QP V Sport GTS - Back end ‘wiggles’ when lifting off after hard acceleration

Harvey_Tim

Member
Messages
220
All depends how much driving, when in the year, where in the country, how fast etc etc. Temperature is probably PZ biggest issue
I think I will probably be fine with PZ‘s for now then but when the time comes to replace them I will swop for Michelin. My useage will be low mileage, mostly summer, south coast, spirited driving but not mad.

Thanks for all the responses, I am happy that the issue is more likely to be tyres than shocks, springs, bushes etc.
 

Gazcw

Member
Messages
7,845
I think I will probably be fine with PZ‘s for now then but when the time comes to replace them I will swop for Michelin. My useage will be low mileage, mostly summer, south coast, spirited driving but not mad.

Thanks for all the responses, I am happy that the issue is more likely to be tyres than shocks, springs, bushes etc.
If you have them use them and smoke them. There are alternatives that others say are just as good for general hooning around.
 

Nayf

Member
Messages
2,766
Thanks for all the replies. My local garage (non specialist) checked out all the suspension and bushes and could find no play or anything and the mechanic believes it is due to the rear tyres being (in his words) “completely shot”.

Interestingly re. MarkMas comment my car is on Pirelli PZero’s. I have 2 part worn 6mm replacement PZero‘s to put on which hopefully will improve if not fix things.

On a separate note replacing the straight pipes with the original silencers has transformed the car, my god what a difference!

Thanks all,
Tim

ps. I have some QP V straight pipes for sale if anyone is interested !
Can you take the QP on track for the next round of the BTCC at some point?
Nat/asp V8 might show up the touring cars’ fart noises a bit though…
 

AbidK

Member
Messages
144
I have the same issue with my QP, does feel a little unsettled when trying to change lanes at speed on the motorway. My tyres are pretty good though they are Pirelli’s. Almost feels like it’s going to lose the back end.
 

Gazcw

Member
Messages
7,845
I have the same issue with my QP, does feel a little unsettled when trying to change lanes at speed on the motorway. My tyres are pretty good though they are Pirelli’s. Almost feels like it’s going to lose the back end.
Yup. That's what I had until they were binned. Strangely I had Pirelli on the Strad too when I bought it and it was nowhere near as bad as the QP was.
 

Sam McGoo

Member
Messages
1,840
Obviously if your tyres are old and/or knackered they need replacing so start there.
I would then follow up with a 4 wheel alignment (at a decent place) and aim to get rid of any 'Toe Out' front or back and go either neutral or a little 'Toe in' to stabilise the handling.
Whilst doing the above, the garage will be able to advise whether your bushes are worn/torn. If so, they'll need replacing.
 
Messages
1,132
Michelin Pilot Sport 4S all round on the Gransport. Transforms the car. The best tyre by far.

Same for the Porsche. But on this I use Michelin Pilot Sport2 N-rated all round for Porsche fitment. The best for a Porsche.
 

Harvey_Tim

Member
Messages
220
So I currently have 2 almost new PZero‘s on the front and 2 rears that need changing. I can’t really justify changing all 4 so would I be better to keep same tyres all round and put new PZero’s on the back or change them for Michelins and have different tyres front and rear?
 

conaero

Forum Owner
Messages
34,794
It’s fine to mix tyres as long as they are the same across the axle. Get some PS4S on the rear. Great tyre
 

Gazcw

Member
Messages
7,845
So I currently have 2 almost new PZero‘s on the front and 2 rears that need changing. I can’t really justify changing all 4 so would I be better to keep same tyres all round and put new PZero’s on the back or change them for Michelins and have different tyres front and rear?
I had different. Michelin on rear Pirelli on front for a while. It was better with the change of rears and had no issues. On the upside, the fronts are a popular size to sell on.
 

Sam McGoo

Member
Messages
1,840
So I currently have 2 almost new PZero‘s on the front and 2 rears that need changing. I can’t really justify changing all 4 so would I be better to keep same tyres all round and put new PZero’s on the back or change them for Michelins and have different tyres front and rear?
As the others have said, it's totally fine to do that as long as its the same across the axle.
All you have to be aware of is the differing grip levels front to back.
So putting ps4s on the rear and leaving the pzero on the front will induce a little understeer if driven near the limit. But it will be fine 99% of the time.
 

cheburator

Member
Messages
162
If you get a wiggle through the back, especially after you lift off, I am willing to bet on your alignment being shot. 99% of the time you will not have the correct amount of toe-in on the rear tyres, which should be around 12 to 15' per side. The Pirellis being old and "shot" won't help for sure, but a wiggle to one side almost always points to toe-out at the rear, which allows the back of the car to steer away as the suspension bushes unload as you lift off and toe-out even more.
 

Harvey_Tim

Member
Messages
220
Hi Cheburator, thanks for that, what you say makes a lot of sense it does feel like the weight is shifting when you lift off and the car (I think) always pulls to the left as it happens.

I will be replacing the tyres and my local preferred tyre place has Hunter 4 Wheel Alignment, is it just a case of getting the alignment reset to standard factory settings (which I assume they will have on their system) or are there ”after market” alignment settings that the forum would recommend (I.e. alternative settings that specialists have come up with) ?
 

Sam McGoo

Member
Messages
1,840
Hi Cheburator, thanks for that, what you say makes a lot of sense it does feel like the weight is shifting when you lift off and the car (I think) always pulls to the left as it happens.

I will be replacing the tyres and my local preferred tyre place has Hunter 4 Wheel Alignment, is it just a case of getting the alignment reset to standard factory settings (which I assume they will have on their system) or are there ”after market” alignment settings that the forum would recommend (I.e. alternative settings that specialists have come up with) ?
As I said on post #30 above, do not use the OEM alignment settings as they have Toe out.
Change the toe out front and rear to a little toe in.
Any decent place will be able to do that for you, without you having to give them the numbers to use.
 

Harvey_Tim

Member
Messages
220
Apologies Sam McGoo I assumed you were inferring that my alignment had gone out of spec rather than that the factory spec itself was not great and had toe out.