Centerline Telstar 15x8 and 15x4 Installation
*Disclaimer -- This write-up involves removing metal from your brake calipers, and if you take too much off you WILL compromise the structural integrity of the caliper, which could lead to catastrophic failure, loss of braking ability, and possible destruction of the car as well as personal injury or loss of life. Follow the instructions contained herein AT YOUR OWN RISK. I assume no responsibility for your own actions based on this guide. This is meant as an informative guide to getting these wheels to work on a particular setup. That said.....on with the info:
The Centerline Telstar wheel is a budget friendly and more installation friendly wheel for the 4th Gen F-Body vehicles than other wheels of the like (Weld and Bogart come to mind). The most obvious advantages of the Telstar when compared to the others is the fact that these wheels use a standard acorn lug nut, and not the shank style (SST) lugnuts which require longer wheel studs to pass NHRA tech. As GM High Tech Performance has proven, these are a direct bolt-on for the 93-97 LT1 F-Body carline. No spacers or caliper clearancing required. But, what about LT1 cars with LS1 front brakes, or LS1 cars??? That's where this write-up comes in.
Centerline Telstar 15x8, 5.5 Inch Backspacing, part number CLL-135807574 from Summit Racing
Centerline Telstar 15x4, 1 5/8 Inch Backspacing, part number CLL-135401547 from Summit Racing
The car in question here is my 93 Trans Am, which was bought already having LS1 front brakes installed. These wheels were initially purchased for my other (former) 93 which had LT1 brakes up front. Installation issues weren't even a thought until test fitting these and it became obvious that there were clearance issues with the LS1 front brakes. The larger and wider front calipers were contacting the the wheel.
Options?? There was no clear answer as to what to do on any of the boards, so I tried a couple of things. It was either grind the caliper down some, or use a 5/16" spacer and chance using stock wheel studs or run longer wheel studs. The latter of the two poses another issue, that being that longer wheel studs suddenly give you issues when reinstalling your regular street wheels, as you'll no longer be able to run a closed end lugnut, you'll have to run an open ended nut and it will look like butt. So.........
Above you can see why I went with the grinding option. The first pic shows the wheel installed without the spacer (these were taken after caliper clearancing for accurate results), the second pic shows with the spacer and the stock wheel stud. I would NEVER trust an installation like this without using a longer wheel stud. There are those that do, and I must ask how you lug around those brass balls everyday.
In the first picture, you an see that I used masking tape along the outer corner edge of the caliper. In the subsequent pic, you'll notice that I mocked up the wheel on to the car. Just hand tighten a couple of lug nuts and rotate the wheel around a couple of turns. This last picture shows where the initial clearance issues are by the scraping in the masking tape.
In this next set of pictures above, you'll see that I used a ball of clay on the hub as a measurement tool. I mock-installed the wheel again, and when removed, measured the approximate thickness that would need to be taken down. The third pic shows the relative thickness of the caliper where the grinding is going to be necessary. So let's get started!!!!
First Pic: The angle grinder is your friend. I had a couple of metal grinding wheels, and a 120 grit flap disc for finishing. I bought everything needed for less than $50, and it's always nice having more tools. Anyway, on to the work.
The series of pictures above shows the various stages of grinding that were completed. This is a LOUD, and while not labor intensive task, it can be tedious. My biggest thing I can say here is grind a little bit, put a piece of masking tape on, and check your clearance. Work in little bits, and you won't run into a situation of having taken too much off of your caliper. *Note* Clearancing is going to depend on how much brake rotor and pad thickness you have left. The thinner those are, the less clearancing necessary. I had to do about as much as possible as my brakes are less than 10K miles on brand new rotors and pads.
After getting the majority of clearancing done, I noticed that I seemed to have a couple of trouble spots that weren't on the caliper. Upon further inspection of the inside of the wheel itself, I found that there were two very large weld start points that were sticking up much farther than the rest of the welds. Using the 120 grit flap wheel on the angle grinder, these were quickly taken down and it was back to working on the caliper
Another repeating sequence of grinding, masking, and checking, and suddenly, we have free rotation without anything touching. Looks like we've accomplished what was intended. All I had to do to finish up was use the 120 grit flap wheel to smooth out the ridges and edges and make it look all pretty.
For reference purposes, here is the passenger side caliper that is untouched, and the drivers side caliper which is now fully clearanced so you have a reference point as to how much was taken off overall.
The rear calipers required no modifications at all, but these were on the LT1 brakes. The LS1 rear brakes are larger, and will require clearancing, but how much I don't know as I've not had any experience with those yet. As for offset.....you can be the judge of that as to how well the front and rear wheels fit. The first two are the rear obviously and the third is the front drivers side.
Finished up, everything fits like a champ, and I now have a proper wheel and tire setup to run at the track. The front wheels tuck beautifully into the wheel wells too!! I hope this was able to answer some of the questions concerning fitment of the Centerline Telstar wheels to an F-Body with at least LS1 front brakes and LT1 rear brakes.