18x8.5 with a 38 offset
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From: Phoenix
18x8.5 with a 38 offset
Found a set of wheels I can live with for OK money.. They are Konigs from discount and will accept the pressure sensor.
The Discount computer is saying the with 8.5 wide, need to maintain 42 or more offset to avoid tire rub.
I know that a bunch of you are running 18x9s or 19x9s or wider with a 35-40 offset.
So whats the reall deal, is an 18x8.5 with a 38 offset and a 245/40R18 goona rub front or back with stocj height suspension??
Response appreciated as I would like to order the wheels on Wed. Tomorrow.
tried to insert pic of the wheel. hope it works. Thank you very much
[IMG]www.konigwheels.com/catalog_product_details.cfm?CategoryID=1&ss_id=419[/IMG]
The Discount computer is saying the with 8.5 wide, need to maintain 42 or more offset to avoid tire rub.
I know that a bunch of you are running 18x9s or 19x9s or wider with a 35-40 offset.
So whats the reall deal, is an 18x8.5 with a 38 offset and a 245/40R18 goona rub front or back with stocj height suspension??
Response appreciated as I would like to order the wheels on Wed. Tomorrow.
tried to insert pic of the wheel. hope it works. Thank you very much
[IMG]www.konigwheels.com/catalog_product_details.cfm?CategoryID=1&ss_id=419[/IMG]
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From: Houston
iammemares,
I have 245/40-18's on 18X8.5 that have a 45mm offset. If mine are 45mm and the ones you want to get are 38mm, that difference is 7mm. 7mm is a little over a quarter of an inch.
I can comfortably say that there is at least quarter of an inch of clearance between the outside of the tire and the fender currently on my vehicle in the front wheel wells. I would give yourself a 95% or better chance of those wheels fitting without issues and it should look very very nice with the tire going almost all the way out to the fender.
In the back you will have even more clearance to work with. (In the back have 275/35-18's on 18X9.5 with a 42 offset
)
-Mr. Wigggles
I have 245/40-18's on 18X8.5 that have a 45mm offset. If mine are 45mm and the ones you want to get are 38mm, that difference is 7mm. 7mm is a little over a quarter of an inch.
I can comfortably say that there is at least quarter of an inch of clearance between the outside of the tire and the fender currently on my vehicle in the front wheel wells. I would give yourself a 95% or better chance of those wheels fitting without issues and it should look very very nice with the tire going almost all the way out to the fender.
In the back you will have even more clearance to work with. (In the back have 275/35-18's on 18X9.5 with a 42 offset
)-Mr. Wigggles
Last edited by MrWigggles; Apr 12, 2006 at 01:32 AM.
Shootin' from the hip
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From: Sydney, Australia
I am running 18x8.5 with 38 offset (Enkei RP03's) and 235/40R18 rubber (Michelin PS2's) and I haven't had any rubbing problems.
Before you buy 245's, consider 235's. I'm not sure about the availability and cost comparison in the US but I reckon the slightly lesser width sharpens turn in and reduces tyre squirm (a little like the 225's on the stock rim). I appreciate others may have a different view and prefer the widest rubber they can get away with but let's face it, the chassis is hardly overwhelmed with power and I believe it's important to try and keep the sharpness that Mazda's engineers dialled into the car.
Before you buy 245's, consider 235's. I'm not sure about the availability and cost comparison in the US but I reckon the slightly lesser width sharpens turn in and reduces tyre squirm (a little like the 225's on the stock rim). I appreciate others may have a different view and prefer the widest rubber they can get away with but let's face it, the chassis is hardly overwhelmed with power and I believe it's important to try and keep the sharpness that Mazda's engineers dialled into the car.
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From: Houston
The problem with the 235/40 is the sidewall is shorter and the diameter is smaller (if there is a perceptable difference in squirm, that would be the cause.)
