lowering kit bolt size Q
Thread Starter
Burning Brakes
Joined: Dec 2002
Posts: 1,088
Likes: 0
From: Lakeland fl
lowering kit bolt size Q
Anyone know the dimensions of the bolts used to lower the rear? I have an 85 if that matters. I looked briefly and it appears I would want a 1/2 fine thread bolt about 10 inches long, grade 8 of course. Am I right? Thanks.
Melting Slicks
Joined: May 2002
Posts: 3,424
Likes: 1
From: Tucson Az
St. Jude Contributor
Re: lowering kit bolt size Q (SBNova)
I believe you are. Either 1/2 or 5/8 dia. Take along a bushing and see if it goes thru it, I had to open up my new bushings alittle. No big deal. Are you planning on using two ny-lock hex nuts per? I would, just to be sure....
Burning Brakes
Joined: Jul 2003
Posts: 873
Likes: 2
From: Whittier ca
Re: lowering kit bolt size Q (SBNova)
My 91 is 14mm (9/16") x 2.0 pitch x 225mm long (9.0"). Have been looking at local hardware and supply houses for a 10" bolt to drop my car 1.0" with no luck. Still searching
Burning Brakes
Joined: Jul 2002
Posts: 871
Likes: 0
From: Costa Mesa CA
Re: lowering kit bolt size Q (SBNova)
Those long bolts are almost impossible to find. I think the Corvette sellers like Mid-Am have them custom-made and they're still too short.
Find some hardened 9/16" threaded rod and cut to length and use two castle nuts on the top for the bolt head or weld on just one nut.
BIG JIM
[Modified by BIG JIM 54, 6:09 AM 10/7/2003]
Find some hardened 9/16" threaded rod and cut to length and use two castle nuts on the top for the bolt head or weld on just one nut.
BIG JIM
[Modified by BIG JIM 54, 6:09 AM 10/7/2003]
Team Owner
Joined: Jan 2003
Posts: 20,322
Likes: 248
From: Summerland B.C. Canada
Re: lowering kit bolt size Q (subman)
My 91 is 14mm (9/16") x 2.0 pitch x 225mm long (9.0"). Have been looking at local hardware and supply houses for a 10" bolt to drop my car 1.0" with no luck. Still searching
Check them out :cheers:
Burning Brakes
Joined: Jan 2001
Posts: 1,169
Likes: 0
From: Manhattan
Re: lowering kit bolt size Q (AGENT 86)
back in April I spent some time searching for bolts...
"I've been searching for a few weeks now trying to locate a suitable replacement for the rear spring bolts. I finally found a company that carries them. They weren't stocked in my local store, but they're shipping them in for me. http://www.fastenal.com/shoponline/s...p?ProdID=44464
Stock hex head cap screws:
14mm(D) x 2.0 x 230mm(L) grade 9.8 (min tensile strength 130,500psi)
they are equivalent to SAE --
9/16" x 9" grade 6 (min tensile strength 133,000psi) or grade 8 (min tensile strength 150,000psi)
fastenal carries:
Metric socket head cap screws grade 12.9 (min tensile strength 177,000psi) 14mm x 2.0 in lengths 240mm (9.4"), 260mm (10.2") and 280mm (11")
I hope this helps "
I can't remember what size I ended up with, but the threads were not cut very far up the shank of the bolt. I ended up making round spacers from the cutting board I used to lower the front sandwiched between some fender washers.
--steve
"I've been searching for a few weeks now trying to locate a suitable replacement for the rear spring bolts. I finally found a company that carries them. They weren't stocked in my local store, but they're shipping them in for me. http://www.fastenal.com/shoponline/s...p?ProdID=44464
Stock hex head cap screws:
14mm(D) x 2.0 x 230mm(L) grade 9.8 (min tensile strength 130,500psi)
they are equivalent to SAE --
9/16" x 9" grade 6 (min tensile strength 133,000psi) or grade 8 (min tensile strength 150,000psi)
fastenal carries:
Metric socket head cap screws grade 12.9 (min tensile strength 177,000psi) 14mm x 2.0 in lengths 240mm (9.4"), 260mm (10.2") and 280mm (11")
I hope this helps "
I can't remember what size I ended up with, but the threads were not cut very far up the shank of the bolt. I ended up making round spacers from the cutting board I used to lower the front sandwiched between some fender washers.
--steve
Melting Slicks
Joined: Mar 2000
Posts: 2,225
Likes: 0
From: Georgia
Cruise-In I Veteran
Re: lowering kit bolt size Q (SBNova)
If you use Nylocs, cross drill the ends of your bolts & use cotter pins. I did this out of concern for extra safety ..... glad I did. A couple of years after I did the lowering I was checking underneath & found that they Nylocs were "loose". :eek: Not a safety issue with the cotter pins in, tho.
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Safety Car
Joined: Aug 2002
Posts: 4,812
Likes: 1
From: New Albany IN
St. Jude Donor '03-'04-'06-'08-'09
Re: lowering kit bolt size Q (tuband)
Got the kit from Ecklers...put them on and spun the nut up an inch up the bolt, but would like to drop the body another inch. If they are 10" long...then I need to find an 11" rod. I guess it will be mailorder for me too.
Drifting
Joined: Jul 2000
Posts: 1,661
Likes: 4
From: Phoenix, Arizona
Re: lowering kit bolt size Q (SBNova)
The stock one is metric, but a 9/16" bolt is what you need. Someone already said it - use cotter pins or safety wire if you use Nyloc nuts. I use Grade 8 lock nuts of the solid metal variety (slightly distorted threads so there is extra torque & clamping friction) because I think they will last longer. I think they are less likely to be weakened by multiple use and/or the "elements." Check your Yellow Pages for a supplier in the Fasterner industry. Everywhere I've lived, I've found a company that supplies the hardware stores and fabrication industry. They will be the ones to get your 9/16" by 10 or 11 inch bolts and the best locknuts - plus other unique or hard-to-find fasteners - and theri prices will generally be very reasonable. When setting the rear height, remember that setting the nuts at something like "1.5 inches up" on each side may not have you level. I use a jack to unload the spring so the adjustment doesn't place as much load on the threads of the bolt & nuts. Measure ride height after driving to reset the load on the rear. Check alignment when finished. Good luck. :flag
