Alfa Romeo Forum banner

1 - 20 of 105 Posts

·
Registered
Joined
·
110 Posts
Discussion Starter #1
Hi all, I recently bought a 3.2 V6 GT which I love (too many previous Alfas to list but last one was a 3.0 litre GTV). My new GT had a Quaife Diff supplied by Autolusso fitted in 2013.

I have a problem where under acceleration when in a straight line the car pulls to the right (slight nose dive right) and then back left as if it is correcting itself when lifting off. Its certainly not a massive movement to make it dangerous but definitely noticeable and more than annoying. Round longer bends on motorways if suddenly accelerating the movement does unsettle the car.

I tried a another test where I went up to 70 MPH on a straight part of the motorway and put my foot on the clutch whilst in 4th gear and 'coasted' brieflly. The car drove straight as an arrow, no pulling left or right and felt completely solid and straight.

Soon as I lifted my foot off the clutch with 5th gear engaged, definite pull to the right again. I feel this is definitely diff related. The car has recently been serviced, been fully laser aligned, new front tyres and front suspension all sorted (through Alfa) and pulls round corners like on rails....its only when the accelerator is pressed down hard. Anyone ever experienced this and know what the issue could be??

HELP!!!!!
 

·
Registered
Joined
·
5,266 Posts
I've never had an LSD but what you are describing is torque steer which can be caused by front wheel drive cars having unequal length drive shafts (loads of discussion on that point as well!). It can also be caused by a host of other suspension related problems - but the diff is the least likely thing to be causing the problem.
 

·
Registered
Joined
·
2,757 Posts
I can't see how it would be the Diff...if the fitting was incorrect for example then it would be obvious all the time..

when were the front wishbones last done? maybe you have some worn bushes that are causing the problem under load..? BTW I have a quaife in my car which is also on Bilstien suspension and eibach ARB's and there is no pull to either side on heavy acceleration..and this is a re-mapped 1.9 so bags of torque...But before my front wishbones were done (the old ones were well on the way) the car did pull to the right under very heavy acceleration.

it is worth mentioning the stock GT suspension is very poor and roly poly, alright if you intend to pootle around. but if you want to really enjoy that gorgeous Busso then up rating the suspension is vital IMO.
 

·
Registered
Joined
·
110 Posts
Discussion Starter #4
Thanks guys. Just to clarify I've only just bought the GT 3.2 (1 week ago) traded in for my GTV 3.0 litre. The pulling to the right has been there from last week and for all I know could have been since the diff was fitted.... or possibly not! Its definitely not torque steer as I mentioned the last test I did wasn't actually accelerating but just coasting at 70 MPH and then lifting foot off the clutch which gave me the same symptom. Think torque steer is only under acceleration?

The car already had the Bilstein/Eibachs set up when I bought it...one of the reasons why I bought it (along with the Quaife diff and Stainless exhaust!!!!!). Both wishbones were replaced yesterday morning when I took it for a service and yes they were definitely shot and it has improved things but the pulling right is still there.

The issue is only under heavy acceleration and taking my foot off the clutch when coasting (as a test). If I'm driving with foot on a constant accelerator speed and turn round a corner hard or trying to unsettle the car by turning the wheel left and right quickly she handles perfectly. Its only when the 'drive' seems to kick in. Really confused!!!!
 

·
Registered
Joined
·
4,336 Posts
It sounds exactly like my GT. Boot the throttle to overtake and it pulls to the right. Slap power down on a corner, and while it will tighten, it does get a bit unsettled. Only problem is that my GT has a standard open diff. My 156 has a Quaife, and the behaviour is totally different - you can apply power mid corner, all it does is hold the road and the only limiting factor is my ability to stay in the drivers seat.

Not sure about the 70 mph coasting test. I assume you are driving along under power (i.e. maintaining 70), then dipping the clutch, and letting power back in. Never done that, but it is a variant of "applying power".

You say the quaife was fitted by Autolusso in 2013 - was the car yours then? If not, are you sure that the quaife has not been unfitted some time afterwards?
 

