adapter size
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7th Gear
Joined: Jan 2015
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adapter size
I have searched hundreds of threads but now confused ! I have a 1986 c4 and I just bought a set of 2009 c6 split spoke wheels they are 18 fount and 19 rear just need to know what size of adapters I need ? thanks for any help
Safety Car
Joined: Aug 2009
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From: Melbourne, Victoria, Australia
Note having 18 inch diameter front and 19 inch diameter rear can cause problems with the ABS, they sense front and rear wheel speed any mismatch can case a problem.
http://www.ebay.com/itm/4-WHEEL-SPACERS-ADAPTERS-USE-5X100-WHEELS-ON-5X120-CAR-1-INCH-THICK-25MM-/231368345667?pt=Motors_Car_Truck_Parts_Accessories&hash=item35dea0c843
Last edited by gerardvg; Mar 2, 2015 at 08:39 PM.
Team Owner
Joined: Sep 2003
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30mm (1.25") for the fronts duplicates the wheel/tire placement if your '86 had 9.5" originally, this would be a desired placement I'd think regardless. 1" works also.
40mm (1.5") for the rears I'd think offer a good fit for the rears.
I assumed the C6 wheels had 56mm and 79mm offsets but you need to confirm that and it should be cast in the wheels. If they're "replica" wheels all bets are off because they're likely done in a few different offsets.
Tire sizes is a 'pickem - your decision, but like mentioned you should attempt to keep diameters very close.
I rounded thickness to what's generally inexpensive. 35mm (1 3/8") for the rears if they were priced competitively might be the ideal buy.
*** I forgot to mention the bolt circle for your reference but you want to be looking for 5 X 4 3/4" (120.65mm). You do NOT want 120mm , it's 120.65mm if you're shopping Metric.
40mm (1.5") for the rears I'd think offer a good fit for the rears.
I assumed the C6 wheels had 56mm and 79mm offsets but you need to confirm that and it should be cast in the wheels. If they're "replica" wheels all bets are off because they're likely done in a few different offsets.
Tire sizes is a 'pickem - your decision, but like mentioned you should attempt to keep diameters very close.
I rounded thickness to what's generally inexpensive. 35mm (1 3/8") for the rears if they were priced competitively might be the ideal buy.
*** I forgot to mention the bolt circle for your reference but you want to be looking for 5 X 4 3/4" (120.65mm). You do NOT want 120mm , it's 120.65mm if you're shopping Metric.
Last edited by WVZR-1; Mar 3, 2015 at 08:30 AM.
Team Owner
Joined: Sep 2003
Posts: 25,361
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Hi the wheels fit the 88-96 corvettes that have the 54 mmm offset, the 84-87 have 38mm offset (3/4 inch) the adapters i used to fit the 88-96 corvette wheels on 84-87 Corvette are 1 inch thick.
Note having 18 inch diameter front and 19 inch diameter rear can cause problems with the ABS, they sense front and rear wheel speed any mismatch can case a problem.
4 Wheel Spacers Adapters Use 5x100 Wheels on 5x120 Car 1" inch Thick 25mm | eBay
Note having 18 inch diameter front and 19 inch diameter rear can cause problems with the ABS, they sense front and rear wheel speed any mismatch can case a problem.
4 Wheel Spacers Adapters Use 5x100 Wheels on 5x120 Car 1" inch Thick 25mm | eBay
Le Mans Master
Joined: Nov 2006
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From: Greenwood Indiana
2021 C4 of the Year - Modified Finalist
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I put the C6 5-spokes on my 94. No spacer on the front, but I had to put a 1" on the back of mine to keep from rubbing the brake line.
1" spacers are required on all 4 wheels to put later C4 wheels on an early model C4, therefore, shouldn't you add additional inch to the back wheels to clear everything?
I think he needs a set of 1" adapters for the front and 2" for the back. I could be wrong, because I don't know the offsets for those "split-spoke" wheels.
You could always take them off your car and measure the back-spacing of your original wheels and of the new C6s. Whatever the difference is, that's the sizes you need to get.
1" spacers are required on all 4 wheels to put later C4 wheels on an early model C4, therefore, shouldn't you add additional inch to the back wheels to clear everything?
I think he needs a set of 1" adapters for the front and 2" for the back. I could be wrong, because I don't know the offsets for those "split-spoke" wheels.
You could always take them off your car and measure the back-spacing of your original wheels and of the new C6s. Whatever the difference is, that's the sizes you need to get.
Le Mans Master
Joined: Nov 2006
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From: Greenwood Indiana
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Le Mans Master
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From: Greenwood Indiana
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I think the stock 84-87 wheel offset was 36mm, so the difference on your new ones are 20mm (frt) and 43mm (rear).
Adapters would be 20mm frt = 3/4" to 1", 43mm Rears= 1.5" to 1.75".
Bolt circle is 4.75" or (metric) 120.7mm.
Adapters would be 20mm frt = 3/4" to 1", 43mm Rears= 1.5" to 1.75".
Bolt circle is 4.75" or (metric) 120.7mm.