IRS - Tires rubbing on shock springs

[elspanishgeek]

Happy Thanksgiving Eve, everyone!

I finished mounting the IRS and Wilwood brake upgrade. I did the rough alignment according to the manual for both the upper control arms and toe arms of 11 1/2'' and 17 3/8'' respectively.

UCA Dimensions
175442

Toe Arm Dimensions
175447

I then mounted the rear tire to continue to set the rough camber and toe alignment and I'm finding that the springs of from the coil-over shocks are rubbing on the tire.
175446
175448

I checked to see if perhaps I had too much negative camber but the level is coming out right smack in the middle.
175443

Here are my UCA and toe measurements for sanity check.

UCA measurement
175445

Toe arm measurement
175444

At this point, I see two options and wanted to check with the gurus: Do I flip the shocks (as it seems body up/spring down would fix the problem) or do I extend the UCA and toe distance by about 1/2''?

Thank you, and hope all your turkeys are defrosted already!

[Hoooper]

Car has to be on the ground and with all the weight on it. You cant do an alignment with it up in the air, the numbers in the book are just to get you started/in the ballpark. The springs are very close or do rub when up on stands but it will be fine on the ground.

[Sharris2]

Turn the shocks and springs over; sprung vrs. un-sprung weight. You will find a little extra space; not much

[edwardb]

What size tires? Unlikely an issue, but part of the equation. Many others have reported this concern during the build and it always worked out once on the ground, at ride height, and the alignment dialed in. You can flip the shocks if you want. The red Konis can go either direction. But for the silver Konis (what I have on two IRS builds) they have to go body down (the way you have yours) and clearance while close wasn't a problem.

[elspanishgeek]

My concern is that the springs are really pressed against the tire, and I'm worried about setting it down and damaging the tire in the process.

The tires are the Halibrand 17'' supplied by FFR.

[edwardb]

My concern is that the springs are really pressed against the tire, and I'm worried about setting it down and damaging the tire in the process.

The tires are the Halibrand 17'' supplied by FFR.

Then adjust the camber to move the top of the tire out when the chassis is lowered and the ride height set. The dimensions in the manual are just a starting place. With that much pressure guaranteed the dimension isn't close enough to matter. This will get sorted with the proper camber and toe adjustments. Whole bunch of builds with your combination of parts.

[Hoooper]

It wont damage the tire, but if youre concerned you can set it down slowly to be sure. Mine I cant move or mess with the spring when it is up in the air like that because the tire has it stuck in place, no big deal and its been up and down many times plus a few thousand miles on it. As soon as the tire hits the ground when putting the car down the tire starts moving away from the spring.

[elspanishgeek]

Thank you for the quick answers, everyone!


Then adjust the camber to move the top of the tire out when the chassis is lowered and the ride height set. The dimensions in the manual are just a starting place. With that much pressure guaranteed the dimension isn't close enough to matter. This will get sorted with the proper camber and toe adjustments. Whole bunch of builds with your combination of parts.

I pushed the UCAs out by 1/8'' and tucked in the toe arms also by 1/8'' (now 11 5/8'' and 17 1/4'' respectively) and cleared it enough. Following all the comments (and the slew of other posts and threads about this), I'll consider this good enough until it's set on the ground with the full weight of the engine and transmission.

Happy thanksgiving!

175472

[Fasteddie41458]

I have installed wheel spacers for my clearance, not using the FFR wheels.