Race Car Scales and GM 10 Bolt - Q&A Track Tech

Weighing Your Options: Scales and rearends

I'm going to be getting into street stock racing and I have some questions.

Do you think a set of scales would be a good investment for someone starting out, and if so could you recommend a set at a reasonable price?

Also, do you think a GM 10-bolt rearend would stand up on a paved quarter-mile high-bank track? Also, do you have any advice about setting them up for racing? I'm going to be on a tight budget and I thought a 10-bolt would be cheaper.
Thank you.
Joe Gramlich
Via e-mail

If you are planning to go racing for any length of time, my recommendation is to purchase a set of scales sooner rather than later. This is one of the best investments you can make in a racing program, because with them you can begin to understand your setup and make the adjustments necessary to be competitive.

Here is what I would advise about the purchase of a set of scales. There are a lot of manufacturers of scales around, and it's important that what you purchase is accurate. It's not necessary to buy a top-of-the-line scale set for a budget program, however, it is important to have accuracy. Make sure the wheel pads on a less costly set are the same as those on the more expensive set being offered by any given company. If they are interchangeable, this should give you the assurance of accuracy and performance in the less expensive set. An economic set of scales will probably start somewhere around $1,100 retail.

Regarding the stamina of a GM 10-bolt on a quarter-mile high-banked track. I think the 10-bolt has limitations that may make you consider using a 9-inch Ford rearend instead. The 10-bolt has a limited ratio of up to around 5.38:1 to 5.60:1. The kind of track you are running on needs a gear ratio around 6.00:1. To get the necessary performance from a 10-bolt, you will have to do a ring-and-pinion match and run in Second or Third gear (depending on the transmission you run) to get a final drive that puts you in the 6.00:1 range. Obviously, this kind of thing puts extra strain on your transmission. The Ford 9-inch is more stout and offers ratios in the 6:00:1 to 7.00:1 ranges, which permit the tranny to operate in a less stressful environment.

Another thing to consider between the two types is the cost of maintenance. I have seen both axle bearing and axle breakage difficulties with the 10-bolt system in this environment. Also, mini spools are more costly for the GM setup. It's true that the cost of the 9-inch is a little higher but, in my view, the cost of maintenance of the 10-bolt makes the 9-inch a better choice for your program. The 10-bolt will continue to be used by many in a program such as yours. However, I believe that when you weigh the advantages of the 9-inch, it's a more cost-effective piece. As a postscript, if you go with the 10-bolt, you will need to run the 8.5-inch GM 10-bolt.
-Ken Roper
Fast Lane,
Woodstock, GA