Clearance between tire and spring seat

[mbuskuhl]

I put on some new wheels and have exactly 1/4" clearance between the tire and front spring seat. I don't think this is enough for comfort or flex/suspension travel, what is the minimum distance you'd like to see?

The car is a 2nd Gen RX7, 225/50 tires, 15 x 7 + 35 wheels, currently 3/8" spacer which gives me the 1/4" clearance. I was going to go to a 1/2" spacer or stack a 3/8" and 1/4" to get 5/8", either I way I need to buy more spacers. How much clearance do I need for comfort before I buy some new spacers?

[Knestis]

I put a square of tire crayon on the inside sidewall and if it rubs off, it's too close. If it doesn't it's OK. :)

K

[RSTPerformance]

Good idea K...


I have been closer than that before and not had any issues.


Raymond

[seckerich]

I put on some new wheels and have exactly 1/4" clearance between the tire and front spring seat. I don't think this is enough for comfort or flex/suspension travel, what is the minimum distance you'd like to see?

The car is a 2nd Gen RX7, 225/50 tires, 15 x 7 + 35 wheels, currently 3/8" spacer which gives me the 1/4" clearance. I was going to go to a 1/2" spacer or stack a 3/8" and 1/4" to get 5/8", either I way I need to buy more spacers. How much clearance do I need for comfort before I buy some new spacers?
[/b]
Run the 1/2 inch spacer (never stack if possible) and you get about 3/8 clearance with that combination. That tire will move a ton under cornering. You are running 2.5" springs? Is the perch too big or just to the edge of the spring?

[mbuskuhl]

I did the tire crayon this past weekend with some 15 x 6.5 + 40 and a stacked 3/8" and 1/4" spacers to get me by - no rubbing. Now that my new wheels are in and on the car I'm trying to get the right spacers and the good high quality ones. I will definately do tire crayon again next track time to verify.

I'm going to pickup 1/2" spacers now, that should give me at least 3/8"clearance. I am running a 2.5" spring and got all of my suspension from Flatout motorsports. The car recently had a setup done by the MX-5 cup points leader Saini, it handles good so I don't think anything is screwy with the suspension. I was able to "roll" a regular pencil (not move freely) between the tire and spring seat, the pencil measured .28" with a micrometer.

I just thought of this, maybe my wheels are not +35? I ordered them from Team Dynamics and that's what they had in stock. It doesn't say the offset though on the box or the wheel - they are the Pro Race 1. I did order and they did tell me they are +35... not sure how to actually verify.

[ITC Racer]

Checking the clearance with the crayon should show what is happening but with most roadracing tires, the sidewalls are so stiff that you should not see too much deflection.

I just started using some 225/45-13s on my CRX and only have 3/8" clearance in the rear but have had no issues.

Make sure you have enough lug length for the wheel spacers also!!

[spnkzss]

I just thought of this, maybe my wheels are not +35? I ordered them from Team Dynamics and that's what they had in stock. It doesn't say the offset though on the box or the wheel - they are the Pro Race 1. I did order and they did tell me they are +35... not sure how to actually verify.
[/b]

You'll ahve to do a quick search to find what +35 equals I don't know off the top of my head. My +38 is 4 inches of back space. Take a flat edge across the back of the WHEEL. Then measure from the bottom of the straight edge to the back fo the wheel that sits against the hub.

[seckerich]

With a straight edge on the back lip of the wheel it should be 5" backspace on the team dynamic.