Diabolis

12mm for the front, and if you're running 265 tires in the back, *I* would probably go with 12mm for the rears as well, simply because the correct length bolts are readily available. If you can get 37mm or 38mm shank length bolts (check with the guy that just posted here - WORLD MOTORSPORTS I think), then a 10mm spacer in the rear may be a safer option as you may have rubbing issues with a 12mm spacer depending on the actual tires.

My track Toyo R888s are 265/35-18, but have a very square shoulder and (unshaved) are the same width as my street Michelin PSS 275/30-19s. Both of these look like they're about 10mm wider than a 275-sized Continental. It depends on the tire.

There's a C63 owner on the board here that is lowered and running 12mm front & 10mm rear spacers with the OEM 19" multi-spoke AMG C63 wheels. Will find out what his nick is & PM it to you if you want to ask him where he got his rear bolts.

Cheers,
Doug

olszowa12

I had 235/35/19 front and 275/30/19 rear Pirelli P-Zero.

Check this out:
235/40/18 = 94mm sidewall
235/35/19 = 82,25mm sidewall

18" = 450mm So 450 + 2x94 = 638mm
19" = 475mm So 475 + 2x82.25 = 639,5mm

So in this cas, it doesn't make a difference whether you are running 18" or 19".

Diabolis

That is the overall wheel diameter, not the section width which may be issue here.

olszowa12

I am aware of that, but the OP asked me if I had 18" or 19" when running 235/35 and 275/30

Diabolis

Right - it is Roswell. I don't know what tire sizes he is running though. Khmergod, you may wish to PM him and find out re tires and bolts.

khmergod

Didn't think 2mm difference would be so much trouble. Lastly, would I need to get an alignment after spacers? BTW I love this forum. I learn something new just about every day.

Diabolis

Duh - sorry about that. I missed it.

BTW, that is a beautiful ride! I really wish the C63 estate was available in Canada.

khmergod

^

m a x i m u s

he told me he was running stock widths (235/255) on 19" wheels.

khmergod

pmed him, hope he responds. I wonder where he got his rear bolts.

Diabolis

There are two issues with using 5mm spacers. The mounting flange on the hub is about 7mm deep, and the first couple of millimeters of the hub bore on most wheels is tapered, which means that you have no way of perfectly centering the wheel, which will likely result in some vibration. Furthermore, there is now no vertical (weight-bearing) contact between the car and the wheel itself, so the wheel bolts alone are now essentially supporting the entire weight of the car as well instead of simply clamping the wheel to the hub. While it may not vibrate badly if it's on the rear and/or if you just happen to get it right by the bolts alone, I personally wouldn't take the chance for the reason I stated earlier.

There are no issues with using spacers if it's done right (Porsche has been using them for years in both street and race cars), but the key here is doing it RIGHT.

m a x i m u s

interesting, i never thought of that. so in your opinion the minimum safe size is 10mm?

Diabolis

Well, I suppose you can always get 40mm bolts and get a shop to shave them down a couple of millimeters. A carbide steel saw blade should cut through them without too much difficulty. You can use a Porsche lug nut (also M14X1.5) as a guide.

khmergod

Another question Diabolis. What's your opinion on 12mm front or 15mm front?

Diabolis

Well, the 10mm H&R spacer is the smallest one that has the hub-centering flange, but seeing as it has to be hub-centric itself, there's only about 2 to 3mm of material for the flange at the thinnest point. AFAIK H&R uses 6061-T4 or -T6 alloy which is pretty strong stuff, but obviously the more material there is, the smaller the chance that you would shear the spacer itself. With a 12mm spacer, you now have about 5mm of material between the inner bore and the outer flange, which would be quite safe.

If you're trying to visualize what I am talking about, have a look at http://www.superforma.co.uk/hubcentric-explained - they have some nice diagrams and a pretty good explanation of the whole concept.

Diabolis

Structurally, both would be quite safe assuming that you get the correct bolts for each (40mm or 43mm respectively). As for fender clearance, I have no idea whether the 15mm spacer in combination with your particular rims, tires and suspension mods (and the weight of the car's occupants/contents) would result in rubbing.

The consensus seems to be that 12mm spacers will clear fine, but I am afraid I can't offer any advice beyond that.

Roswell

I'm the one running 12mm front (235/35/19) & 10mm rear (255/30/19) on oem 19's multispoke & H&R springs.. No rubbing at all.

The front has a bit of room, so +15mm will work with a longer bolts (27mm stock + 15mm spacers = 42mm).

The rear is flush with 255/30/19, so my guess is u will rub with 12mm spacers or 10mm spacers w/ ur 265. Just my guess though as each tires has different shape sidewalls.

I'm running 40mm longer bolts all around w/o any issue. I can't explain why though. The best length would be (27mm stock + 10mm spacers = 37mm).. But at that time, I was not able to locate some 37mm longer bolts. I ordered my bolts from Essexdistribution in Vamcouver (H&R Canadian distributors). Good luck!

khmergod

Gonna be a guinea pig and go 12mm all around. Wish me luck lol. Go hard or go home!

Diabolis

You are indeed a gambler after what Roswell said about a 10mm spacer on a 255 tire being flush.

If all else fails, you can always roll the rear fenders or give it enough negative camber at the back to clear them, which would give you an even more squat stance but will unevenly wear the inside edges of your rear tires. If they're not directional, you could easily swap the rears twice a year though and get full use out of them.

Good luck and let us know how it turns out!

khmergod

I think I'll just go 12 front and 10.rear. just checked rear clearance and it's not much left. Fronts are more sunk in. I might go 15.fronts

Krotondo

do i need extended bolts for a H&R 5mm spacer? I need it to clear my coilover with my new wheels. overnighted the spacers today.

Diabolis

Unless you're OK with your wheels falling off during cornering, you most certainly do.

The minimum number of turns for an M14x1.5 bolt is about 8 turns or approximately 12mm of load bearing shaft length. If you don't get longer bolts, you will only have about 7mm or roughly 4.5 turns, which is not enough to safely keep the wheels on the car. You'll need longer bolts (28mm + the thickness of the spacer), which in your case is 33mm.

If you're using your OEM Mercedes wheels (not aftermarket -- most of those use a different seat type) and these are for the front of the car, then you can go with H&R part # 1453502 bolts which are 35mm (slightly longer bolts on the front are OK, but not on the rear where they will interfere with the parking brake mechanism as the clearance is only about 2mm). Alternatively, there was a post here yesterday by someone (WORLD something or other) that sells spacers and hardened bolts and he may also have what you need.

Having said this, I wouldn't use a 5mm spacer (another post here to maximus explained why), but that's just me. I know people who do and are fine, but I also know people that did and things ended up somewhat badly for them.

-

Diabolis

Sorry - I just saw that you wrote "with my new wheels". Are they OEM MB wheels (that use an R14 ball seat) or something else? If they're not MB wheels, then the bolt part numbers I gave you earlier do NOT apply.

Krotondo

They are aftermarket, ill do a whole write up once my cars done

So I have 12mm spacers all around now with extended bolts. Can I use those with the 5mm spacers?

khmergod

Just pulled the trigger on HR 15mm front and 10mm rears with 43mm bolts and 40mm bolts. Now I sit here and wait for them to arrive.