Good rear coilovers to have 245/60R16 tires? (Page 1/1)
Squall86GT OCT 16, 09:32 AM
Hey guys,
The tires on the back of this thing just look too small. There’s some aftermarket wheels that are 16“ x 7“ wide I believe. Anyway I’ve got plenty of room in the wheel well and it would help out those RPMs a little bit- what is a good solid coil over kit for the rear that would give me plenty of space to have tires are a lot wider and a little bit taller? Thanks!
Spadesluck OCT 16, 11:30 AM
You have really two options:

1. Make your own

2. Purchase from Fieroguru
olejoedad OCT 16, 11:46 AM
Depending on wheel offset, you may not need coilovers.

I run 245/45/17's with original struts.
pmbrunelle OCT 16, 12:14 PM

quote
Originally posted by olejoedad:

Depending on wheel offset, you may not need coilovers.

I run 245/45/17's with original struts.



Offset of your wheels that work without coilovers?

And original GM struts? Or aftermarket such as KYB, Monroe, Gabriel?
olejoedad OCT 16, 05:22 PM
17x7x40

88 Formula
Probably has KYB's on it.
fieroguru OCT 16, 08:14 PM
The 88s have more room to the spring perch as the strut mounts a little higher and more of an angle to the knuckle.
Squall86GT OCT 16, 11:25 PM
Got an 86. Would this work? https://www.ebay.com/itm/381755089522

How does one know how much bigger of a tire or a particular coil over will let you have?
fieroguru OCT 17, 10:25 AM
The interference issue is with the lower spring perch and the larger diameter spring (4.5" OD) that sits on top of it.
To maximize the clearance, most people remove the spring perch (the linked coilovers do not do this) and switch to a 2.5" ID (3.5" OD spring).
For extreme fitments (9.5"+ wide) some keep the weld bead for the stock spring perch and mount the adjuster sleeve on top.
Squall86GT OCT 17, 10:18 PM
So you can simply remove the perch and change the springs and that allows you to have a taller and wider tire if you want to? Roughly speaking how much taller and wider than stock? I don’t wanna put monster truck tires on - just wanna understand what that will look like. Any negatives? Thanks a lot
fieroguru OCT 18, 09:06 AM
Here is a picture of a stock spring setup with a stock 15" wheel:



This is the interference you want to avoid with coilovers:


How large of a diameter tire you can run, really depends on how low you want the chassis to sit. Too large and too low the tire will hit the upper wheel well liner and upper frame rail. Stock tire diameter is about 24.6" running 25" or 26" tire with a moderate stance normally isn't an issue with frame rail clearance (but depending on width and offset you will need to make sure the tire will clear the springs on the struts).

There are several ways to build coilovers. One of the options is how to mount the sleeves.
On the weld bead of the stock spring perch. When you go this route, the need to be very careful with the spring length (10 or 8) as well as make sure there is enough compression range in the spring to avoid coil bind. If you get springs that are too long, you will be limited on how low you can lower the car. The spring shown in the picture is 10" 275 lb/in and WILL coilbind before bottoming out the strut. It also runs out of adjustment at the bottom with the car only lowered about 1".


Removing the weld bead and placing the adjuster sleeve on the knuckle bracket. This setup almost always runs a 12" spring and doesn't have any issue with coil bind and gives you largest range of adjustability.


The struts in these pictures are Konis and they have been discontinued. KYB is the most common strut used now and it has a black strut body.

[This message has been edited by fieroguru (edited 10-18-2020).]