Menu toggle

Wheel upgrade..........

wolfie308

wolfie308

New member
Since I can't afford a set of 17" Cup 1's with new tyres, I was considering the pros and con's of up sizing my D.90's

Current setup is fronts 7J x 55 offset with 205 x 55 well worn Contis, and rears 8J x 52 offset x 50 with nearly new Falken's.

Thought of swapping the rear wheels and tyres to the front and sourcing a pair of 9J x 52 offset and fitting 245 x 45's to the rear.

Just wanting to fill the arches slightly more but without introducing any tramlining or other issues. Comments/suggestions appreciated.
 
I haven't tried it myself but I believe some of the racers have used the 8" wheels on the front. It's very close to the Turbo front fit of 225/50 on 7.5". A pair of 9" Turbo rear D90s can't be too hard to find.

 
Lowtimer has beaten me to it !

IMHO, rear end grip in a 944 is generally not the problem = understeer. I've found that running the 8" D90's from the rear all round is a good cheap and practical solution.

The 9" D90's were only fitted to the late Turbos and as an option on the S2's = rare find, I reckon it's easier to get hold of a pair of CS 9" rears !

Also, by going to 8" all round on 225/50 16's you can then have matched tyres etc - makes for easier tyre management and puncture repair etc
 
If it's just cosmetic, how about spacers? might need longer wheel studs as well

failing that, 8J all round for better balance as Chris suggests
 
If you want to up the wheel size in order to fill the arch better, then Id seriously considerdowning the tyre size. Staggered wheels sizes, with 8" rears was a cosmetic enhancement on the S2 and whilst it looks better, it didnt do the vehicle any favours dynamically.

In your position Id fit the 9" rears with the current 8" rears at the front, but Id keep a 225/50/16 tyre all around. Thisll reduce the cars tendency to push but itll stick look nicer.


Simon
 
225 should allready fits nice and tight on 8" rims, Michelin cups for example run like that look nice and tight on the rim, Dunlops a little squarer. Would I run 245's all round on 9" rims? Not sure to be honest unless one was struggling to get enough traction. MarkK btw went up to 17" rims on his race car last year, I think I would rather go that way than go bigger than 225's on 16" rims.
 
Being a little stretched will firm the sidewallon the rears, but itll lead to a better match between the front and rear. Fitting 245s to the front may work, but unless the sidewalls are vertical youll probably lose a good deal of positive feel.

More wheel rim than tyre is always better than more tyre than wheel rim; although this isnt to be confused with silly 'Euro-look' stretching.
 
Stiffer and less compliant sidewalls can be detrimental to grip. Having that flexibility can allow for more tyre to be in contact with the road at all times as the suspension geometry changes as the body rolls. If you have very stiff sidwalls that are not compliant means you need your suspension geometry to be bang on and maintained as the suspension moves (which it isn't with the 944 rear suspension setup) ultimately need stiffer suspension to reduce suspension travel and the tipping/rolling of the wheel towards a tyre edge, as the body rolls, which reduces tyre contact and grip. It is generally recognised that 944's handle better on 16" rims with a taller and more compliant sidewalls.
 
Thanks for all the feedback guys. Given that this a 'budget' upgrade, looks like the only question is to stay with 8 or change to 9 J on the rears sticking with 225 x 50's. Which option do the panel favour for best handling, brisk road use only?
 
If going with 9" rear I would put 245/45 on, because that's the proper size for the wheel.

That said I am perfectly happy running my Turbo on either the S2 (7" 205/55 F, 8" 225/50 R) or Turbo (7.5" 225/50 F, 9" 245/45 R) wheels that I have for it, frankly find it a little more soulful on the S2 wheels and tyre sizes.

 
You must log in or register to reply here.

Posts made and opinions expressed are those of the individual forum members

Use of the Forum is subject to the Terms and Conditions

Disclaimer

The opinions expressed on this site are not necessarily those of the Club, who shall have no liability in respect of them or the accuracy of the content. The Club assumes no responsibility for any effects arising from errors or omissions.

Porsche Club Great Britain gives no warranties, guarantees or assurances and makes no representations or recommendations regarding any goods or services advertised on this site. It is the responsibility of visitors to satisfy themselves that goods and/or services supplied by any advertiser are bona fide and in no instance can the Porsche Club Great Britain be held responsible.

When responding to advertisements please ensure that you satisfy yourself of any applicable call charges on numbers not prefixed by usual "landline" STD Codes. Information can be obtained from the operator or the white pages. Before giving out ANY information regarding cars, or any other items for sale, please satisfy yourself that any potential purchaser is bona fide.

Directors of the Board of Porsche Club GB, Club Office Staff, Register Secretaries and Regional Organisers are often requested by Club members to provide information on matters connected with their cars and other matters referred to in the Club Rules. Such information, advice and assistance provided by such persons is given in good faith and is based on the personal experience and knowledge of the individual concerned.

Neither Porsche Club GB, nor any of the aforementioned, shall be under any liability in respect of any such information, advice or assistance given to members. Members are advised to consult qualified specialists for information, advice and assistance on matters connected with their cars at all times.

Porsche
Lockton
Pirelli
Officially approved
Oracle Finance
WEX Esso
Collecting Cars
Back
Top