Wiggle under power

[Aharmsworth]

Hi, I dont think this is norma, has anyone else had experience with a slight change of direction when changing gear when pushing hard, still getting used to the car, however when I accelerated WOT, changed gear and back to WOT, the car pulled left while off the throttle, feeling a little loose. I suspected the coffin arms or engine mounts but I am sure I am not the first to have this so would appreciate a pointer in the right direction and how to diagnose. Thanks! Andrew

 

[NXI20]

1) Toe links have worn bushes or the eccentric bolt isn't holding - they should be changed after 2 or 3 geos because they stretch & lose clamping force at the specified torque.
2) Rear diagonal arms have worn bushes or coffin arm diagonal bushes are breaking up
3) Thrust angle isn't exactly 0 degrees; when was the geo last done?
4) Tyres - had this behavior once with a set of Michelins. Swapped to a differnt set of wheels & it was gone.

 

[Roro]

Road surface has an impact too of course, I assume the road was perfectly flat without any camber etc

 

[MaxA]

I'd start with tyres (age, condition and pressure) and then the alignment. You can also have a look at the easy stuff like engine mounts.

 

[spinnaker]

I'd say engine mounts, I used to feel a bit of a shimmy at speed when changing gear aggressively on the motorway and that was the prompt for me to get some new OEM mounts fitted. Not felt it since then.

 

[Aharmsworth]

Thanks, so did some digging today and I have some play in the front wheels between 3 and 9, suspension looks original so I think I will refresh each corner, coffin arms diagonals top mounts, figure it best to do the lot bar the Dampers as that’s mucho ££.

I will then need to get the alignment done. This is where the next question comes in, can I take it down to my local tyre shop with laser alignment for caster, trail, toe or do in need to go to a specialist or my local steeler for that geo. For those of us in the uk I was thinking kwik fit with the hunter hawkeye set up? I think they offer a pay once for the life of the car service.. thanks…

 

[spinnaker]

Centre Gravity are the go to guys for people down south but there is a guy in Huddersfield somewhere who also seems to be well recommended for alignment. These are specialised beasts and if you want it adjusting correctly I'd suspect it might need someone better than the work experience kid at Kwik Fit imho.

 

[mavster]

Get the car aligned. That will sort or tell you the issue. Go to a porsche specialist that can do the job or go center Gravity for the problem cars to be sorted!

 

[Aharmsworth]

Thanks all, I have ordered a suspension re-fresh kit from spider performance

Porsche 997 C2 & C2S Gen1/2 Full Suspension Refresh Withouth Shock Absorbers Porsche Car Parts - Spyder Performance

Porsche 997 C2 & C2S Gen1/2 Full Suspension Refresh Withouth Shock Absorbers - Spyder Performance

www.spyderperformance.co.uk

That should sort out any perished rubber, intend to fit this myself as while I hate working under the car I can brush off and paint any corroded parts while it’s up in the air. Picks to follow.

Taking your collective advise to go to a specialist to have it aligned, I have 2 near me, Cameron sports cars and Porsche mode I would like to keep it local as good as COfG sound, does anyone have any experience with them? I have my clutch booked for Cameron in jan anyway..

Used Porsche Sales / Service / Storage - Used Porsche 911, 993, 996, 997, Boxster, Cayman, Cameron Sports Cars

Cameron Sports Cars Specialising in Porsche Cars based near Bath - Used Porsche Sales / Service / Storage

www.cameronsportscars.com

Bristol Porsche Specialist Garage | Porschemode Bristol

Leading independent Porsche specialist in Bristol offering servicing, restoration, tuning and bodywork for classic and modern cars.

www.porschemode.com

Thanks

 

[Roro]

You won’t go wrong with CofG. I’ve been taking my GT3 there pretty much every year since 2010 for chassis checks, alignment tweaks, advice etc and it’s 4 hour round trip for me (if there’s no traffic). Personally I wouldn’t waste time going anywhere else if I was in your situation, but everyone’s circumstances are different

 

[nodstar]

I recently had something similar, hard acceleration in 2nd and then when you come off of the throttle the rear felt like it was pulling towards the nearside, similar feeling to a cross wind.

With mine it turned out to be the offside rear damper leaking, I am not running stock dampers but thought it worth mentioning.

 

[911UK]

I recently had something similar, hard acceleration in 2nd and then when you come off of the throttle the rear felt like it was pulling towards the nearside, similar feeling to a cross wind.

With mine it turned out to be the offside rear damper leaking, I am not running stock dampers but thought it worth mentioning.

A very valid point whilst there are some simple usual suspects. The reality is there are a whole variety of factors and in my experience if it’s not the wheels or tyres it’s going to be the suspension.

When you get underneath and start taking the suspension apart, you could be shocked to find how age is a major factor in the deterioration of suspension components, not necessarily the shocks or springs, as there’s a lot more that is susceptible to wear.

 

[Aharmsworth]

So over the last few weekends, I have been working my way around each corner. It was not a super easy diy job and I have hit a couple of super seized parts. The esentric nuts were surprisingly not the worst. The hardest part was the pinch bolts holding on the front shocks on the wheel hub. The right had side I managed with an air chisel and heat, left hand side I had to cut out with an angle grinder. Time wise about 4 hours a corner, would be 2 without problem bolts.

In short if it’s not possible without some less common tools, air chisel, angle grinder, breaker bar, mag torch and an extensive socket set. While not strictly nessacery getting the car high on 4x stands and the breaks out the way helps.

Dropped it off on Saturday for a full l alignment and the clutch replacement , I must say the short drive to the garage showed even more stability issues, I would not have wanted to drive it hard. So new rubber suspension aside, alignment is super important. Hope to get the car back at the end of the week, so more feedback to come.