise... Obviously all that has a small window to operate in. A 30 mill window I'd say.

[razzo]

Does anybody know why they don't make the rear bush???

don't think you can buy them off the shelf but they can be made up, i did it so it can't be that difficult. Was advised that poly bushes at the rear of the wishbone would cause alot of vibration, but ran the idea past Tony at WIM & he failed to see why that would be the case so i made them & fitted them about 18 months ago & no probs 

[feeutfo]

Although I would add, 30 mill is too much when fully loaded.

[HockeyDave55]

Does anybody know why they don't make the rear bush???

don't think you can buy them off the shelf but they can be made up, i did it so it can't be that difficult. Was advised that poly bushes at the rear of the wishbone would cause alot of vibration, but ran the idea past Tony at WIM & he failed to see why that would be the case so i made them & fitted them about 18 months ago & no probs 

I'm liking that! Do you have the dims???

[HockeyDave55]

Although I would add, 30 mill is too much when fully loaded.

Would that be 30 mill for an MV6 or an Elite??? ;-)

[feeutfo]

Right, this is slightly off topic but, there is a possibility that my rig will have a contract in Oz next year.
If that is the case (we should know by the end of this month) I could possibly bring back some of the aforementioned Kmac poly's for the rear.
Of course I would have to work out how I would get them picked up but that's just details.
No cost for transporting them back to the UK as it will all be paid for via my hold or hand bags on the flights, however, I only visit the UK once every 2 months.......
Still it's a possibility, the other thing is I have a very good mate of mine from our services days that works over there and lives in Perth WA, I'm sure he could help out as well if need be.
If, and it's a big IF, it was all easily do-able, what sort of numbers would I be looking at?

As they are for personal use and I would be hand carrying, there would be no import duty or shipping charge, does that make them a bit more respectable price wise?

Just a thought or two.

Jon

a welcome thought. Are you happy to work out cost/conversion prices...? Would be most grateful if you are. These group efforts can be a real pita though.

[Marks DTM Calib]

Heres one though, your all commenting on the centre oif gravity but, for all we know it may already be pretty low.

I would suspect that if you could get a setup with the same characteristics in standard and say 30mm lower that you would struggle to feel the difference.

And on the track cars, THE major reason they lower is so the front splitter set 'works'.....its more driven by aerodynamics. 

Classic example is rally cars..........

[feeutfo]

....which they need for suspension travel over bumps. Large bumps.


___|___ is better than   __|__   Although  _________|__________  is just plane daft

I can't show a differance ride height (= | ) with a key board, but relatively the equation is the same.

[feeutfo]

                C of g
                    |
Left _______    _______ right