Wheel size & spacers

[acat2002]

I am looking into ordering a set of winter wheels/tires for my 2008 Cayenne Turbo.

I know there has been much said about the suspect quality of non-OEM wheels, but unless anyone has direct experience with this particular supplier, we can (for the sake of discussion) assume that these wheels are legit. Here is what I'm looking at:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=270613995652&ssPageName=ADME:X:RTQ:MOTORS:1123

or item #270613995652 if the link does not work.

I currently run the stock 21" sportplus wheels and although I have the sport design package and wheel arch extentions, I do NOT have the ceramic brakes or the Turbo S brake setup. Just stock turbo brakes.

Do I need a spacer with an offset of 60 on 9" rims? if so, what size?

Has anyone set their turbo up similarly?

My thought was to go with one size down rim (20" vs. 21") because we are plagued with bad asphalt up here in New England and for the winter season at least, more sidewall is a better way to go. I'm also going with black so that it won't show the road grime (and also they will look pretty aggressive on the white Cayenne) I'll tackle tire selection later, but my first thought was Scorpions.

Any helpful input or suggestions would be gratefully appreciated.

Thanks,

-A

[Loren]

On a 9" wide wheel 60 mm is the correct offset - so yes, they would fit. Sorry, can't speak to the quality of these wheels.

[acat2002]

Thanks Loren, you're always helpful.

[acat2002]

Couple of more questions for you guys:

I intend on setting up the winter tires/wheels a a complete stand-alone set and don't want to swap the TPMS sending units.

What do you recommend for a TPMS sending unit in the new wheels?

Can I go with a universal aftermarket sending unit, or will the Porsche TMPS only work with Porsche sending units?

I imagine the Porsche units are well over $100/ea.

Also, I just noticed that the offset on the stock "sport" rims (the ones w/20spokes that look like a turbine found mostly on the Turbo S) on my urbo are:

ET50 on the front

ET45 on the rear

Therefore, I would assume that as you stated Loren, that 60mm offset on the new wheels will be fine.

I guess I'll see when I receive them

[acat2002]

Well, I received the new 20" GTS wheels.

All 4 are 9x20 ET60. No tires mounted yet, but will ilkely go w/ Pirelli Scorpions.

Current Sport Plus wheels are:

10x21 ET45-Rear

10x21 ET50-Front

Although the new wheels clear brakes, hoses and other suspension components with no problem, the stance will be all wrong with new 60mm offset using the new wheels. I have wheel arch extensions and the new wheels will appear too narrow (being retracted from the outer wheel arch by 23mm in front and 28mm in rear). I used this ET offset calculator: http://www.1010tires.com/WheelOffsetCalculator.asp

Not looking to get crazy with widening the track, but it appears that I'll need a minimum of 23mm spacers at front and 28mm at rear to keep the stock track and stance. I see that H&R sells a "Track +" spacers of all different widths.

I also understand that there is a TSB floating around that suggests that maximum spacer of 17mm should be used (if the existing bolts are being used). It seems as though I'll have to consider the "DRA" type spacer that bolts directly to the axle, then the wheel bolts to the spacer. I realize that there are other mitigating factors such as if the new wheels have the proper recesses to receive the bolt heads protruding from the spacer face when mounted etc. Also need to make sure that I order the correct bolt length and shoulder type.

Does this make sense to anyone out there?

Most importantly, is this a big "no-no" in terms of safety, warranty etc.?

I'm mostly looking for a few opinions regarding the basis for these assumptions (ET offest calculations and the applicability of H&R spacers)

thanks in advance,

-A

[acat2002]

I meant to update this thread weeks ago after I finally sorted out the winter tire/wheel package.

So here it goes.

I went ahead and purchased a set of (4) 20x9 black GTS-style wheels from OEM Wheel Plus (you can find them on fleabay and on the internet)

All four have an offset of 60ET and the staggared 21x10 wheels on my 08 Turbo were 50ET (front) and 45ET (rear). I wanted to keep the same offset and stock apearence of my Cayenne. So, allow me to pass on what I've learned from the experience:

1) WHEELS - I wanted to go down one tire size for the winter, so I found 20" wheels. While OEM Wheels Plus was good to deal with (prompt shipping and reasonable $800 price for all four), you definately get what you pay for. THey're not terrible and to the untrained eye, they look like perfect GTS wheels. However, I noticed that the inner part pf the wheel does not have the same glossy finish as the outside, nor does the inside of the lugnut recesses. You can't really notice while they're mounted, but would it have killed them to spray the inside of the rim before baking the finish? Also, the centercap Porsche logo is clearly a cheap Chinese label. Again, you can't tell from a curbside impression, but real Porsche crests have a nicer finish. I realize that the company probably cannot legally provide real Porsche crests. Overall, I'd give these wheels a "B" for a grade, but we'll see how I feel after a winter of NewEngland roads and if the first pothole warps them up.

