Fitting Coil-overs
Instructor
Joined: Aug 2015
Posts: 125
Likes: 22
From: Colorado
Everything is assembled (excluding the swaybar links) wheels on and dropped it on the ground.
next problem, the 10" spring is too long. with the coilover adjusters all the way down the chassis heights are 6" in the front (or 27" eye-brow height)
it was 5 & 5/8" with the z51 spring in.
Probably should have gone with a 9" x 550 lb spring.
The installed height of the 10" 600lb spring is 8"
spoke to guru jim, he says bring the springs in and he will try and 'scragg' them down an inch.
thats cool I dont mind jacking it up and taking everything apart again !
next problem, the 10" spring is too long. with the coilover adjusters all the way down the chassis heights are 6" in the front (or 27" eye-brow height)
it was 5 & 5/8" with the z51 spring in.
Probably should have gone with a 9" x 550 lb spring.
The installed height of the 10" 600lb spring is 8"
spoke to guru jim, he says bring the springs in and he will try and 'scragg' them down an inch.
thats cool I dont mind jacking it up and taking everything apart again !
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
Your thread is great with a lot of good info. It seems to me your going to have to cut off your stock shock tower and raise it 2inches or get a smaller Coilover? If you cut your spring it wont sit in the Cups evenly? I'm currently doing this to my 92 and should be done today? I will post a thread later. On my trial fitting my wheel lip was 24 3/4 inch from the ground. Also move your factory Sway bar bracket ahead/forward 3/4inch and you won't need the those links on your Sway Bar. Good luck.
Show us pictures of yours when done !
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
While Im waiting for the springs to be reset I have made up some brackets (using angle steel) and started with the swaybar fitup.
I have used a 10 mm alloy shim to get some height due to the swaybar being turned up slightly to miss the coilover spring.
I have used a 10 mm alloy shim to get some height due to the swaybar being turned up slightly to miss the coilover spring.
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
http://www.autospeed.com/cms/article...rings&A=112276
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
while at the swaybar I need to clearance the poly bushings, with the powdercoat on the front bar is 31 mm and when its bolted up its actually too tight to move without the use of a hammer !
honing out the bushing with a master cylinder hone in a drill,
and using a 30 mm piece of bar with paint on it, to size it up,
bolted back on with some fresh Energy Suspension grease and it rotates but is still tight.
honing out the bushing with a master cylinder hone in a drill,
and using a 30 mm piece of bar with paint on it, to size it up,
bolted back on with some fresh Energy Suspension grease and it rotates but is still tight.
Le Mans Master
Joined: Aug 2015
Posts: 6,125
Likes: 2,000
From: St. Charles MO
the springs are going back to the manufacturer, Industrial springs, to be reset, which involves the spring going back thru the treating process and being scragged to make them shorter. the spring rate will remain the same.
http://www.autospeed.com/cms/article...rings&A=112276
http://www.autospeed.com/cms/article...rings&A=112276
It might make a lot more sense to order another pair of springs that had an inch or two shorter free length with a similar coil spacing to what you have now. After all, the beauty of coilovers is the ease of spring changes.
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Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
I wouldn't worry about the rate or heat treating being compromised (let's assume the manufacturer knows what they're doing), but I would worry about losing a lot of compression travel due to coil bind. Before you do this, let me suggest that you figure out how much the current springs can be compressed prior to encountering coil bind. Let's say it's currently 3" of compression to bind. Resetting them an inch shorter will leave you with 2". If your installed height takes away an inch, you're left with only an inch of compression travel in the spring (it will be more at the wheel, but less than 2" - I can't recall the motion ratio of the dampers in a C4, but I want to say it's around 0.7:1).
It might make a lot more sense to order another pair of springs that had an inch or two shorter free length with a similar coil spacing to what you have now. After all, the beauty of coilovers is the ease of spring changes.
It might make a lot more sense to order another pair of springs that had an inch or two shorter free length with a similar coil spacing to what you have now. After all, the beauty of coilovers is the ease of spring changes.
