kiwi 911

No - coz D90's can have low profile tyres too 225/40 and 245/40's.

Smaller rims accelerate better as their is less tire friction (narrower) and lower rolling radius (assuming you are using low profile 16's too)

kiwi 911

I thought the later cars had the 16" 5 spoke wheels (instead of D90's), but i have not doubt you could buy 17's as an option.

Looking at all my period photo's of 964's, none ever had 17's other than the RS's. Also in the early years the C2 racers (not RS rep racers) used to run 16's - refer pic's of Graham Cameron's car - it had 16 inch 3 piece simmons (now Sean's).

peterC2S

Yes - the standard wheel was the 16" design 92 cup wheel. 17" wheels were a factory option though as by then Porsche had incorporated steering stops into the standard spec.

Pel

OK thanks

John McM

Pel, the 964 numbers are starting to dominate and we always need more fast colours (white). Come out and have a look at HD on 26/2!

Macca

I just posted this on another thread....good for your morning laugh....

Im getting old. Been refusing to use reading glasses. The font on this site is small on my Sony Vaio and Im seeing many typo and grammar mistakes due to lack of vision. Just slipped on my $2 reading glasses (we hide them and dont talk about that) and geez I can see a myriad of typos in my emails! 43 and my close vision has deteriorated from perfect to crap in maybe 9 months. Where's the bloody fountain of youth!

O2GO

Macca, on the Sunday we leave Russell and take the Old Russell Road for 1 1/4 hours low traffic rural twisties to Whakapara SH1 intersection. Then turn off SH1 at Waipu to go to Langs.

Can't recall when you arrive in nz but a couple of people have now expressed interest in joining us for the run home on Sunday. They could do the run we did a few months ago up to Langs and back again. Would you like to see if Ron would be interested?

Another alternative, depending on when you arrive here, is to shoot up to Russell and stay Saturday night with us and do the whole Sunday route back.

More info of the route is on post 9 on January 10 here:
http://www.rennsportgruppe.org.nz/fo...php?topic=57.0

Would be great to have you and others join us.

Thanks Chris. Much appreciated. John will come and collect them for the cause - LOL

I'm no expert but an engineer would be able to comment on this theory of mine.... comparing my experience with 18s vs 17s on my 987 the rolling diameter is smaller, the car is lowered by 10-15mm, and in theory there is less mass inertia sucking power to actually turn the wheels due to less overall weight (smaller rims, less overall rubber) and less leverage required (distance between hub and road contact point). Also, lower gearing which was significant.... I haven't worked it out accurately with a calculator but based on the speedo vs GPS the gearing appears to be reduced on my car by something in the 5-7% range.

Steve, who has tons more racing experience than most of us swears smaller wheels are faster :-P.

Thanks everyone for your responses on wheel sizes for 987s..... I'm blown away by the "crowd sourced knowledge" across our group and have learned a lot.

O2GO

Welcome to an exclusive club Macca.

And I thought it was just you typed in a rush and didn't proof your posts - ha ha. I'm 54 and didn't wear glasses until about 6 years ago. I got reading progressives and used them in the office and for reading. Then I got another set for driving and everyday after struggling to read road signs and even number plates of interesting cars. Wow, there was so much detail I'd gradually been missing that for the last several years I now wear glasses all the time. 20/20 vision is so sweet, it's just a bugger having to have glasses to achieve it.

Macca

Hi Doug. I fly in Saturday arvo. By the time I clear customs, taxi to storage, pick up car drive home will be late afteroon.

Thanks for the heads up on the trip South. Ill keep it in mind. Time in NZ is always precious so will have to determine first what other commitments I have to make.

Ill mention to Ron your idea but he probably prefers to organise these types of things himself as you know...

Regards the wheel tjing. I think you are right on most counts. But you haven't identified the negatives of smaller wheels which is why race teams dont bother. Changing final drive ratio via wheel diameter reduction is not desirable. A race team will change individual cogs off the main spline in order to match a tracks characteristics. This means they still have reserve for long straights. Also reduced tyre width reduces traction/contact patch and ultimately grip and lastly brake caliper clearance (increasingly difficult to find a car you can actually fit 17" too).

Macca

Yip with you on this one. Been short sited (-3.0/-3.0) contact lense wearer all my life nbow feeling very ripped off by infliction of long sightedness too. Monday in NZ Im seeing an optomertrist for an eye exam. May choose to have one eye lasered after the SITT to create a restoration of 85% visibility close work and long distance. This glasses thing sucks in the tropics.

peterC2S

Since when can you blame grammatical error on poor vision?

Thought that was just part of the Macca charm!

964X33

http://www.trademe.co.nz/motors/car-...-693807032.htm

All this talk about 16", these look good value - clearly not off a turbo.

Maxem

Hold on a minute Doug, Just one more lot of 2 cents worth even though I know bugger all about it. D90's are the boss. For track, run with them, they are lighter than most others I believe. I have a set of new dunlops that haven't been on there yet that are 1 profile lower than stock, i.e., 205/50 and 225/45 that I'd like to try. For the road, the cup 2's look fantastic. D90 **** follows;

Maxem

I saw Peter M's cayman on Tamaki drive this morning.

O2GO

Thanks Dave. Points taken. I'm loving the look of the Cup 2's in the photo you sent me yesterday. Very nice for road work and just looking at. Got it, D60 16" for the track makes sense. My reason for the side track was I have a set of 17 track wheels already. Hey, you can never have too many wheels right.... You have to agree with that given how you've cornered the 16" track tyre market with the stockpile your garage :-P

I see I got my numbers mixed up again. 987 when I meant 964 in the post above - DOH.