Speaking of break-in, what is the proper break-in process?

These pieces really don't require any break in. Just bolt it up, fill it with high-quality gear oil and hit the track. Bottom line, that's not going to hurt it. And it has to be that way because if the big 410 Sprint touring guys wreck and tear up a rearend during the middle of the year, they are going to put a new one in and go racing. There's no time to spend a bunch of effort breaking in a new rearend. If you want to, you can jack the rearend of the car up and run the car at 2,000 rpm for 20 minutes as a break in, but in terms of the quality of performance and longevity, what we've seen is our rearends, at least, don't require any dedicated break-in process.

What range of gears should I bring to the track?

Like I said before, I really don't think you need to buy every gear in the catalog if you are smart about your gear choices. I have a hard time thinking anybody can tell a difference in five points of gear change. I've been racing a long time myself, and I know I can't tell from the driver seat. As an example, one inch of tire size change equals about five points of gear change. Now, if you are making a tire-size change and a gear change together in order to get 15 points of change, I can understand that. But if you are going to open up the quick-change cover to make five points of gear change, I think that's a bit of a waste of time and you probably will be better off working on your suspension.

In general, a 12- to 15-point jump is where a driver is going to be able to feel something on the racetrack. So I recommend, if you know generally how you want to be geared, you can carry three gears with you to the track for a 30-point sweep. But again, a lot of it has to do with your setup. If your car is right, you really don't have to change your gear too often. Honestly, a lot of times I'll see guys swapping gears when the real problem is the chassis setup or the wiring between the driver's head and his foot.

But to get back to it, having the right selection of gears in a 10- to 12-point sweep is a lot more important than buying and carrying around a bunch of gears that are too close together in ratio.

How useful are lightened and polished gears?

They do definitely work in terms of allowing more of the power your engine makes get to the rear wheels. Anything you can do to cut rotating weight or friction without making the gears too fragile is helpful. Our premium quick-change gears are both lightened and polished, and the premiere sets we offer have been lightened and polished, but they have also been cut to a narrower width.

For example, your basic standard quick-change gears weigh 6.25 pounds on average. But when you go to our lightened premium gear you are talking 4.5 pounds on average. That's a big savings right there; you're talking about 1.75 pounds of rotating weight. With our top-of-the-line gears we are able to get them down to 3.75 pounds by reducing the gear width. At the teeth, the gear is only 1 inch wide, but the spline area is actually still a standard width so the racer doesn't have to run a spacer or have to worry about forgetting the spacer and screwing up their equipment. And we didn't make a gear that's fragile, either. Those premium 1-inch-wide gears can handle full-power race cars no problem. They are actually rated for up to 1,000 horsepower.

What about lightening the ring-and-pinion?

That can also be very helpful. But you have to be careful, because lightening any gear really requires using high-grade steel. And a good lightening program can be really helpful for the guys that are racing on limited horsepower because it will help you get power to the ground more efficiently.

We have a lightening package that we do on our crate stuff, or really anything that will be under 500 horsepower. We can take around 2.5 pounds off the ring gear and it can still handle that power level reliably. Some of our competition in this market has tried to push a smaller ring-and-pinion, and we can get down to that same weight with a standard size gear. The advantage of that is if you move up to a higher horsepower class, all you need to purchase is a new ring-and-pinion. Everything else still works. But if you use the rearend featuring the smaller ring gear you will have to purchase an all new rearend. So, intelligently lightening your ring gears has a lot of advantages because you can match the lightening program to your application.

Do super lightweight gears like that require any extra precautions?

Yes. The more you lighten your gears, the more inspection you will need to do. Scalloping a gear promotes more flex and more movement. That means the gears themselves need to be watched for signs of wear, but you also need to check your ring gear bolts because flex can also cause bolts to work loose. So, with lightened ring gears you definitely need to inspect your ring gear bolts every handful of races.

SOURCE
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