Is anybody thinking of running coilovers in the rear?

AleX1/9

AleX1/9

Well-Known Member
I like the idea of continuity in a build when it comes to the components used, and I've been thinking of using some QA1 coilover sleeves and springs on the front struts. I also like the idea of being able to tune the suspension with different spring rates, swap-able front to rear.

I'll be cutting the front struts apart to install the Koni inserts, what's stopping me from cutting off the factory spring perch, and welding on a coilover sleeve perch? The vintage Fiat guys have been doing this for decades (until recently 2 suppliers brought coilover systems for sale).



My question is, what spring rates would you guys use? From my research, the factory spring is a progressive rate with 220#/in coils mixed with softer 90#/in coils. Also, what spring rate/size is on the supplied front springs with the Goblin kit? What top hat arrangement would you use?

I was planning on waiting until I got the Goblin so I could get a good feel of how the strut top is mounted to the Goblin, what the supplied spring rates and sizes are, what colors the springs/coilover sleeves are, etc but I figured I might get a jump start by finding out here
 
Last edited:
rallyracer

rallyracer

Well-Known Member
Funny you brought this up. I tried getting some information on what setup these cars are running a number of days back. I have yet to hear anything back from the Goblin crew :/

I was looking into getting a double adjustable pro touring setup from a local company.
 
Last edited:
T

TomsGarage

Active Member
I was thinking of doing something like this as well, but buying a pair of front coilovers already built for the cobalt. The QA guys said that we would be able to do something like that.

This is what I received a while back:
"
Thomas,

Thank you for your interest in QA1 products. To recommend a coil over for your vehicle we would need to know the measurement from mounting point to mounting point of the shock with the vehicle at ride height. I would also need to know the rear weight of the vehicle to know what spring rate to select.

Thanks!


Tim Anderson

Circle Track Technician"
 
AleX1/9

AleX1/9

Well-Known Member
Researching the aftermarket coilover set ups they all use 6k-7.5k springs which is 335-420 lb/in. Considering the goblin will be lighter than a cobalt, I'm going to start with the 300lb/in eibach coilover springs I happened to already have. Maybe order some 250's or 225's with the sleeves.

Here's the struts drained of oil and ready for the saw
 
AleX1/9

AleX1/9

Well-Known Member
Chucking the OE strut shaft in the vice allows you to keep your sawzall in one spot and rotate the housing to sever the top.



Reading the directions, koni wants the strut tube to extend 6mm past the dimples. Rather than use the measurements given, I cut them long and sloppy, and measured from the bottom up for the final cut



the dimples are 11.5 " from the bottom mounting surface


This one needs another 1/2" or so lopped off


Strut tube is 2" OD

 
Last edited:
AleX1/9

AleX1/9

Well-Known Member
rallyracer said:
Did you successfully get them together?
Click to expand...
I'm still waiting on the QA1 coilover sleeves to arrive from summit racing. I want to verify the sleeves will work before cutting off the factory spring perch.

Also the koni inserts look like they could be a one shot deal. The dimples are so much larger than the ID of the tube, they likely crush into place during install. Removal could be difficult, and re-install less than ideal.
 
AleX1/9

AleX1/9

Well-Known Member
Got shipment #2 from QA1 today:



These are part # COK104 (need two). Going to work well, time to hack off the factory spring perches!
 
AleX1/9

AleX1/9

Well-Known Member
Johvans said:
Please post pictures once they are completed! Looks great! What is your planned spring rate?
Click to expand...
I'm going to start with 300lb/in and work my way down from there. I anticipate ending up somewhere close to the 200lb-ish factory spring rate.

Note for others considering this mod, the top lip of the koni strut does not fit through the coilover sleeves that I have, and has to be filed down slightly to fit through. I did mine by hand as to not create too much heat. Will post pics when finished. might be a little while out, as I'm occupied with stripping my donor/getting the frame ready for powdercoat at the moment.
 
Adam

Adam

Administrator
Staff member
What you are doing is very cool. Right now on P2 I've got a standard sized coil spring resting on the stock spring perch. It functions well enough for testing but doesn't look nearly as good as your coilover sleeve and height adjustment hardware.
 
JSATX

JSATX

Goblin Guru
Adam said:
What you are doing is very cool. Right now on P2 I've got a standard sized coil spring resting on the stock spring perch. It functions well enough for testing but doesn't look nearly as good as your coilover sleeve and height adjustment hardware.
Click to expand...
Adam I want to install some KSport coilovers in the back, the problem is they use the three bolts around the strut to mount up. Can the little plates you make for the goblin be unbolted and a different plate bolted in, one that is made more like the stock mount? I like the idea of the adjustable camber plates.
 

Attachments

Johvans

Johvans

Well-Known Member
JSATX said:
Adam I want to install some KSport coilovers in the back, the problem is they use the three bolts around the strut to mount up. Can the little plates you make for the goblin be unbolted and a different plate bolted in, one that is made more like the stock mount? I like the idea of the adjustable camber plates.
Click to expand...
You SHOULD be able to run the KSport coil overs assuming they are separate from the toe adjustment plate. It SHOULD mount like the standard shock after the plate is removed. Might be worth finding some pictures of the KSport unit out of the car.
 
AleX1/9

AleX1/9

Well-Known Member
Bringing this thread back from the dead now that the coilovers are done!

Since last posting, I shortened the strut tubes to the appropriate length, drilled the bolt holes in the bottom, and welded flat coilover sleeve perches onto the strut tubes.

After some paint



The dimples on the top and this bolt on the bottom hold the Koni insert into the modified OEM shock tube



I fiddled with the sleeve to shock body fitment for a while. Ended up using a combination of rubber O-rings and the rubber sleeve supplied with the shocks.

The Konis also came with this dust containment ring, and it fits sooooo nicely in the tapered end of the QA1 sleeves



Ready for Install





I'm still waiting on a shipment from DF with the rear upper mount pieces, so no pics on the car yet.
 
JSATX

JSATX

Goblin Guru
Those look awesome! What do you think the cost came out to doing it that way as opposed to just getting the coil overs from DF?
 
AleX1/9

AleX1/9

Well-Known Member
Cost breakdown:

Koni 8641-1500 struts $175ea x2
QA1 COK104 sleeve kit $130 ea x2
Eibach or QA1 8x2.5x300lb springs $70ea x2
Coilover perch rings from technotoytuning $20

Add in the paint, O-rings, cutoff wheels etc I’m in to these things darn near $800

I started these before the coil overs were available from DF, would have been much easier and almost as good to go that way

edit: I also bought two sets of camber bolts. SPC #81250 $20/pair x2
 
Last edited:
Andy

Andy

Well-Known Member
Awesome build i kept the old struts to tinker with. I like the above build. I am also interested in the overall cost.
 
AleX1/9

AleX1/9

Well-Known Member
The upper mount pieces came in the mail today, and I was able to mock them onto the car. I'm surprised everyone paints these things, they look like freshly machined awesomeness.



I was hoping I could use the QA1 upper hat's thrust bearing setup because it makes the spring really easy to spin and the flange on the top of the conical QA1 cap pressed right into the machined DF upper mounts - like perfect fit.... But, the whole setup is too thick and doesn't leave much more than 3 threads on the top nut. I'll have to hit up the hardware store for a washer that drops into the tophat and will go flat against the upper mounts. I'm also going to need some allthread bolts to save me from drilling out this thick powdercoat



 
Last edited:
You must log in or register to reply here.
Top