tommo951

Hi Guys,

I am currently using Boxter 17 inch rims on my 1991 Turbo S. I know that the offset will be incorrect. Can the wheel gurus out there let me know what spacers I need to use to get the offset correct

MTIA

Cheers
Tom

sawood12

Tom, I'm afraid I don't fall into the category of 'wheel guru' but the offset of the front stock 16" wheels is 52.3mm and my front Boxster wheels are an ET 55mm so I took the required spacer to be 2.7mm. The thinnest shim I could find was 7mm which puts my wheels 4.3mm too far outboard. I can live with that. I should really carry out the same exercise with the rear wheels. It drives much better with the spacer though. Not sure if my calcs are correct but visually the wheel does sit better in the arch with the spacer - before it looked a bit narrow.

tommo951

Hi Sawood,

Nobody else has queried it mate, I tried search but did not get anything conclusive. In fact got many differing opinions!
Anybody else have any ideas??

Slantnose!

I use them sometimes on a '89 with Hoosiers (245's & 275's) and they don't need any spacers, don't rub and fill out the wheel wells fine.

tommo951

Hi Mark,

I have them on the car with 205 and 255's at the moment. You are right they do not rub. I am just conscious that the offset is different and could therefor be compromising my geometry. Can you really go to 245 safely on a 7.5 inch and 275 on a 9.5 inch wheel??

HansB

245 does fit on front, I would not run that on a 7.5 wheel. If you look at the various manufacturerers recommendations it would take a 8.5 wheel. I have run 18*8.5 ET 48 with 245's for 2 track years without any problem.

Also, looking at all of the other racers, ET differences up to 10 Front do not cause problems geometry wise. 20 and higher causes the steel structure of the tires to break.

Rear ET is not a real problem, in theory only the higher wear of the wheel bearing could cause problems. 275 on a 9.5 wheel could just work.

One other point to tire width: Various manufacturers measure tire width differently. Dunlops e.g. mention thread width, most others tire width. So in practice Dunlops are 10-15 mm wider as many other tires. I run Dunlop 290 Rear, and they are even a bit wider as Pirelli 305's

tommo951

Anotherquery is that I am considering buying some 19" rims from evilbay http://cgi.ebay.com/ebaymotors/19-PO...mZ220121744134
Has anybody bought from this firm before? Will the 11" be ok on the rear?
Will spacers be required? Offset 42MM-F, 40MM-R
What tyres would be recommended? As i will be ordering international US to UK I need to get this right

sawood12

Tommo, if you go onto the PCGB forum and do a search you'll find loads of threads on wheel offsets and some have links to calculators so you can calculate the spacers you need for a given offset of wheel. I would post you a link but I cannot access that forum from work!!

333pg333

I think they'll stick out too far Thommo on a late model like yours. I have a set of 18" that are 9" et 51/255's and 10" et 60/285's.

Slantnose!

Yes, absolutely this is a fine and safe fitment.
Also, the 275 will work on just a 9".
Check the the Hoosier Tire site www.hoosiertire.com and see the specs.
These sizes are within their recommended rim widths.
Hope that helps.

JE_951

I run 18X8's in front with 245's and 18X10 with 285's in back and they are about as big as I can go. The front would rub with anything bigger and the rears are VERY close to the inner fender well. IF I put on 295's I think it would rub. I also cannot do spacers since it will probably rub the quarterpanel.

I run the 18" carerra 5 spoke wheels. not sure what teh offset is.