OHSIXX

What is envolved in this procedure? How long does it take? Is it relatively easy to do? :confused:


[Modified by OHSIXX, 1:53 PM 10/16/2003]

Brettmc

Very easy...took me about an hour and that was with a lot of fussing with jacking the spring. Only thing, after puttin in longer bolts, my rear ride height did not decrease!! PO must have put on a gargantua spring.

Brett :thumbs:

69 N.O.X. RATT

All you do is lower the nut on the bolt that goes through the spring and the rear will lower, make sure to check the camber when you are done.

Don't go too low with the nut or it will fall off.


[Modified by 69 N.O.X. RATT, 7:24 PM 10/16/2003]

JJ Deuce

:iagree: , but put the car on jackstands, and use a jack to support the spring. If you have a composite spring, there's a metal lip at the end where you can put the jack. On a steel spring, use a c-clamp, or vise grips to keep the jack from sliding up the spring. I replaced the stock bolts on my car with Grade 8 9/16" x 8". It lowered the car about 1-1/2", but now I'm about to install the adjustable strut rods to fix my camber angle.

FeedVaal

8" weren't enough to get my rear lower with a new 9leaf standard so I opted for 5/8 x 9 which required enlarging the hole in the swing arm and the bushings. I can still go a little lower but at some point the tire is going to make contact with the spring. Most folks can get by with 8" but some folks need 9" in the rear. :lolg:

Chuck Harmon

Installing a longer bolt is pretty simple. Place the jack under the far end of the spring and raise until the spring is horizontal to the ground. This help the spring from sliding off the jack. Keep hands and fingers clear in the event the jack fails. Also use jack stands to block the rest of the car.

Two concerns with longer spring bolts:

1) If the lower end of the bolt is at or below the rim, you will drag the spring bolt if you have a flat.

2) If the clearance between the tire and the end of the spring is not enough, you will rub the sidewalls on turns and risk a blowout with the critical outside rear tire on a curve. Tires flex more than you may think. Especially if you are running below 32 psi.

Chuck

The Dude

Whatchoo talkin' 'bout, Willis?

:lol:

9" in the rear...

Doug70vert

I went with 10" bolts which are too long for a stock front ride height. I tightened the nuts until the ride height looked right and then did some slow speed testing. I checked the tire clearence and had a slight rub. after some tweaking the ride height is perfect and hard low speed cornering doesn't rub.

9" bolts would probably work fine but I may want to go lower when I change to different wheel tire combo.

GaryS

The GM Service Manual for your car gives a very good account on how to do this. If you don't own one, you should. If you want one, go over to http://www.ncrs.org and click on their store logo. The good thing about the GM manual is that it is specific for your car and gives steps as well as safety procedures.

With that note, it is fairly easy to do and only involves a little bit of grunt work. Safety is the biggest issue here because of the energy that a spring contains. It CAN kill you if you don't follow specific procedures.
Gary

GUSTO14

I changed my rear spring out for a VB fiberglass spring in '91. I was autocrossing regularly in Hawaii and wanted to lower it as much as I could. I tried the 10" bolts and had 1" clearance between the tire sidewall and the spring. After a couple of autocrosses, I notice a slight rub mark on the sidewalls, nothing to worry about... I thought. Next race I leaned on it a little to much and it ripped the entire sidewall out of the left rear tire before I got it stopped.

After I spent $450 replacing the two rear tires (255/60-15 Gatorbacks) I decided to use the 8" bolts and switch to "cheaper" Hoosiers for autocrossing! 12 years later and no problems.

As long as the spring doesn't go below the bottom of the rim you'll have no problems. Otherwise it only a matter of time before it will get your attention... real fast!

GUSTO

Jvette73

When I lowered mine with longer bolts it was the spring cushion washer that rubbed the inner sidewall. I could tell by the scuff marks left on the tire after a test ride. The washer that was on there was quite large in outside diameter. So I just changed them out for a smaller diameter washer. Then took it for another test drive with lower tire pressure and cornered hard both ways in an attempt to push the extreem. The smaller washers solved the problem. I cant get em to hit the tire no matter how har I try.