AMGonFire

I have been doing a lot of research on drag radials and rolling diameter. Here is my problem. I'm looking for a drag radial I can drive to the track and back home not daily thing. It's 50 miles one way with some highway driving. As far as options I hear good things about the Hoosiers dot drag radial. however I have heard mixed things about driving it on the street, they say no others say they have? Now the mt drag radial 2 sounded like my best bet for what I wanted but they do not make them anymore apparently. That leaves me with the new mt ss or mt r. I have not found much on these. Now sizing is where the problem exists. I need help on the rolling diameter if it's larger is that a bad thing? What would you recommend a 17 inch rim I have one in mind or an 18 inch rim? Basically my options with the mh ss tires is a 275/45/17 with a 26 rolling diameter but requiring a 9 inch wheel which is hard to find with a correct offset. 285/40/18 with a rolling diameter of 26.9. In the mt r there is a 245/45/17 with a rolling diameter of 25.7 closer to stock however worried the 245 is a little to small? If the pros out there can help me I would greatly appreciate it thanks.

mr747

if im totally honest anything bigger then 225 size on c63 is crap the tyre is too tall and doesnt match ratios of gearbox if you want to stick with MT tyres or MH tyres i wouldnt go bigger then 245 that should suit your application

i have tried and tested 255 50 16 and they simple dont cut a good 60ft time

AMGonFire

do you think the traction will be good with a 245?

mr747

i done a 1.64 60ft with 225 50 16 hoosiers and a 1.45 with 215 60 15s but broke the gearbox

yes yes it will hook with those 245 tyres

bigger tyres doesnt mean it will hook better its a combination

Hagi hooks with 225 50 16s

604 C63

in all sincerity, please pardon my ignorance here. For the life of me I dont understand how this can be the case. I know its true that you are running something narrower (cos I follow you on FB and have seen pics) but I cant wrap my brain around a 215 hooking better than a 275. Only thing I can think of has to do with not width so much as sidewall and how those two relate to each other.

Would you mind explaining this to me? Thanks in advance.

BLKROKT

IT has to do with effective gear ratios. The 215 tire, while skinnier, is also shorter. It lowers the effective gear ratios, and gives much better acceleration. The stickiness of the drag radial/slick more than makes up for the decrease in width.

And forgot to add that he only needs a certain xx" of sidewall to cushion the drivetrain and provide the right flex per hp he's putting down. He figured the optimal sidewall height. So moving down in rim size while still maintaining that right sidewall, results in the shorter overall rim/tire height. 215 is probably the widest tire he could find in that rim size and sidewall height.

Schulminator

Is there a 16" wheel that will fit the rear w/o brake mods?

604 C63

Thanks!

BLKROKT

Yeah I just looked around and Hoosier makes a 295/50-16, but I can't imagine how he'd make it fit, and the sidewall might be too high. Doesn't seem to be many options if any in between.

In drag racing, there's such a thing as "too much tire". I thought this was interesting: http://www.onallcylinders.com/2016/0...icks-traction/

s.e.a.n.

A member had these for sale a few months ago, however I am not sure how well they work.

mr747

Best explanation ever thanks bro

You explained it alot better then i could ever do lol
thank you

But exactly this

mr747

you can run a 20mm spacer and use 225 50 16s and they fit fine

you need to trim a little off the pads which is not a big deal

Asher4799

I had to use a 35mm spacer to fit over my rear brakes with trimming the tabs off the brake pads. Also using 16in CLK wheels.

AMGonFire

Thanks for all the input on this. A lot of good information here. However I don't think I want to run a 16 inch rim. I have decided on a 17 inch rim with The new MT SS drag radial in 275/40/17 which gives me a rolling diameter of 25.66 which I don't think is much off stock size. Now the help I need is will an 8 inch rim fit these? Minimum recommendation is 9 inches. I have seen guys put them on 8 inch rims but not sure? How will that work for highway. I know what size rim will work if I go the 8 inch wide route 17x8 et 45 seems to have worked for many. Now the same style rims I like are available in a 17x9 et 50 will this fit?? I'd rather go the 9 inch wide route because that's what's recommended but haven't seen anyone run that size rim. Thoughts please??

BLKROKT

I think you're looking at it from the wrong perspective. The biggest benefit in going to dedicated drag wheels with slicks on these cars, is in lowering the gear ratio to allow for faster acceleration. It's not about traction necessarily. You're not likely to see a big benefit is trying to keep the rolling diameter close to stock (for reference, I cut better 60' times with MPSS than with drag radials of the same size).

AMGonFire

i understand that concept however my concern is traction. I have mpss they are not going to hook like a drag radial. There are no options out there to run a smaller overall diameter. I am not going full on slick I want to be able to drive to strip and drive home. Reading through all the forums alot of guys ran the mt et street II which where 265/something/18 right in the same ball park as stock rolling diameter. The et street ss replaced those. They where pulling better times with better 60 foots with those over summer street tires. That's what I want. I'm trying to figure out if the 17 inch rims I talked about above will fit. Going 17 for weight purposes and it keeps the rolling diameter down. There just arnt a ton of options out there.

Asher4799

The 17 will probably work, now before I went to dedicated slicks I used 285/30/18 nitto 555r and was able to cut consistent 1.7 sixty'S and many high 1.6 sixty's the biggest part was figuring out air pressure "15.5" psi with having to do a really big burn out, once that was figured out they worked great. So with running a 17 with a 8-9 with and correct offset you will be fine.

604 C63

Gotcha. This part you added in really brings that together, and was kind of along the lines of what I was thinking. Sort of. Enough so that I dont feel like a complete moron anyways

604 C63

This was an excellent read. Thank you.

AMGonFire

just have to figure out how I can know the 17x9 et 50 rim will work without buying one and test fitting. To me if a 17x8 et 45 fits like few others have done why wouldn't that?

ritalin

You will have no issue fitting that width.
The only think you need to check is how narrow the barrel gets on the inside of the rim.
I have the 17 x 7.5 enkei rpf1 w a 12mm spacer because the barrel drops down to 15 3/4 on the inside. Once the spacer is on, it offsets the wheel so that there is clearance between the barrel of the wheel and the brake caliper. They work really well like this. I did shave the brake pad tab as well for peace of mind.
Not a big deal.
This car, mainly due to the transmission does not require a bigger tire at all.

AMGonFire

how can I find that spec of the inner barrel size? Also what tire are you running on that setup?

ritalin

The problem is, you can't. Unless someone has already purchased and measure it. Or has one in stock for you to see.
225/45/17.

glennhl

I've got a set of almost new 275/40-17 Nitto 555R drag radials mounted on 5 spoke C300 wheels. Fit fine on the back of my 2011 C63. Perfect for driving to the track and running. If you are interested please PM me. Thanks, Glenn

C63fora2w1

As some of you may know I come from a drag racing background had have a little experience with this subject. Generally you want to run the widest tire you can possibly fit to achieve the best grip. I agree that overall diameter plays a big role and thats why the second number (275-XX-17) makes a difference. You want enough sidwall to allow the tire to flex and grip. I used to run the MT ET's 26x9x15 and would routinely pull a 1.68 60ft in a first gen camaro with 450hp and 480 tq. The drag radials are a compromise on performance but are still good. I can vouch for the Nitto 555R's they hook hard and MT is also a good bet.

There are some good calculators out there to help u figure your tire diameter and effect on final drive ratio witch affects ET. http://www.wallaceracing.com/calc-gear-tire-rpm-mph.php

www.wallaceracing.com/Calculators.htm

Hope this helps.