Kerrmudgeon

Do you have any hints, or what tho look out for? Any videos? Thanks.

Mooser

Hmmmm

You'll need to remove rear swaybar brackets if you have them to get the bolts in/out.

Avoid using bolts that hang down farther than the rim, if you get a flat you don't want that bolt to touch the ground.

The drop isn't directly the same as the change in bolt length, about 3/4 drop to 1" length or there abouts.

The longer bolts are easier to hook the spring to

Good time to put new cushions on

HIH
Mooser

ignatz

Don't let the spring get anywhere near the tire! It's way worse than just worrying about a flat. If the spring catches the rubber you're gonna crash!

Mike Ward

Jack at the outermost edge of the spring to relieve the tension before loosening the bolt. Clamp a piece of wood inboard to prevent the jack from slipping along the spring.

TheSkunkWorks

Long spring bolts are SOP for lowering the rear. If 8" bolts aren't long enough, you may have an overly arched spring. Use quality nylocks.


The more sidewall there is (as is the case with smaller diameter rims), the more severely will tires distort under high lateral loads, and by a good bit more than you might think.




PS. Always admire your taste in vintage pinups.

7T1vette

The longer bolts allow the "box" (rear) end of the trailing arm to move farther UP...not allow the spring to go much (if at all) lower. The wheels stay where they are, so the spindles are in the same place; but the trailing arms can rotate around the spindles. So, with longer bolts, the rear of the T/A's moves UP and the front end of the T/A's moves downward. Since the front end of the T/A's is mounted to the frame/body, the body moves DOWN proprotionally. And, as the rear of the body moves DOWN (what you are trying to accomplish), the differential will also move down...but only as much as some additional loading at the rear will cause the spring to compress. The outer ends of the spring should not really change position at all.

Now, that's my understanding of how the "longer bolt" causes the rear end to drop. I haven't done it yet, because I just installed Bilstein HD's on the car and the rear is only now beyond the height I'm comfortable with. But, I've been thinking about this modification prior to executing it. The 'mechanics' of it is not as simple as it seems.

Where is the best place to buy the longer bolts? I'm ready to place my order.

Rebelrob

I purchased some 10 inch bolts Grade 8 I think from VBP. These will pull the rear down. 8 inch bolts did not seem to make a lot of difference.

Roco71

I did this about two years ago with 8inch bolts. I cant remember all the details but it was not difficult. I did one side at a time compressing the spring with a floor jack. One tip that I wish I would have done is paint the hardware (washers) on the bolt kit first. After two years mine now appear rusty looking.

Frankenvette

Pic with 10" bolts. Close to tire but even after auto crossing the bolts have never rubbed the tire. I would actually like the bolts to be a little shorter but have not taken the time to mess with it.

7T1vette

Just use a die-grinder with a cut-off wheel to lop the [excess] end of that bolt off....

PatsLs1vette

i run vb&p 10 inch bolts but i also shortened my leaf spring to pull the bolts away from sidewall of tire.

TheSkunkWorks

To clarify, adjusting the length of the bolt (at the nut) does move the spring up or down relative to the ground along with the chassis, which means it does change position relative to the tires and bearing carrier end of the TAs. That's what puts tires (depending on their size) on stock diameter rims in jeopardy of touching the spring when lowering. The remedy for this is a shortened main leaf (available if you know to ask). Adjusting rear height does not change the load on or arch of the spring.


I won't belabor the point here, but do bear in mind when lowering rear, tho it certainly has benefits, that it's very easy to unintentionally increase adverse toe-steer inherent to the C2/C3 IRS by doing so. For those who enjoy spirited driving or AX/RR tracking, do your homework before taking this too far without considering the possibility.


.

69firebird

Where is anyone getting these bolts? I see VB&P isn't stocking them any more, I checked with Fastenal and Grainger and neither of them have it. Where can they be found?

Frankenvette

Try checking with your local hardware store and see if they can special order them from their supplier... typically a company called Hillman.

Frankenvette

Can you elaborate a little on what you did? How far in did you relocate the bolt holes? How much did you shorten your spring? My friend is a welder and could modify my spring a little shorter.

69firebird

Hillman doesn't even have those listed on their website.

69firebird

So I've heard of other folks using these, anyone have any experience with them? They dont look grade 8, so not sure what their relative strength is.

http://www.mamotorworks.com/corvette...-190-1085.html

SuperBuickGuy

I put 10" ones from mamotorsports.com on my 75. My observations: 1 - I did jack the spring up on one side to get the bolt out (I have a lift, so it's a bit different then on jackstands, I would guess).; 2 - I moved the bracket to the inside of the bolt hole and did heat and bend the sway bar.... it works


3 - it does change the camber of the rear wheel - and whoever said above - it does get interesting if you don't check/fix it before you drive it.... mine went for -1* to -3 1/2*. That said, it's really easy to change the camber, so just do it (use a level and a tape measure to check the alignment, then reset it once you've put the bolt it), do remember that you need to move the car a bit to get the suspension to settle before you call your alignment good (my mistake)

mark6669

I have done this many times bought some from ecklers about 2 mo ago.
Mark

Mike Ward

Never seen link bolts assembled like that before..........(?)