Anyone running 235/45/R18 Eagle RSA tires?

Discussion on wheel & tire issues
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91C02920
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Anyone running 235/45/R18 Eagle RSA tires?

Post by 91C02920 »

I need a tire, and $240ish for a stock size 235/50/R18 seems a bit high.

Walmart has Eagle RSA in 235/45/R18 for $109 each.
https://www.walmart.com/ip/Goodyear-Eag ... 18/5172555" onclick="window.open(this.href);return false;

Looks like a 2.9" circumference difference. Can you set the size in the bcm/anywhere to keep the speedometer accurate?

Would I see much decrease in mpg going to a slightly smaller tire?
I like the RSA tires on the cars I've had them on, but the $240 price for one kind of hurts.
Silversled
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Re: Anyone running 235/45/R18 Eagle RSA tires?

Post by Silversled »

I don't have HP Tuners with me right now but if memory serves, the tire circumference and final gearing adjustments are made in the transmission section. That means a tune.
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v8suprcapric
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Re: Anyone running 235/45/R18 Eagle RSA tires?

Post by v8suprcapric »

This tire comparison chart is awesome:

http://rimsntires.com/specspro.jsp

According to that chart, if you run 235/45R18, when your speedometer reads 60mph your actual speed will be 57.9mph.
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Navy Lifer
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Re: Anyone running 235/45/R18 Eagle RSA tires?

Post by Navy Lifer »

Several things to think about here:

1. Load index

2. Diameter change

3. Speed rating

4. Adequate bead width (wheel/rim) - not saying the 235/45 tire won't work on 8" wheel bead

I'd much rather spend the money on something like this--only slightly more cost than the Goodyear, and in 245/45 size, as long as you're shopping at WalMart:
https://www.walmart.com/ip/Kumho-ECSTA- ... 8099#about" onclick="window.open(this.href);return false;

Kumho:
Load index is higher than OE, XL load range
Diameter is 26.7, still shorter than stock, which is 27.3
Speed rating=W (better than V of the Goodyear)
Bead width range for 245/45 is OK for 8" bead

http://www.tirerack.com/tires/tires.jsp ... csta+4X+II" onclick="window.open(this.href);return false;

The shorter RS-A tire will look "lost" in the body, unless (or even if) the car is lowered, so I'd look at a 245/45-18 option, even though a 255/45-18 gets closer, but really needs an 8.5" bead width.
Pursuit
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Re: Anyone running 235/45/R18 Eagle RSA tires?

Post by Pursuit »

I have switched to the Continental Extreme Contact DWS 06 http://www.tirerack.com/tires/tires.jsp ... toModClar=" onclick="window.open(this.href);return false;
In searching for the above link I found the closeout on the generation before of the same tire..http://www.tirerack.com/tires/tires.jsp ... toModClar=" onclick="window.open(this.href);return false;

They have a smother ride, stick better. I did notice that I gained 1 MPH on my speedo at 70 mph. According to my GPS I am traveling 71 mph when the speedo says 70. I will have to adjust my calibration in the TCM.

Regards
Maurice Sheil

mhsheil@gmail.com

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Navy Lifer
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Re: Anyone running 235/45/R18 Eagle RSA tires?

Post by Navy Lifer »

Makes no sense that the Conti's would have any impact on speed indication--all measure 27.3" diameter, revs per mile range from 761 to 766, so the difference could be measured, but I don't know if it's as much as 1 MPH
Pursuit
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Re: Anyone running 235/45/R18 Eagle RSA tires?

Post by Pursuit »

I thought the same thing. But, it is what it is. And it could be 1/2 of an mph off.. It could be how the two different electronic measuring devices average or round off also. But, with the RSA's, the GPS and speedometer pretty much agreed all of the time.

Regards,

Maurice
Maurice Sheil

mhsheil@gmail.com

2011 Caprice Phantom Black 9C3
2012 Impala 9C1
1995 9C1 Caprice
1996 GMC Sierra C1500
1996 Chevrolet K2500 Extended Cab, long box, 454, 91,000 rust free miles
1974 SJ Grand Prix 455 well optioned with factory moon roof
KERR
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Joined: Wed Nov 12, 2014 4:43 pm

Re: Anyone running 235/45/R18 Eagle RSA tires?

Post by KERR »

you need a TIRE or tires, i would not put one smaller tire on the car.
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