Wheel Spacers

I have a completely stock 04 996 with 18" wheels and M030. I was wondering if the 5mm spacers will do anything at all to enhance the appearance. 5mm is not very much, and I'm thinking that the effect of filling the wheel wells won't be apparent without lowering. I'd like to hear if anyone has done this and been happy with the result. thanks.

I went even smaller with a 4mm, and yes, it actually does make enough difference to notice. I had them on my Carrera 5 spokes in the front. I went with 295's in the rear, so it was unnecessary. It's a good look. And with your suspension, it will fill out the wheel well nicely.

Go with 15mm or more... IMO...

I went with 6mm all the way around and folks are correct. It's only 1/4", but it does make a difference!

OK. What are the other tradeoffs for 4,5, 6, or 15. Will alignment be affected? Crud thrown on the side of the car? Steering or rubbing issues? thanks

Agree 5mm was very noticeable, appearance wise. 4mm or 6mm--probably a hair less/more. I went with the GT3 wheel spacer kit to keep it factory and still have wheel locks. Alignment won't be affected. Porsche originally made the GT3 spacers to fit larger brakes. Rubbing issues would depend on what you have for wheels/tires. A lot of people have used them to make small changes in offset to clear coil-overs, etc. Porsche puts the GT3 spacers on the Boxster 550 SE from the factory. This and on the GT3 leads me to believe there are no wheel bearing wear issues. Actually, factory wheels can vary slightly in offset. With all that said, the Porsche ones are expensive at around $400 from the dealer, but they fit absolutely like a glove with all the right retaining screws, etc., and no balance problems. I didn't have to dink around with grinding off and changing the collars as with aftermarket bolts. I'm using them on my 17" wheels, but I just got a set of aftermarket 18" with very "aggressive" offsets, so I will probably be selling my GT3 wheel spacer/bolt/lock set. PM me if interested. Unless you're running 9" rears, I think 15mm is too much. If you go with 15mm in the rear for a narrow wheel, you should go 5 to 10mm on the front depending on the OE offset. There is not enough room in the front to go much more outboard depending on your tire size. For example, my 235s just start to rub the inner wheel liner at full lock. 225s or 205s should just barely clear. Good luck.

Just remember, you need longer bolts with 5, 6mm spacers. Ralph Boothe, Precision wheel both make them and you can just bolt them on without stripping the stock collars.

C4S is correct. You should get 38mm bolts with those spacers. I bought my 6mm spacers from Boothe because I wanted the extra 1mm, and his fit perfectly. So I also bought his chromed 38mm bolts w/o locks. They look so much better than stock....and his have movable collars (unlike the pic)

Ask me how I know? I bought the RB spacers from a retailer who said they could be run with stock lugs, well you can't. I ran it for three days and was scared the wheel would fall off, so I finally got some longer bolts, unfortunately one of my lugs was partly stripped. I'm going to attempt a repair of the threads/helicoil and try and avoid replacing the hub, which would be way more expensive than the freakin' bolts in the first place. Just buy the spacers and bolts from Ralph Boothe and be done with it, runs about 250$. The Porsche setup is just as good, around 400$

Do any of you have a contact number/website for Ralph Boothe?

I think it is ralphboothe.com, just google it.

I think it's www.boothedesign.com Tell Ralph I sent you! His wheel center caps (among other things) are amazing!

Regarding C4S Surgeon's experience: For most conditions minimum thread engagement should be 1 1/2 x bolt diameter. There are variables such as type of thread and material hardness but this simple rule of thumb has worked well for me over the decades. I also fully endorse helicoil inserts if properly applied. They are amazingly effective at fixing screwups.