2) SPACERS - The folks at GMP Performance in N.Carolina seem to know thier stuff with Porsches. The sales rep I spoke with (Stephen) took all the time needed to thoroughly understand what I was trying to accomplish before setting me up with H&R Trak Plus spacers (Type DR) and the appropriate longer lugs. The formula I used works perfect and consists of 18mm spacers for the front ($130) and 23mm spacers on the rear ($140). Lugs were another $200. I'd give these guys an "A-" overall. Would have been an "A+" except that two weeks after I ordered the spacers I called to check the status only to find out that they had been backordered - thanks for the notification! Wasn't a big deal this time b/c I was in no hurry, but imagine if I was sitting by the doro waiting for the UPS driver all week. Most importantly, the total track width and look is identical to stock - which is what I wanted.

3) TIRES - Pirelli Scorpions Ice&Snow 275-40-20. (106 load rating - V speed rating). I definately notice that the handling is not as sharp and there is a lot more road noise compared to the P-zero N-Spec tires I was running in the summer. I guess that is the price one has to pay for being safe in the winter. I'll report back at the end of the winter to tell you how the actually performed in the snow.

4) TPMS - After too many hours of research I gave up and had originally called Tire Rack (despite the warnings). The sales rep I spoke with was pretty knoledgeable and I repeatedly advised him that I'd been warned that Tire Rack had send out incorrect sensors in the past, but he assured me that they have learned from their mistakes (he sounded genuine). He offered me two decent choices. First he said they had a pair of "used" sensors for $50/ea, but I figured that I'd rather go for the new BERU units for $99ea (including sensor and stem).

So, after getting all my stuff organized and ordered I scheduled a service with my local Prosche dealer for install and to advise them that a tire/sensor package would be arriving on my behalf. Surprisingly, instead of them squirming about installing Tire Rack stock, they offerd to try to beat their price. I was totally shocked. In my 10 years of experience with this dealership, this was the first time they had ever offered to try to SAVE me money. Sure enough, they were able to get the sensors/stems (and tires) for the same price as Tire Rack. Ironically, the tires themselves came through their wholesale account at Tire Rack.

Of course they boned me for $100/ea for "roadforce balancing" and mounting, but hey, after already spending $1,375 on the wheels, lugs and spacers, I was not about to blow this thing up by takling a chance on incorrect sensors. I think I current sit at about $3,400 all in.

White Cayenne TT w/ Sport Design package, black grill inserts and now with black GTS-style wheels.

I'll post some pictures later, but trust me it looks fantastic.

One intersting note is that after the install I had a bad vibration between 70-85mph. Called the dealer to explain the vibration (fearful that my choice of aftermarket wheels would come back to bite me) and they said give the suspension a chance to "settle" after spending several hours on a lift. Sure enough, the next day after finding astretch of road top open her up to 130mph, the vibration vanished. Although I'm still not totally comfident in the Pirelli Scorpions for extreme driving.

Edited November 13, 2010 by acat2002

[acat2002]

As promised here are some photos of the winter tires/wheels (some show how the offset/track is nearly identical to stock.....if not a few mm shorter so the rocks and gravel won't kick up on the paint).

[CTTinTO]

I meant to update this thread weeks ago after I finally sorted out the winter tire/wheel package.

So here it goes.

