18" on a Turbo???

[Lemon]

Hi

I currently have 968 Cup 2 OEM alloys on my car.

They are 7.5 x 17 ET50 and 9 x 17 ET65, which is the same offsets as the original Forged ones I also have in my garage.

If I were to change to 8 x 18 ET50 and 10 x 18 ET65 would I need 6mm shims at the front for clearance and 13mm for the rears?

Or are these just too big to run on a 944.

What other 18" wheels and offsets do other Turbo drivers run without issues, or are there always going to be problems running wheels this big on the Turbo.

Just a thought []

 

[Big Dave]

Lee
IF you have a Original 968 set of wheels.. then they will be 7.5/17" et 65 fronts..
And 9/17" et 55 rears...Dont know where you got your et,s from.???? As these ARE correct 968 et,s...

I had fitted a set of 18" Sport Classic wheels to my 968 cab, many moons ago.. These were 7.5/18 et 50 fronts, and 10/18 et 65 rears. I didnt need any spacers whatsoever...APART from having clearance issues with the wheel bearing cap on the fronts. BUT that was only because the wheel centre wasnt big / deep enough...

 

[sawood12]

I've seen the 996 turbo twists on a 944 and they looked very very tasty indeed. Also Rick Cannel has the 997 Carrera 5 thin-spoke 18" rims on his car and they look equally as tasty. I think if you look on Ricks websight he mentions the spacers he used. I also think you'll probably need your arches rolled as well.

 

[Lemon]

Ah yes Dave your right

Got things backwards and missed the 5!!!!

Thanks for pointing that out

 

[Lemon]

After a bit of digging around I found

http://www.1010tires.com/WheelOffsetCalculator.asp

And with the sizes quoted the 18" wheels would be

Front: Have 9mm more clearance to the strut housing, but extend an extra 21mm out from the outside edge of the wheel

Rears: Have 23mm less to the strut housing and still extend out a further 3mm.

I think I will stick with my Cup 2's[]

Thats what happens when your car is away having work done on it, keep thinking of things to buy for it, when really you just want it back so you can drive it []

 

[John Sims]

ORIGINAL: Lemon

.....What other 18" wheels and offsets do other Turbo drivers run without issues, or are there always going to be problems running wheels this big on the Turbo.....

Have you not been to any 944 events? []

 

[Lemon]

I have seen Rick's car, they look very nice.

Do you know what offset they are? Does he run spacers?

Has he had to roll his arches as per Sawood12 comments.

Just interested, but I think I would prefer it if Father Xmas delivered a Wortec Exhaust before I bought new wheels as I already have 2 sets[]

 

[Big Dave]

Im guessing if you fit any 18" wheels , youl have to get your arches rolled.
On the 944 series they have a arch lip, on the 968,s there rolled, giving you that little bit more clearance...

In fact, talking about rolling of arches. Does anybody have a arch roller that could be "loaned" out.??? [ A proper roller, not just a hammer + heat gun...]..[8|][8|][][]

Also the 944,s seem to have "different" tolerences when built. Ie different from one side to the other... My S2 is different , clearance wise on the passenger side to the drivers side....NO it hasnt had a accident.. Thats how "some" came from the factory....[8|][8|][8|]

 

[333pg333]

It depends on the year model re the rolling. I think from '89 onwards they were factory rolled. Mine is. Also the size of the wheel isn't the main thing, it's the offset and the outside diameter of the tyre.
I have 18" with 255's and 285's comfortably. Also depends on suspension height and camber. I don't believe that spacers on the front are such a good idea, but it may depend on how thick they are. You don't want any compromise to the fastening ability of the studs.

 

[Big Dave]

Pat. My car is a 91..+ hasnt had its arches rolled... So that kind of thwarts your theory...[8|][8|]

 

[Diver944]

Pat is talking turbo cars only (we boostie boys get blinkered vision sometimes [])

I'm pretty sure that all UK Turbos have rolled arches and all S2's do not. Someone will doubtless come along with an exception to prove me wrong though []

 

[bennyboy]

Hi Lee, I've got 18x10 and 18x8.5 Speedline Allesio split rims on my Turbo and don't run any spacers at all - although I'm afraid I can't comment on the offsets. They do produce fantastic front-end grip but they also tend to tramline quite badly. I run the car on the lowest M030 settings and have no problems at all with clearance. The steering geometry needed resetting recently and I was told this was largely due to the bigger wheels and I had 968 castoer mounts fitted at the same time. Roger at Promax knows his stuff about rims and offsets so may be worth giving him a ring. Cheers, Ben.

 

[333pg333]

Sorry Dave, not trying to exclude you. [] So that's another thing you'll have to modify if you're going to forced air induction, your wheel arches.[]

 

[Big Dave]

Pat. I wonder if rolling the arches will give me any more streamlining....= faster car...[][][8|][][][8|]

 

[333pg333]

DEFINITELY Dave. Go for it!!!!!!!!!!![]
Wait until you try and cram some 11's up fromt and 12's out back! I know of one guy who has done this, but he has lots of big hammers. I'll be going a slightly more attractive route.[]

 

[Lemon]

Well I know I said I would not look anymore then these have just popped up.
7.5 x 18 ET50 and 10 x 18 ET65 Porsche Carrera alloys the same as on Rick's Turbot. Although I thought his had 8" fronts.

Not sure if they would do, but going by my calculations :
Front wheels difference between original and 18":
15mm more clearance between inner of wheel and strut housing. Outside of
wheel sticks out a further 15mm than original. Guessing this would affect handling and turn in.

Rear difference:
inner edge of wheel 23mm closer to strut housing. Outside of wheel
sticks out a further 3mm than original.

So not sure if these would do the trick, any thoughts? They are currently on a 968

 

[John Sims]

Increasing front track will improve turn in. Beaky has 6mm spacers at the front and I was suitably impressed with the difference they made.

 

[edh]

John - did you use longer bolts?

I tried a 7mm spacer & didn't have enough thread left, so took it off again

 

[Big Dave]

Lee im presuming your talking about the ones fitted to a Red 968 in Manchester..
If so, i know them + there owner well... And they are good...as far as im aware theyl fit on your car.. After all if they fit a 968 they should fit to a 944.. same chassis....

 

[John Sims]

There was some considerable debate on the forum some time ago, with regard to spacers and thread length.

I can't remember the details but I concluded mine were long enough. I had been very uncomfortable with the idea of a spacer and put off fitting them for a long time. Now they are on I haven't had any problems (yet) but they were worth it from the point of improved turn in.

Obviously the correct off set wheels would be far better.

I have said before that I think we over tyre our cars at the rear and I am pondering looking toward 235's all round.

Having said that, in anything but dry conditions, wide front tyres could be detrimental as they would be more prone to aquaplane and, in snow particularly, could be very difficult to handle.