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Discussion Starter #1
I wanted to make a new thread before the other one got bogged down -

Can somone with the 18" CCW fronts measure the actual rim+tire height using 285/30 tires? If somone has already measured their 17" with 275/40 tires id like that measurement as well, if not ill just measure mine tonight when i get home.

Once my car has the coilovers installed, i want to get the car as low as possible to get as much camber as i can out of the front and back, and i have a feeling the 275/40's acting as 4x4 tires are just going to be to tall. I have occasionaly heard the front driver side rub the top of the fender liner on a big bump on the street, although i havent heard it rub on the track yet... and i have all stock suspension settings.


Also keep in mind for those going with a Big Ass Wheel setup, and stock suspension - your car will handle light years better after proper suspension setup (coilovers/alignment etc). With my Big Ass Wheel setup, and stock suspension, i have worn the outside edges of all 4 tires because the stock suspension just isnt setup for tires that wide. My laptimes are still WAY faster then street tires, and im hoping i will get another big improvement in laptimes after the chassis is setup properly.


Ill be in nor cal later this week for the Russell [email protected] point, if anyone is in the area with coilovers id like to have a peak at your car. Ill buy you lunch or something.

-mike
 

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I think you will find a total diameter difference of .9". This would mean you would gain about .45" of clearance before you rub the top of the inner fender liner.

Later, Steve
 

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http://www.smokemup.com/utilities/calc/tire_diameter.cfm

I've had stock suspension with 275/315s for a while, and I didn't think tire temps were that bad. In the rear I think they were pretty even, obviously up front it was all at the outside egde.

Did you remove those 3 screws on the outside of the wheel well? You need to or the tires will rub, especially KDs.
 
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Discussion Starter #4
Grant said:
http://www.smokemup.com/utilities/calc/tire_diameter.cfm

I've had stock suspension with 275/315s for a while, and I didn't think tire temps were that bad. In the rear I think they were pretty even, obviously up front it was all at the outside egde.

Did you remove those 3 screws on the outside of the wheel well? You need to or the tires will rub, especially KDs.

Nope, literally all i did to make the wheels/tires fit was have the rear lips rolled... didnt touch anything else.

Cool site for diameters of the wheels... thats almost an inch of height savings with the 18's.... god damn. Wish i could run 18 fronts for the OTC, id buy a pair.

-mike
 

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fleadh said:



Nope, literally all i did to make the wheels/tires fit was have the rear lips rolled... didnt touch anything else.

Cool site for diameters of the wheels... thats almost an inch of height savings with the 18's.... god damn. Wish i could run 18 fronts for the OTC, id buy a pair.

-mike
BTW Mike... I talked to John Purner last week.... he checked your order... you have 17x9.5's and 17x11.5's. :( I was hoping I wouldn't be the first to test CCW's in 17x10... but....

I'm testing the first 17x10 CCWs on my car soon... I should get them this week.. 17x10s and 17x11.5's. The extra 1/2" of width on the fronts is all on the inner side. (7.25" backspacing compared to your 6.75").


Andi
 
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Discussion Starter #6
Andi,

Why are you going with 17's up front? Why not 18's? Bent rims?
 
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Discussion Starter #8
I'm running the 18x10 CCW in front with a 285 and have been getting some fender liner rub just inside the lip on the left front. My ride height is approx. 1 1/4 lower than stock (in front). Caliper clearance is zip, but John is making some 1.5mm spacers for the front. I notice the lower suspension arms are not horizontal even at my ride height. I've had suspension people tell me suspension geometry works best with horizontal control arms at resting ride height. I assume we're not going to road race at stock ride height (has anyone done this with coilovers/big tires?) because of the roll center being so high. I'm using Kumho tires (315 in rear) and the handling is spectacular compared to the stock wheels. I ran many laps with the rub and didn't lose much rubber, so the rub can't be that bad. I'm going to heat gun the liner where it's rubbing and try to deform it just enough so it won't rub.

Jeff
 

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jkbrauch said:
I've had suspension people tell me suspension geometry works best with horizontal control arms at resting ride height.
That is correct.

I assume we're not going to road race at stock ride height (has anyone done this with coilovers/big tires?) because of the roll center being so high. I'm using Kumho tires (315 in rear) and the handling is spectacular compared to the stock wheels. I ran many laps with the rub and didn't lose much rubber, so the rub can't be that bad. I'm going to heat gun the liner where it's rubbing and try to deform it just enough so it won't rub.

Jeff
I run mine at about a .25" drop. I get tire rub up front if I go any lower even with the stock bumpstops and 750 lbs. springs. The problem with rubbing isn't tire wear as much as that if you rub the top of the fender long enough you'll wear through that plastic piece behind the fender liner and start rubbing a wire harness that runs up there. Bad things will happen quickly once that starts. In a video I'll post the URL for shortly, you can hear what my car sounded like with a ~1" drop. It would rub on just about every corner and/or bump.

Eric
 
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Discussion Starter #10
Eric said:


That is correct.



I run mine at about a .25" drop. I get tire rub up front if I go any lower even with the stock bumpstops and 750 lbs. springs. The problem with rubbing isn't tire wear as much as that if you rub the top of the fender long enough you'll wear through that plastic piece behind the fender liner and start rubbing a wire harness that runs up there. Bad things will happen quickly once that starts. In a video I'll post the URL for shortly, you can hear what my car sounded like with a ~1" drop. It would rub on just about every corner and/or bump.

Eric


Eric,

You get that rub with 275/40/17 fronts rite? Or is that with 18's?

What wiring harness is it that rubs? And have you looked into relocating it?

-mike
 

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fleadh said:


Eric,

You get that rub with 275/40/17 fronts rite? Or is that with 18's?

What wiring harness is it that rubs? And have you looked into relocating it?

-mike
Correct. I have 275/40-17s up front. I have not looked into relocating the harness because IMO, lowering the car much isn't a good idea. There just isn't enough suspension travel up front before the tire hits something.

Eric
 
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Discussion Starter #12
Eric - Thanks for the input. What ride height are you running in the rear?

Jeff
 

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jkbrauch said:
Eric - Thanks for the input. What ride height are you running in the rear?

Jeff
About the same drop as in the front. I didn't want to change the relative f/r drop. I haven't really experiemented with different rear ride heights though.

Eric
 
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Discussion Starter #14
Eric - I notice to level the lower suspension arms in the rear, it has to be dropped more than the front. I guess they were looking at this car carrying 4 people alot of the time. Go figure. Did you notice any handling changes when you raised the car for tire clearance?? I figure with a smaller diameter 18 I can maybe get away with a 3/4" drop - I'll experiment and let you know.

Thanks again, Jeff
 

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jkbrauch said:
Eric - I notice to level the lower suspension arms in the rear, it has to be dropped more than the front. I guess they were looking at this car carrying 4 people alot of the time. Go figure. Did you notice any handling changes when you raised the car for tire clearance?? I figure with a smaller diameter 18 I can maybe get away with a 3/4" drop - I'll experiment and let you know.

Thanks again, Jeff
If I remember correctly, my car was only .25" higher in the back with the stock springs. It's worth experimenting with. I just haven't been motivated to do it. Running the 18"s up front should allow for more drop since it's a considerably shorter package than with the 17"s.

Eric
 

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jkbrauch said:
I've had suspension people tell me suspension geometry works best with horizontal control arms at resting ride height
Hmm, I didn't know that.

So do people use the stock bumpstops in the rear?
 
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Discussion Starter #17
Grant said:


Hmm, I didn't know that.

So do people use the stock bumpstops in the rear?
I don't know - I know I'm using whatever HKS fits to their coilover setup.
 
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