I went ahead and purchased a set of (4) 20x9 black GTS-style wheels from OEM Wheel Plus (you can find them on fleabay and on the internet)

All four have an offset of 60ET and the staggared 21x10 wheels on my 08 Turbo were 50ET (front) and 45ET (rear). I wanted to keep the same offset and stock apearence of my Cayenne. So, allow me to pass on what I've learned from the experience:

1) WHEELS - I wanted to go down one tire size for the winter, so I found 20" wheels. While OEM Wheels Plus was good to deal with (prompt shipping and reasonable $800 price for all four), you definately get what you pay for. THey're not terrible and to the untrained eye, they look like perfect GTS wheels. However, I noticed that the inner part pf the wheel does not have the same glossy finish as the outside, nor does the inside of the lugnut recesses. You can't really notice while they're mounted, but would it have killed them to spray the inside of the rim before baking the finish? Also, the centercap Porsche logo is clearly a cheap Chinese label. Again, you can't tell from a curbside impression, but real Porsche crests have a nicer finish. I realize that the company probably cannot legally provide real Porsche crests. Overall, I'd give these wheels a "B" for a grade, but we'll see how I feel after a winter of NewEngland roads and if the first pothole warps them up.

2) SPACERS - The folks at GMP Performance in N.Carolina seem to know thier stuff with Porsches. The sales rep I spoke with (Stephen) took all the time needed to thoroughly understand what I was trying to accomplish before setting me up with H&R Trak Plus spacers (Type DR) and the appropriate longer lugs. The formula I used works perfect and consists of 18mm spacers for the front ($130) and 23mm spacers on the rear ($140). Lugs were another $200. I'd give these guys an "A-" overall. Would have been an "A+" except that two weeks after I ordered the spacers I called to check the status only to find out that they had been backordered - thanks for the notification! Wasn't a big deal this time b/c I was in no hurry, but imagine if I was sitting by the doro waiting for the UPS driver all week. Most importantly, the total track width and look is identical to stock - which is what I wanted.

3) TIRES - Pirelli Scorpions Ice&Snow 275-40-20. (106 load rating - V speed rating). I definately notice that the handling is not as sharp and there is a lot more road noise compared to the P-zero N-Spec tires I was running in the summer. I guess that is the price one has to pay for being safe in the winter. I'll report back at the end of the winter to tell you how the actually performed in the snow.

4) TPMS - After too many hours of research I gave up and had originally called Tire Rack (despite the warnings). The sales rep I spoke with was pretty knoledgeable and I repeatedly advised him that I'd been warned that Tire Rack had send out incorrect sensors in the past, but he assured me that they have learned from their mistakes (he sounded genuine). He offered me two decent choices. First he said they had a pair of "used" sensors for $50/ea, but I figured that I'd rather go for the new BERU units for $99ea (including sensor and stem).

So, after getting all my stuff organized and ordered I scheduled a service with my local Prosche dealer for install and to advise them that a tire/sensor package would be arriving on my behalf. Surprisingly, instead of them squirming about installing Tire Rack stock, they offerd to try to beat their price. I was totally shocked. In my 10 years of experience with this dealership, this was the first time they had ever offered to try to SAVE me money. Sure enough, they were able to get the sensors/stems (and tires) for the same price as Tire Rack. Ironically, the tires themselves came through their wholesale account at Tire Rack.

Of course they boned me for $100/ea for "roadforce balancing" and mounting, but hey, after already spending $1,375 on the wheels, lugs and spacers, I was not about to blow this thing up by takling a chance on incorrect sensors. I think I current sit at about $3,400 all in.

White Cayenne TT w/ Sport Design package, black grill inserts and now with black GTS-style wheels.

I'll post some pictures later, but trust me it looks fantastic.

One intersting note is that after the install I had a bad vibration between 70-85mph. Called the dealer to explain the vibration (fearful that my choice of aftermarket wheels would come back to bite me) and they said give the suspension a chance to "settle" after spending several hours on a lift. Sure enough, the next day after finding astretch of road top open her up to 130mph, the vibration vanished. Although I'm still not totally comfident in the Pirelli Scorpions for extreme driving.

Acat2002 - do you know what length of bolt the sold you for the 23mm spacers?

[acat2002]

Acat2002 - do you know what length of bolt the sold you for the 23mm spacers?

I went through my materials again and it appears I mistakenly wrote 23mm spacers for the rear, when in fact I used 18mm spacers.

To answer your question though, the new bolt size GMP Performance sold me was 14x1.5x48mm, so 48mm.

The front spacer was 15mm and the correct bolt is 14x1.5x45mm

I recommend that you call GMP Performance as they will be able to help no doubt.

Good luck

[odix]

Looks great! Thanks for following-up and posting the pics.