Le Mans Master
Joined: Aug 2015
Posts: 6,125
Likes: 2,000
From: St. Charles MO
I took some measurements with the car on the ground and suspension compressed, then took the springs and measurements to jim, he did the calculation to work out what the free length needs to be changed to , to obtain the compressed height (taking into account motion ratio, front end weight etc etc). He has sent the springs to industrial springs with the calculation yesterday. He said coil bind shouldnt be a problem, there is only going to be about 2" of compression travel with my setup.
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
I decided to buy a pair of 9" x 450 lb springs for street use. (the 600 pounders can be the track springs !)
I did a test fit with the 450 lb spring and the coil over assembly just about fell in !
I cant believe how much easier the 450 lb spring is to fit in.
Those bloody 600 lb springs have caused me so much grief, but at least I have done the hard work to get them in and I can sway between them when I need.
I did a test fit with the 450 lb spring and the coil over assembly just about fell in !
I cant believe how much easier the 450 lb spring is to fit in.
Those bloody 600 lb springs have caused me so much grief, but at least I have done the hard work to get them in and I can sway between them when I need.
Instructor
Joined: Aug 2015
Posts: 125
Likes: 22
From: Colorado
Excellent choice on spring. Drive it with those 450# springs to see how you like it. You will be surprised to see how much adjustment you get from just the Valving Adjustment *****.
Great work and Thanks for the pictures.
Great work and Thanks for the pictures.
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
I gave the 450 springs a coat of paint (over the powdercoat) and bolted everything up, just to make sure the rodends are long enough etc.
dropped the car down on its wheels, its at 26 1/4" eyebrow height, and just a fraction over 5" at the chassis jack-up points. It can still go lower but there is 2" compression travel left on the shock so I will give it a trial run at that height and check against the rubber o ring on the shaft to see how much the shock is moving on the road.
dropped the car down on its wheels, its at 26 1/4" eyebrow height, and just a fraction over 5" at the chassis jack-up points. It can still go lower but there is 2" compression travel left on the shock so I will give it a trial run at that height and check against the rubber o ring on the shaft to see how much the shock is moving on the road.
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
It's Australia day here today, 26th January,
to celebrate we took our american cars out for a drive !
we had 21 vettes out for a cruise before a traditional barby.
the coil-overs performed well, and nothing fell off !!
to celebrate we took our american cars out for a drive !
we had 21 vettes out for a cruise before a traditional barby.
the coil-overs performed well, and nothing fell off !!
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
in south australia all cars built after 1980 must be right hand drive, so all c4/5/6/7's are right hand drive. most australian states follow this rule.
it effectively doubles the cost (and value) of converted american cars.
but for some reason there is a heap of left hand drive DeLorean's that are registered in south australia ?
it effectively doubles the cost (and value) of converted american cars.
but for some reason there is a heap of left hand drive DeLorean's that are registered in south australia ?
Melting Slicks
Joined: Jan 2008
Posts: 2,620
Likes: 81
From: Florence SC
St. Jude Donor '12
Jim
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
Generic heim joints or Corvette specific? I am putting a set of Van Steel coilovers on my 94 and changing my bushings for poly. Not a fan of the oem end link mount and haven't found any heim joints that are for the C4. Had them on my C5 though. Any info would be appreciated!
Jim
Jim
the bolt on the end of the sway bar is 7/16" so I chose that size for the rodends.
I used a 7/16 male right hand thread and a 7/16 female right hand thread.
the washers are 7/16 hardened, and the bolts are 7/16 high tensile zinc coated.
you guys in the states are lucky, you can find this stuff everywhere cheap with free shipping, or just go to the local fastener place that sells this type of stuff, and get chromemoly or stainless.
if you look at rsc337's thread he has the later model suspension arms so you can see they are slightly different, but you can just bolt the rodends straight to the arm (unlike the early arms where you need to fab a bracket to do this)
he moved his sway bar forward, or you can do what i did and grind the back of it for clearance as the rodends give you a bit more clearance as well.