968 wheels - size advice please

[Mr968]

checking my avatar you'll see that I had the 18" 5 spoke Carrera wheels fitted, looked great but I changed back to 17", with the M030 ARBs, the 17" wheels just gave slightly better ride comfort, enough to make the difference.

As somebody has mentioned previously, it may also be down to the tyre side wall being narrower/stiffer and therefore less able to flex.

 

[jptoon]

Pity those Carrera wheels were never produced in 17" they look so good on a 968.

 

[Super_Marv]

ORIGINAL: Chrishazle

ORIGINAL: Super_Marv

Sorry, just re-read that and it doesn't quite make sense - I meant check to see if your car has the old style caster bushes and if it does, upgrade them to the newer type!

Newer type at the top, older at the bottom:

Marv, what's the reason / benefit of this? Hartech call it the front wishbone rear bush (at £35, no doubt plus VAT and delivery) each, plus time to fit, so the upgrade is going to cost £1-200 even at Indie prices!

As far as I can tell, the updated bushes are more robust. I assume Porsche specified them due to the extra weight of the 17" wheels putting additional forces against the original bushes, which they couldn't take. I can't say for sure, of course, as I'm not a Porsche suspension engineer! I'm just going by what they recommend.

A quick google reveals what happens when the older style bushes start to break apart:

Quite alot of the 944 crowd update their caster bushes to the newer 968 style bushes and report that they made a good, positive amount of difference to how the car handles.

 

[Chrishazle]

Thanks Marv, I've got the front of the car up on axle stands at the moment, wheels off (just dropped the PU to replace the piping, contemplating oversill removal next!) so I can have a look at the state of the bushes once this filthy weather improves! Have also been told I need new engine mounts and a tip gearbox oil/filter/gasket change in the not too distant!I've spent more on the cab in 3 months than I spent on the coupe in 5 years!

 

[Super_Marv]

ORIGINAL: Chrishazle
just dropped the PU to replace the piping

That's one of my jobs when I get back from holiday! What is the new piping like? The current ones on my car are very hard. I think they may have become this way with age. Are the new ones soft? Are you stapling the new ones on, or are you going to use some silicone sealant?

I've also got to replace the door handle gaskets..

Sorry for the thread hijack!

 

[RHT45]

ORIGINAL: 964RS_DAB

I think 17s will be fine as Porsche supplied 17s as standard fitment on many 968s. 18s will undoubtedly be harsher and noisier due to lower profile tyres.

If you decide to go for 17 Cups - make sure you get the correct offsets, 968 Cup wheels are quite hard to find, as Chris says, you'll probably be looking at a cost in the region of £1k

IIRC the correct 968 offsets are:

Front 17 * 7.5 ET65
Rear 17 * 9.0 ET55

And here is what you should see - apologies for poor quality pics:

 

[Chrishazle]

ORIGINAL: jptoon

Pity those Carrera wheels were never produced in 17" they look so good on a 968.

There's a set of 17" Carrera4's on eBay right now, but I'm not 100% about whether the full spec is suitable for a 968.

968 spec is front 17x7.5J ET65, these are 17x7J ET55
968 spec is rear 17x9J ET55 which these are.

Link : http://www.ebay.co.uk/itm/Porsche-911-17-Carrera4-Alloy-Wheels-Pirelli-Tyres-/230663020474?pt=UK_CarParts_Acc_Wheels_tyres_Rims_Car_Wheels_ET&hash=item35b4965fba

 

[Big Dave]

Chris.
Those arnt the same Carrera wheels as stu is talking about,
Yes they are off a Carrera 4 but if you look closely at stu,s avatar they are a totaly different wheel.
The Carreras stu is on about have a very thin spoke. they are a very nice wheel. i had a set some time ago, but never got round to fitting them.
They never made them in a 17" wheel...

 

[Chrishazle]

Dave, please be quiet, I'm negotiating with Richard and hoped JP would be tempted by the Carreras![][]

 

[Big Dave]

Ok,,,,, OOOPPPs.....[][][][]

 

[jptoon]

So you're the competition Chris !

Dave's right those Carrera's aren't the ones I liked, I much prefer Richards Cups !!!

 

[galwaytt]

When I bought my manual Coupé, it had 17"s and I didn't like them one bit. I re-fitted the 16"ers and the comfort is much, much better, and the car quieter.

Have done the same on my Tip coupe as well.

As far as I can see, anything bigger is only a cosmetic benefit. Oh, and 16" tyres are cheaper, too !|!

 

[jptoon]

Well I eventually done a deal with Richard and now have his 17" cups fitted to my car, after I had them fully refurbished and powder coated at my local alloy wheel specialist.

I also went with Toyo tyres after seeking advice from several sources and I must say the ride is no more harsh than it was with my 16" cups that have Dunlop Sports fitted.

If anyone is in the market for a set of genuine 16" cups, please drop me a line.

 

[Chrishazle]

I had a long talk with Cliff at Project Nine last week about wheel sizes for my cab, and his advice was that anything that firms up the suspension/ride on a cab has the side effect of making the scuttle shake and creaks even worse than it currently is. I am quite happy with the handling on 16's, just need to get some silicone lubricant in a couple of places and try to get rid of some of the squeeks. Sometime soonish I'll look at replacing the castor bushes and front ARB drop links and bushes, but I've decided I'll stick with the 16's.