hansjl

Moderator, sorry for posting here. I posted in tires and couldn't get an answer Yes, I did searches for 1 hour and failed to find the answer.

I have a 95 SC400 and can anyone please tell me the largest tire I can get to fill the wheel wells for my 17X8 GS400 rims that doesn't rub in the front or back. I have 235/45/zr17 now and the well looks empty. I'm stock and it will stay that way and I'm not going to lower it in the future. I'd like the largest size in height and width.

Thanks for your help!!!!!!!!!!!!!!!!!!!1

SC400Dude

how about a 245/45-17???

hansjl

The 245 gives me a 9.65 inch foot print but the height is only 4.8 inchs, the same height I have now (I believe). With this foot print can I go to a 50 or 55???????????

Looking at the current tire setup it just looks like the tires are to small in diameter. If any one in the photoshop forum would be willing to enlarge my tires , I'd be indebted. I can post a side phote of my SC. Actually, it's already posted in another thread a long while ago.

Thanks....

Baby ///M3

Hey hansijl:

I also have 17 x 8 GS400 rims on my SC4. My car's lowered with Eibach springs.

I run 245/40/17s up front and 255/40/17s in the back with no rubbings whatsoever.

I do drive aggressively once in a while and they've never had given me any problems before.

Jon

Baby ///M3

By the way, the tires I have are Michelin Pilot Sports.

Jon

qtb33

I have these wheels too, but I'm running the same 235-45-17s. I think I'm gonna run 245-40-17 next summer. i need to see how much my speedo is off first I guess

Twirl

seriousely the easiest way to see this is to take your car to a tire shop ask them their oppinion, they will mount the tire on the wheel and you can check out if it rubs, and how well it fits the wheel and the wheel well. They'll do just about anything for a sale of 4 tires.

hansjl

Thanks for the responses.

Baby ///M3, I'm not going to lower mine and the 40's would give me a smaller diameter I believe. I'd want all 4 to be the same size so I can rotate them. For the $$$$$ they'll cost, I might as well try to keep them as long as I can. The Michelin Pilot Sports are really at the top of my short list Nice tires!

qtb33, get a friend who has a hand held GPS and check the milage and speed to see houw far, if any, you'll be off. You can adjust from there. I did the GPS when I changed to 17's and it worked well.

Twirl, Although I'm in a large metro area, not all dealers carry all brands, or at least not at the same reasonable discounts. I can play the waiting game for a super sale. I'd like to have a good idea of the size before I commit to a dealer. Honestly, my Toyota dealer has been great and I've used it for my other tire needs. The have really good no-scratch equipment and super balancing. Your idea is good and it's definitely worth a look see. I'm hoping that someone has done this before me.

I almost thought/hoped that Lex Luthor would chime in since he seems to be the resident expert on almost all topic when it comes to SC's... HINT

boobstar

Do a search on google for "tire calculator" it will allow you to plug in different sizes and tell you diameter, circumferance, and speedometer differences between the two tires. Go measure your wheel well and see what the diameter is of that and then get something close but obviously not over what that measurement is.

hansjl

Boobstar,Thanks for the suggestion and the tire calculator is available in the tire forum from The Tire Rack. If you can messure the wheel well and know the tire travel to its highest point in relation to the suspension capabilities and the travel from side to side of the front tires, you're certainly well ahead of where I'm at. I can do the diameter and width calculations very easily and as for the speed, my hand held GPS will let me know where the speed limits are in relation to the tire rotation. Now all I need to know is how big in diameter and width can a tire be before it rubs the wells when turning lock to lock on the steering wheel and rolling over that big bump.

I know I'm not the first that need to figure this out and I know somewhere someone has a really, really big tire on a GS400 17X8 that doesn't rub. Is it a 255/50, 255/55, 250/50, and on and on. I'm not trying to stay within a stock final diameter......

Thanks all for being patient with me And like I said, this isn't a new question and THE MAN will have the answer

Twirl

who said you had to buy the tire? just find the biggest size that will fit and not rub, then bounce and order the make/model you want =).

boobstar

i know on the intellilex sire or whatever it is it also says what tire sizes and wheel sizes are equal to the original. i too am in the same boat as you, i know i want o get an 18 but i would like a bigger tire to help out with the ride and i want to know what i can get away with without rubbing but without looking like a stock wheel/tire combo and all at the same time filling in some gap if possible.

hansjl

Twirl, I would prefer to do business with the person that does the research mounting. With life comes Karma and Karma would cause my rim to get screwed up in the tire removal process and old tire reinstallation. Then there's the cost of rebalancing........

I'd prefer to do it right one/first time

legendary

2 things - every time you upsize the sidewall, you are affecting your odometer reading and your mph
- this car will not need much more than a 245/45/17 if you are trying to fill the wheel wells AND stay within spec.

You mentioned that you do not want to lower the car, but a 1" drop is not very significant, and would give the combo you need.

If you go any taller on sidewall, you are risking a) making the car look dated like a 1985 Town Car and b) affecting the dynamics of the performance characteristics on your vehicle. In addition, you more than likely will rub since the overall diameter will grow almost an inch on 50 series and almost two inches on 55 series. Respectively, your speedo will be off 3.5% and 7.2% slow.

At 60 mph (7.2%) your car will be doing almost 65mph. That is incremental, and you will definitely risk getting a ticket at higher speeds

Edit - if you do a 255/45/17 you will be ok as well

hansjl

Legendary, thanks for the insight. The speedometer being off doesn't really concern me since I used my hand held GPS to verify speed when I changed to the 17's. I do a lot of travel on the interstate and I can translate old speed to new speed, beside, when I’m driving I tend to enjoy second or third place instead of lead since it results in less tickets. Knock on wood; it’s been a long time since I got one. One of the driving factors for wanting to go up in diameter is that I believe the ride will become smoother. I know that when I went to my 17's from my 16's it seem to have an immediate effect on the smoothness of the ride. This could be related to going to speed/rain tires versus my Goodyear all season rubber. Although the diameter of the tire didn’t change, the sidewall height did take a reduction.

Do you think a 255/50 would tuck under the wells? The 1 inch drop would definitely look good but would cost a bit. As it is, I think I’m ready for new struts which will make me dig deeper into my pockets. This is a daily driver that looks good since I just had it repainted, but like a boat it can be a bottomless pit to pour money into. If I start with the money pouring, I think I’ll get a 99 or 00 as a basis for the hole

Thanks again and I’ll look for your thoughts on the 255/50. BTW you do a superb job as Moderator of this forum.