·
Registered
Joined
·
3,126 Posts
Sounds like a suspension problem to me. I have a GT 3.2 fitted with a Q2 diff (the forerunner to yours I believe) and don't have this issue. If you really go for it, there is a tiny amount of torque steer but that's it. I know the upper wishbones can cause some very odd effects if they are worn. Do you have any creaking noises at all? Also have you checked your tyre pressures?
 

·
Registered
Joined
·
2,270 Posts
You might well have just been spoilt by the excellent feedback to the steering wheel you used to get from your gtv. It's a difficult step back from a gtv fancy diff or not.
 

·
Registered
Joined
·
110 Posts
Discussion Starter #10
The quaife diff wasn't fitted by Autolusso just supplied by them.

Ok thanks a lot all for your replies. I get the general feedback from everyone (and RXE saying that his GT with standard diff has the same problem) suggests to me that this is more likely to be a suspension issue. I will get everything checked again and keep you posted!

Thanks all.
 

·
Registered
Joined
·
158 Posts
What about worn engine or gearbox mounts?

Not sure if that is a common problem on AR's but obviously the engine and gearbox will try and move when power is applied and removed, especially in extreme circumstances.
 

·
Registered
Joined
·
30,126 Posts
Ours used to dart about under hard acceleration on all but the smoothest roads.

Torque steer. The Quaife or Q2 helps but it's all the torque & power through two driven wheels without any flash suspension joints that causes the issues.

Great fun when you're in the mood but one of the many reasons I prefer the Q4 V6 Brera for 99% of the time.
 

·
Registered
Joined
·
3,023 Posts
Torque steer. The Quaife or Q2 helps but it's all the torque & power through two driven wheels without any flash suspension joints that causes the issue.
As I understood it, torque biasing LSDs like the Quaife actually make torque steer worse...

One wheel has more drive (higher torsional stiffness in the asymetric drive shaft), hence the diff loads up the torque on that side..

Would make sense as the nearside driveshaft is shorter, hence would get loaded up quicker by the drivetrain and push the car out towards the right...

LSDs help you manage getting the power down in the corner by allowing you to maintain traction whilst turning the steering wheel... But in a straight line they'll make torque steer worse...
 

·
Registered
Joined
·
2,617 Posts
Last time I had that problem, one of the front struts was stuffed and had lost rebound damping - put your foot down and the thing would change lanes. New struts and all sorted. Could be a really bad wishbone bush as well I guess.
 

·
Registered
Joined
·
2,757 Posts
Not my experience. Torque steer was greatly reduced compared to original, once I had my Quaife installed.

I agree...I think this is a suspension geometry thing or a worn bush. My car does not torque steer at all, it still tramlines form time to time on heavily grooved roads but on a flat road in a straight line , none. My old JTS 2.0 in comparison with 35 less ponies (if the figures are to be believed) did torque steer quite badly, Especially in a straight line on full throttle.

my money is on misalignment and or a bad wishbone bush (upper) on the offside. get the alignment re-checked and visually inspect the wishbone bushes..if you have OE upper wishbones you ca poly bush them rather than replace,significantly reduces the cost of the job and they never have to be done again.
 

·
Vendor
Joined
·
45,462 Posts
After I read your post, I'm thinking poor alignment or a knackered shock.

A 156 diesel I've bought recently pulls right on acceleration and darts left on braking, and I think I can see a bit of oil on one of the front shocks, need to get it on the ramp for a proper look.
 

·
Registered
Joined
·
3,885 Posts
Not my experience. Torque steer was greatly reduced compared to original, once I had my Quaife installed.
Same here, I do like to boot it now and again (Italian Tune up!) and I found the torque steer is still there after the Quiafe was fitted but nowhere near as bad as before when it would try and stick me in a hedge.
 

·
Registered
Joined
·
2,259 Posts
I know it might be of the diff track/suspension, but my 147 did this and some of it was down to the stability control and a sticking rear caliper.
 

·
Registered
Joined
·
203 Posts
To confirm, it's not the quaife causing this. When i bought my gta, i had original suspension, no quaife, old arms, and the car, on heavy boot was all over the place, most in 2 gear.
After quaife, new arms, suspension, arb's and so on, i don't have any of that behavior...
Like all stated above, it's a suspension issue.
 
1 - 20 of 105 Posts
Top