Alfa Romeo Forum banner

1 - 20 of 24 Posts

·
Registered
Joined
·
66 Posts
Discussion Starter #1
I know there are many threads on handling and set up, but my question is slightly different.

I have the 916 3.0l. It has Koni yellow sport shocks all round, PowerFlexed rear complete, Q2, Alfaholics handling kit and sticky tyres.

Yesterday I made two adjustments that (unless I am going completely mad) seem to me to make turn in less positive or less sharp. Firstly, I increased the negative camber slightly on the front wheels, to about - 1° 20'either side (it was already that on one side but not on the other). Secondly, I dropped the rear Konis and adjusted them from the softest setting to the medium setting.

Now my GTV feels slightly more reluctant to turn in, it's almost as if I have to put on more lock to get it to tuck the nose into the corner properly. It's not a massive difference, but I can feel it. Yet I was told by someone from a well-known UK Alfa specialist that stiffening up the rear would improve body control and get better results.

What does everyone think? Does this make sense? How is this explained?

Thanks in advance

CRAIG
 

·
Registered
Joined
·
566 Posts
Much easier to see what's happening if you change one thing (or one end of the car) at a time!

Stiffening the rear might reduce the rear-steer effect a little maybe.

How did you go about adjusting the camber, do you have adjustable top mounts?
 

·
Registered
Joined
·
66 Posts
Discussion Starter #3
I hear you on adjusting one thing at a time.
The operator at first thought that he could not adjust camber but found the adjustment bolt in the end.
Some 916s dont have camber adjustment up front?

C
 

·
Registered
Joined
·
2,084 Posts

·
Registered
Joined
·
566 Posts
There's no camber adjustment as standard that I'm aware of.. Some coilovers have elongated holes at the hub mount where they can be adjusted, but the konis I have don't seem to have this!
Of course it can be adjusted very slightly due to play at the holes but not much..
 

·
Registered
Joined
·
3,816 Posts
I know there are many threads on handling and set up, but my question is slightly different.

I have the 916 3.0l. It has Koni yellow sport shocks all round, PowerFlexed rear complete, Q2, Alfaholics handling kit and sticky tyres.

Yesterday I made two adjustments that (unless I am going completely mad) seem to me to make turn in less positive or less sharp. Firstly, I increased the negative camber slightly on the front wheels, to about - 1° 20'either side (it was already that on one side but not on the other). Secondly, I dropped the rear Konis and adjusted them from the softest setting to the medium setting.

Now my GTV feels slightly more reluctant to turn in, it's almost as if I have to put on more lock to get it to tuck the nose into the corner properly. It's not a massive difference, but I can feel it. Yet I was told by someone from a well-known UK Alfa specialist that stiffening up the rear would improve body control and get better results.

What does everyone think? Does this make sense? How is this explained?

Thanks in advance

CRAIG
If you drop the rear, you change the castor angle, thus changing the steering geometry. Only a thought.
 

·
Registered
Joined
·
566 Posts
That's something to consider for sure, but I think in his case he hasn't changed the ride height, just increased the damper settings (rebound damping).

In theory, the slower rebound would have an effect on the ride height through the bends though..

Koni actually recommend using the softest setting by default, unless the firm settings are specifically required. I'll be installing mine soon and plan to use the softest settings.
 

·
Registered
Joined
·
566 Posts
If you raise or drop the ride height at the rear (and leave the front alone) surely you change the angle the steering axis makes with the road, and thus castor, no? Though I think perhaps it's off topic from what the OP is seeing.

Camber of course being another - and indeed related - matter.
 

·
Registered
Joined
·
2,674 Posts
If you raise or drop the ride height at the rear (and leave the front alone) surely you change the angle the steering axis makes with the road, and thus castor, no? Though I think perhaps it's off topic from what the OP is seeing.

Camber of course being another - and indeed related - matter.
Prob too involved for me to answer correctly.........but why would anyone, especially on a GTV, lower only the rear!?

Clive
 

·
Registered
Joined
·
566 Posts
The OP has not done any lowering that I can see. I think the confusion stems from the 1st post where OP mentions he "dropped the rear Konis". I understand this as meaning that he simply removed them (in order to make the rebound adjustments).

However, it seems to have been interpreted that an alteration to ride height was made.

I'm just saying that that Sizewell's point - that changing ride height at one end effects castor angle - seems technically correct. Changing ride height at one end of the car changes the overall rake angle. This will give a corresponding change in castor angle.

But this is all quite theoretical, and not much help to the OP..!
 

·
Registered
Joined
·
1,138 Posts
Prob too involved for me to answer correctly.........but why would anyone, especially on a GTV, lower only the rear!?

Clive
Well......people do, I don't know why but people do. I'm overhauling a V6 that had rear eibachs with standard front springs. It also had a TS front anti roll bar fitted instead of a V6. The rear ARB was a standard V6 but had very strange mini ARB links i.e. very small ARB links. The whole setup was completely non-standard - it is now being returned to 'normal' (my normal = eibachs all round with konis).

Must say though that the handling seemed very good in the limited time I drove it. Only drove it for a week before I started the refurb but it was like a rollerskate around the bends. I understand the theory of a thicker ARB (i.e. TS) giving more understeer but I cannot say that I witnessed this.
 

·
Registered
Joined
·
2,674 Posts
My understanding was he lowered only the back. Surely this would modify the castor angle at the front, if the front remained at original height?
He didn't lower the back, he 'dropped' the rear shocks out to change their setting.

Clive
 

·
Registered
Joined
·
66 Posts
Discussion Starter #15
Gracious me. Sorry all. OP here.

You guys are right, I didnt drop the back. I had the back shocks taken out so that I could put them on the stiffer medium setting and then put back in.
The vehicle is on standard springs with no adjustment to ride height.
The only changes I made was a slight increase in negative camber, and the rear Yellow Konis set to medium. I had heard that for max reduction of understeer in a fwd, you want the rear as stiff as you can possibly go, that was the motivator. I do regular track days and only drive the car on the roads about once a week.

Sorry about all the confusion!

CRAIG
 

·
Registered
Joined
·
637 Posts
Craig,

After all that fiddling around with the front and rear did you have proper 4 wheel alignment done? Possibly the toe of the front end has changed with all the adjustments and could cause a change in the handling.
 

·
Registered
Joined
·
1,410 Posts
How about the front hide hight. It's quite normal that the front springs slags over time, and the V6 engine and transmission is quite heavy.
Have you checked the front ride hight is with in a close limit to original (new) hight?
 

·
Registered
Joined
·
2,674 Posts
Craig,

How did you increase the rear neg camber......top swivel slotted holes?

You've actually altered 3 things at once; fr camber(not normally poss), rear camber & rear shock rate.

Perahps you should undo 2 of them & see what happens, then re do the other 2 seperately?

I'd soften the rear again as that's probably the thing to make the most easily noticeable difference rather than a couple of degrees of camber.

Clive
 

·
Registered
Joined
·
66 Posts
Discussion Starter #20
Clive, once again I have confused everyone.

Checked alignment and no adjustments were made (everythign was within spec) except the front camber, which was slightly out. It seems on my vehicle you can adjust front camber slightly. I dont know if this is a conversion that someone did or what.

The second thing was to firm up the rear shocks.

As you suggest, I will change the rear shock setting back to softest setting and take it from there.

Thanks all
CRAIG
 
1 - 20 of 24 Posts
Top