What offset is better for a Gemini
What offset is better for a Gemini
Does anyone know if
Gestalt 19 inch wheels will these fit a Gemini with a offset of 7.5 or 8
Or will both off sets fit?
Gestalt 19 inch wheels will these fit a Gemini with a offset of 7.5 or 8
Or will both off sets fit?
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You could probably make them fit by pumping the guards although it would most likely not be legal.
In QLD you can only increase the track of the vehicle by 13mm per side.
Standard Gemini offset is 30mm positive so legally you shouldn't be able to go any less than a 17mm positive offset. (The smaller the offset the wider the track of the vehicle.)
I have seen a Gemini with 19's and from a distance it looks like the car is running on the rims. There is virtually no side wall on the tyre.
In QLD you can only increase the track of the vehicle by 13mm per side.
Standard Gemini offset is 30mm positive so legally you shouldn't be able to go any less than a 17mm positive offset. (The smaller the offset the wider the track of the vehicle.)
I have seen a Gemini with 19's and from a distance it looks like the car is running on the rims. There is virtually no side wall on the tyre.
Ok well I have 17s ATM and they got 205/40s on them and they have no sidewal at all but yeah I'll just pump the guards might have to change the lowered springs as well I guess
There's a car on car sales
He wants 40g for it and it's rotory he has the same wheels and they don't look like there hitting the guards so I'll trial fit 19s I guess
There's a car on car sales
He wants 40g for it and it's rotory he has the same wheels and they don't look like there hitting the guards so I'll trial fit 19s I guess
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Just a side note, apart from it seeming like you thought width of the rim was the offset:
Offset for any given rim is relative to the width of the rim you are questioning. There is no 'right' general offset without also knowing the width of the rim.
Offset for any given rim is relative to the width of the rim you are questioning. There is no 'right' general offset without also knowing the width of the rim.
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Correct, so as the rim width changes the offset required to clear between the inside edge of the rim and suspension/steering components will also change. Therefore a 6 inch wide rim with +30mm offset will place the inside rim edge in a different position to a 8 inch wide rim with +30mm offset.
The most important figure is the backspace needed. Hand me that backspace measurement and I'll tell you what offset you need to look for.
The most important figure is the backspace needed. Hand me that backspace measurement and I'll tell you what offset you need to look for.
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to get an idea on how much offset changes due to the width of the tyre.
My 13 inch rims 6.5inches wide have an ofset of 8.
My 18s are 7.5inches wide with an ofset of 40.
They both have the same tyre diametre and sit in the exact same spot in the wheel arch.
So with a 1inch increase in width the ofset has changed by 32mm which is over an inch.
My 13 inch rims 6.5inches wide have an ofset of 8.
My 18s are 7.5inches wide with an ofset of 40.
They both have the same tyre diametre and sit in the exact same spot in the wheel arch.
So with a 1inch increase in width the ofset has changed by 32mm which is over an inch.
MY BUILD viewtopic.php?t=36388 OF THIS s@*tter BELOW
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That is also relative to the diameter of the rim, 17x6 will fit with the +30 offset (same as standard (or is it +35? i can't remember)) a smaller diameter might not (will not) fit if it is much wider than standard because it will foul the shock, (hence the +8 offset on your 13x6.5s)troyrotor wrote:to get an idea on how much offset changes due to the width of the tyre.
My 13 inch rims 6.5inches wide have an ofset of 8.
My 18s are 7.5inches wide with an ofset of 40.
They both have the same tyre diametre and sit in the exact same spot in the wheel arch.
So with a 1inch increase in width the ofset has changed by 32mm which is over an inch.
using the same as standard offset with a wider rim will make both sides of the wheel equally wider, to an extent, the bigger the rim diameter the more likely it is to fit with as close to standard offset.
If it ain't broke, then it DOESNT HAVE ENOUGH FEATURES YET!!!
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It's probably a whole lot easier to work with backspace than offset. You can easily measure backspace by fitting a known wheel rim and getting under the car with a steel rule to measure clearance from the shock to the rim lip. Once you know that distance and know the specs of the wheel you just measured it's easy to select a suitable offset for any other rim width.
Measuring the offset of an unmarked offset rim with known width is easy too. Just lay the rim face down on the ground and grab a length of wood or steel that sits neatly on the opposite rim edges (if it sits on the tyre, shorten it to clear) then measure between the length and the mount face of the rim, that's the backspace. From that figure it's easy to work out what any other rim width/offset combination will clear the shock by (or touch and bend the shock by) as well as to figure out the offset.
Measuring the offset of an unmarked offset rim with known width is easy too. Just lay the rim face down on the ground and grab a length of wood or steel that sits neatly on the opposite rim edges (if it sits on the tyre, shorten it to clear) then measure between the length and the mount face of the rim, that's the backspace. From that figure it's easy to work out what any other rim width/offset combination will clear the shock by (or touch and bend the shock by) as well as to figure out the offset.
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Lets start by using a standard rim...
if we go with a 13"x5" with +35mm offset, backspace is 111mm.
13"x6.5 with an offset of et8 will have a backspace of 103mm. (8mm further away from the shock absorber)
18"x7.5 with an offset of +40mm will have a backspace of 148mm. (37mm closer to the shock absorber) With such a large positive offset number, these are definitely FWD rims and I doubt they would clear the shock absorber when the front wheel is jacked up off the ground.
17"x6" et30 have a backspace of 118 (7mm closer to the shock absorber)
17"x6" et35 have a backspace of 123 (12mm closer to the shock absorber)
A reasonable test is to measure the clearance between the rim edge and the shock absorber when the wheel is fitted at it's fully jacked up point. You should be ideally looking at 10mm clearance, certainly not less than 5mm.
Now it isn't JUST a case of getting offset right for proper suspension part clearance if you want to keep things legal, there is also the question of track change allowance. You can't narrow the track at all so if you want to run FWD high number offset rims you're probably going to find you have reduced the track so it's illegal from that aspect as well as highly likely to be touching the shock absorber.
if we go with a 13"x5" with +35mm offset, backspace is 111mm.
13"x6.5 with an offset of et8 will have a backspace of 103mm. (8mm further away from the shock absorber)
18"x7.5 with an offset of +40mm will have a backspace of 148mm. (37mm closer to the shock absorber) With such a large positive offset number, these are definitely FWD rims and I doubt they would clear the shock absorber when the front wheel is jacked up off the ground.
17"x6" et30 have a backspace of 118 (7mm closer to the shock absorber)
17"x6" et35 have a backspace of 123 (12mm closer to the shock absorber)
A reasonable test is to measure the clearance between the rim edge and the shock absorber when the wheel is fitted at it's fully jacked up point. You should be ideally looking at 10mm clearance, certainly not less than 5mm.
Now it isn't JUST a case of getting offset right for proper suspension part clearance if you want to keep things legal, there is also the question of track change allowance. You can't narrow the track at all so if you want to run FWD high number offset rims you're probably going to find you have reduced the track so it's illegal from that aspect as well as highly likely to be touching the shock absorber.
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