Floating Front End

[MikMak]

After some advice please, my 997.1 C2 cab is floating and wandering on the front end, I certainly cant stay in the fast lane on the motor way due to the floating effect and movement of the car.

I have taken the car in to a sports car specialist (not Porsche specific) for a minor service and asked they check for any wear on components etc. they have stated all seems tight and fine, and wheel alignment is also good which indicates no bush wear, apparently. ( I also now dont have a working chrono clock on top of the dash also, not related but also annoying.)

What would be the possible cause of this floating effect at speed, the car is fitted with factory PASM so I’m surprised its not and doesn’t feel planted, Im based on the Fylde Coast, is there anywhere local or within Lancashire who is familiar that could confirm what the cause is, and possibly rectify, or is it a relatively easy DIY fix.

 

[FZP]

A wheel alignment will see that disappear. Unique is probably your nearest 911 specialist at Westhaughton.

 

[plavix]

This and related questions are asked quite frequently; https://911uk.com/threads/body-wobble-with-quick-direction-changes.125753/ being the most recent. Read that for tips.

First of all check your tyre pressures, all round. Also check your tyre age, tread and make. I have a preference for N-rated Michelin, and have done for 12 years ownership of my car. Also, fill the fuel tank up.

Any car specialist will be able to identify if something is broken. so you can likely rule that out. This however is not the entire story with the 911, as it's an unusually balanced vehicle, mine is 59% rear, 41% front. Therefore under acceleration, the front will naturally be less loaded.

If tyre pressures and inspection don't work, I would highly recommend a visit to a suspension specialist, especially to Center Gravity as the team of Pete, Chris and Holly is fantastic. I've had geometry from them twice in my ownership; although my car has never felt floaty it has felt less planted prior to geometry. After minor adjustment from Pete or Chris it has been back to planted with a very pointy front-end.

 

[spinnaker]

I would suggest that a good Hunter tracking session might be a good starting point. Make sure the car is properly set up before doing much else. Centre Gravity are the go to guys for this further south and people seem to rate http://www.atec-align.co.uk/ if you are further north (caveat: I haven't used them myself as yet but plan to do so).

 

[Gizmob73]

I second the tyre pressure suggestion, you can experiment with small differences in front and rear pressures. I find that even small differences can make a noticeable change on my 997.1 c2s. I am running 33 front and 39 rear, which is 1 psi lower than spec but I prefer that.

 

[tom_nieto]

The car is sensitive to tyre pressure for sure. I have never found this particular issue in my C2S cabrio. I did however make a beeline for Center Gravity as soon as I bought it and have never looked back. Well worth the investment.

 

[MarkAP]

I would agree with @tom_nieto, a visit to Centre Gravity will not only get quickly to the root of the problem, but also leave the car working the best it can for your style of driving. I certainly found that this in my case, money well spent, biggest improvement made to car since fitting a DSC.

 

[MikMak]

Thanks for the reply’s appreciated, little more info, I ran the car up to Glasgow, way up fine on the return noticed the floating feeling immediately straight away, since had new Pirelli’s on rear and front Pirelli’s have circa 200 miles on them, pressures are 35 & 40, it’s’ still floating on front. My indie carried out a laser wheel alignment, though I have seen more advanced technology, in theory nothing has changed if anything it’s been improved, new rears. I suppose a specialist wheel alignment at a place familiar with the brand is a starting point I guess, or hopefully the solution.

 

[Gizmob73]

Thanks for the reply’s appreciated, little more info, I ran the car up to Glasgow, way up fine on the return noticed the floating feeling immediately straight away, since had new Pirelli’s on rear and front Pirelli’s have circa 200 miles on them, pressures are 35 & 40, it’s’ still floating on front. My indie carried out a laser wheel alignment, though I have seen more advanced technology, in theory nothing has changed if anything it’s been improved, new rears. I suppose a specialist wheel alignment at a place familiar with the brand is a starting point I guess, or hopefully the solution.

It's cheap, quick and easy to test tyre pressures. Try dropping the fronts from 35 to 33 and rears down to 39. It made a lot of difference for me and you've got nothing to lose, you can always put it back up again.
Not saying this is the problem for you, but if I run my fronts at 35 it feels a lot worse and certainly more floaty.

 

[MaxA]

It is in the nature of the car that the front end will feel light, especially if you have come from something front engined, but I'd follow the advice re Centre Gravity and also fit a DSC controller (as it certainly improved the porpoising on certain roads). On the mechanical side, it could also be that your dampers are getting tired, which will not help.

 

[veetwin]

I changed pressures to 33F and 36R and it helped a lot to reduce front float

But, not as much as the DSC Controller and Fast Road Geometry did

Worn Dampers were the next biggest improvement

Tight Front-end now, no float

 

[Punchdrunked]

Interesting one. If the tyre pressures are within spec and the alignment has been done, the fault lies elsewhere. To add to the other suggestions, have you changed the engine mounts? Changing mine made a big difference but it was more rear biased rather than front.

That said, these cars can feel a bit light at the front but not in a straight line. Good luck.

 

[veetwin]

Mine felt light in a straight line, prior to the above remedies. Horrible to drive.

Worst was felt between 60-80 on Dual Carriageways/M-Ways.

 

[KarlRS]

Front end of my C4 cab 997.2 was floaty following a complete suspension refresh. A full Hunter alignment and DSC controller transformed it

 

[rga997]

Mine did that after the wheels were refurbed - I forgot to check the tyre pressures! Doh!
Corrected them and the cars is now stable again!

Assuming the geometry is good, suspension/steering components are good & the tyres are also good - check the pressures.