adapter thickness
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
You will need 3/4" (18mm) adapters to mount the later wheels to an 84-87 car so the newer wheels will sit in the same position as the early wheels.
Some vendors offers adapters for around $200 a pair
and you can find them on flea-bay for much cheaper. Are they the same quality? Hard to say. Most vendors that offer the cheap adapters don't provide any specs on the type or strength of the aluminum stock or the type of studs used.
Some vendors offers adapters for around $200 a pair
and you can find them on flea-bay for much cheaper. Are they the same quality? Hard to say. Most vendors that offer the cheap adapters don't provide any specs on the type or strength of the aluminum stock or the type of studs used.
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
You will need 3/4" (18mm) adapters to mount the later wheels to an 84-87 car so the newer wheels will sit in the same position as the early wheels.
Most vendors that offer the cheap adapters don't provide any specs on the type or strength of the aluminum stock or the type of studs used.
Most vendors that offer the cheap adapters don't provide any specs on the type or strength of the aluminum stock or the type of studs used.
budget adapters may be 2xxx series alum alloy (esp china mfr) that is less than half as strong as heat treated 6xxx alum... i suggest you buy top quality adapters from VB&P, even a 'minor event' with a broken adapter will rip a fender off, spoil your day -- major event may result in loss of control and catastrophic outcome.
my 86 adapters are 1.25'' thick, from VB&P... studs in mine are 1/2'' , larger than oem 12mm (oem studs seat in a steel hub, adapter studs seat in alum, bigger is better in this case)
Le Mans Master
Joined: Oct 2007
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From: Akron Ohio
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St. Jude Donor '09-'10-'11
Do you have wheels or are you looking to buy? I have some Torq Thrust M wheels that would only need a 1/4" spacer to work on your '85.
Le Mans Master
Joined: May 2006
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From: Irvine Ca
Here is the spacing on an '84 with '99 Mags.
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
my adapters are held on the hub by 'old' style mag wheel nuts with long shanks...these load the stud close to the hub, greatly reducing 'moment' on the stud vs 'cone' lugs...the 'old mag' lugs also must have clearance between lug/adapter hole to allow assembly and this clearance (o.010'' on mine IIRC) allows 'perfect' centering using a dial indicator...what type do yours have ???
nuts holding the wheel to the adapter should follow wheel design (cone for most oem wheels)
NOTE:...all 'cone' type mounting nuts that bear on aluminum should be BULGE ACORN type to prevent damage/failure that the exposed corners of 'acorn' nuts will cause.
Thread Starter
Advanced
Joined: Jan 2010
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From: ft myers florida
well my boss bought himself a gorgeous 88 with z52,boy this one is real clean,im going to make him join the forum or i wont work on it
anyway it has AFS zr1 wheels and hes going to give me the stock 17x9.5s
with perfect goodyears on it by the way
anyway it has AFS zr1 wheels and hes going to give me the stock 17x9.5s with perfect goodyears on it by the way
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Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
I have a set of 3/4" adapters that I can't use. The acorn nuts that fasten the adapter to the hub interfere with the aftermarket wheels I have. They worked great to put 88 factory vette wheels on my 85.
Anyone know where I can find 3/4" adapters that have flush lug nuts?
Anyone know where I can find 3/4" adapters that have flush lug nuts?
Thread Starter
Advanced
Joined: Jan 2010
Posts: 95
Likes: 0
From: ft myers florida
I have a set of 3/4" adapters that I can't use. The acorn nuts that fasten the adapter to the hub interfere with the aftermarket wheels I have. They worked great to put 88 factory vette wheels on my 85.
Anyone know where I can find 3/4" adapters that have flush lug nuts?
Anyone know where I can find 3/4" adapters that have flush lug nuts?
Last edited by 1stL98; Mar 1, 2010 at 09:35 PM.
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Thread Starter
Advanced
Joined: Jan 2010
Posts: 95
Likes: 0
From: ft myers florida
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
I have no idea who the manufacturer is. They were on the car when I got it. They are several years old and knowing the previous owner, I doubt seriously they came from eBay. He got most of his parts from Mid America or Summit. They are aluminum and polish up nicely.
Le Mans Master
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
got me cornfused...''new acorn lugs underneath''??
my adapters are held on the hub by 'old' style mag wheel nuts with long shanks...these load the stud close to the hub, greatly reducing 'moment' on the stud vs 'cone' lugs...the 'old mag' lugs also must have clearance between lug/adapter hole to allow assembly and this clearance (o.010'' on mine IIRC) allows 'perfect' centering using a dial indicator...what type do yours have ???
nuts holding the wheel to the adapter should follow wheel design (cone for most oem wheels)
NOTE:...all 'cone' type mounting nuts that bear on aluminum should be BULGE ACORN type to prevent damage/failure that the exposed corners of 'acorn' nuts will cause.
my adapters are held on the hub by 'old' style mag wheel nuts with long shanks...these load the stud close to the hub, greatly reducing 'moment' on the stud vs 'cone' lugs...the 'old mag' lugs also must have clearance between lug/adapter hole to allow assembly and this clearance (o.010'' on mine IIRC) allows 'perfect' centering using a dial indicator...what type do yours have ???
nuts holding the wheel to the adapter should follow wheel design (cone for most oem wheels)
NOTE:...all 'cone' type mounting nuts that bear on aluminum should be BULGE ACORN type to prevent damage/failure that the exposed corners of 'acorn' nuts will cause.
"Open Lug nuts. Part #5445-44, 12mm- 1.50 RH thread size"
Those hold the adapter to the hub and luckily the Lugs aren't as long as the 1.25 Spacer.
Then...I had to buy:
"Acorn Lug Nuts, part #30-1711, 1/2 RH thread size"
So the open lugs are really short and stubby and they tuck right into the adapter, whereas the Acorn ones are nice and chrome.
Race Director
Joined: Nov 2003
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From: Overland Park Kansas
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Or buy wheels with a little bit of "dish" on the rim -- like some of us later model vette owners wish we could do.