This means it will ride a little harsher and will add another 1% or so error to the speedo (The RX-8 already reads at least 2 MPH high at 60MPH. With the 235/40 it will be 3 MPH)
The differences between the 235/40 and 245/40 tires are going to be small, but those are the differences.
-Mr. Wigggles
This means it will ride a little harsher and will add another 1% or so error to the speedo (The RX-8 already reads at least 2 MPH high at 60MPH. With the 235/40 it will be 3 MPH)
The differences between the 235/40 and 245/40 tires are going to be small, but those are the differences.
-Mr. Wigggles
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From: Phoenix
Thanks
Thank you for the feedback.
I also appreciate the thought on the 235s. I also believe a 235 would do well. The tires I want to run is the M/L Pilot Sport Cup. This is only available in a 235/35. This would be seriously short, about 6 MM overall. And I agree with you assesment that a 235 is probably enough tire and a good balance for an otherwise stock RX.
The focus on performance is why I am staying with an 18 and not going with monster tires that just increase rolling resistance and unsprung mass.
Looks like I am gonna give the 38 offset a go.
I also appreciate the thought on the 235s. I also believe a 235 would do well. The tires I want to run is the M/L Pilot Sport Cup. This is only available in a 235/35. This would be seriously short, about 6 MM overall. And I agree with you assesment that a 235 is probably enough tire and a good balance for an otherwise stock RX.
The focus on performance is why I am staying with an 18 and not going with monster tires that just increase rolling resistance and unsprung mass.
Looks like I am gonna give the 38 offset a go.
Shootin' from the hip
Joined: Apr 2005
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From: Sydney, Australia
Originally Posted by MrWigggles
The problem with the 235/40 is the sidewall is shorter and the diameter is smaller (if there is a perceptable difference in squirm, that would be the cause.)
This means it will ride a little harsher and will add another 1% or so error to the speedo (The RX-8 already reads at least 2 MPH high at 60MPH. With the 235/40 it will be 3 MPH)
The differences between the 235/40 and 245/40 tires are going to be small, but those are the differences.
-Mr. Wigggles
This means it will ride a little harsher and will add another 1% or so error to the speedo (The RX-8 already reads at least 2 MPH high at 60MPH. With the 235/40 it will be 3 MPH)
The differences between the 235/40 and 245/40 tires are going to be small, but those are the differences.
-Mr. Wigggles
The speedo error I can live with. If anything, it builds a little more safety margin in when you're being careful NOT to speed (e.g. school zones, etc).
As for ride, I've actually found the ride improved. However, that may be due to the ride difference between the OEM Bridgestones and the Michelin PS2's I've fitted rather than any diameter change. Can't say enough about them - great tyre (oops, sorry - tire
).
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From: Sydney, Australia
Originally Posted by 09Factor
Nice looking rims, but ouch 30 Lbs!
I thought my Falkens were heavy at 23
I thought my Falkens were heavy at 23
Why add 50% weight for looks?? Personal choice I guess.
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Joined: Feb 2006
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From: Central California
Originally Posted by Revolver
I am running 18x8.5 with 38 offset (Enkei RP03's) and 235/40R18 rubber (Michelin PS2's) and I haven't had any rubbing problems.
Before you buy 245's, consider 235's. I'm not sure about the availability and cost comparison in the US but I reckon the slightly lesser width sharpens turn in and reduces tyre squirm (a little like the 225's on the stock rim). I appreciate others may have a different view and prefer the widest rubber they can get away with but let's face it, the chassis is hardly overwhelmed with power and I believe it's important to try and keep the sharpness that Mazda's engineers dialled into the car.
Before you buy 245's, consider 235's. I'm not sure about the availability and cost comparison in the US but I reckon the slightly lesser width sharpens turn in and reduces tyre squirm (a little like the 225's on the stock rim). I appreciate others may have a different view and prefer the widest rubber they can get away with but let's face it, the chassis is hardly overwhelmed with power and I believe it's important to try and keep the sharpness that Mazda's engineers dialled into the car.
Very intelligent response. Thanks.
Jeffrey
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