This month, we’re going to look at a tool that is cheap enough to have on hand before you need it and can save you from big headaches and costly repairs. We are, of course, talking about a thread-chasing tap and die set, specifically the kit from Summit Racing (P/N: 900199).
Designed to repair damaged threads (as opposed to cutting new ones), the Summit Racing Complete Thread Cleaning Kit comes with 26 taps and dies designed to clean, restore, and repair common SAE coarse and fine threads. Unlike traditional taps and dies, thread chasing dies do not cut or remove material, but rather reform and smooth out existing thread forms.

The Summit Racing kit comes with 26 different rethreading taps and dies. Look below for the specific sizes included, but there are six coarse-thread and six fine-thread taps, and seven coarse-thread and seven fine-thread dies included in the kit.
We’ve discussed before that dirty or damaged threads can lead to a wrecked block. By simply running thread-chasing taps through the threaded holes in your block, you are sure to not run into any issues when threading in the myriad of fasteners required by your engine. In fact, even if you don’t think there is any damage to the threads, the thread chaser can clean out unseen debris that can lead to issues.
On the left, you can see the difference between a thread-chasing tap (top) and a thread-cutting tap (bottom). On the right, you can see that the thread-chasing taps have a hex head built in, eliminating the need for a tap wrench, and allowing the use of standard sockets or open-ended wrenches (although, you shouldn't need that much force on the thread chasing tap).
Taps and Dies
Thread-chasing taps and dies have visually obvious design differences. While there are several types of cutting taps, the thread-chasing tap varies in that the threads start immediately, and don’t have the large channels to clear the cutting debris generated by a typical tap. Also, the threads aren’t sharp, as they are designed specifically not to cut.
Sizes Included in the Summit Racing Kit
COARSE THREAD | FINE THREAD | ||
Taps | Dies | Taps | Dies |
1/4″-20 | 1/4″-20 | 1/4″-28 | 1/4″-28 |
5/16″-18 | 5/16″-18 | 5/16″-24 | 5/16″-24 |
3/8″-16 | 3/8″-16 | 3/8″-24 | 3/8″-24 |
7/16″-14 | 7/16″-14 | 7/16″-20 | 7/16″-20 |
1/2″-13 | 1/2″-13 | 1/2″-20 | 1/2″-20 |
9/16″-12 | 9/16″-12 | 9/16″-18 | 9/16″-18 |
5/8″-11 | 5/8″-18 |
The same differences apply to the dies, which can be extremely handy for cleaning up rusty or damaged studs, or even bolts that are hard to find replacements for. Another cool feature of most thread-chasing taps, the Summit Racing kit included, is that you don’t need a tap wrench or tap sockets for the taps. They have built-in hex ends that will work with traditional open-end wrenches and sockets — although you probably won’t need too much mechanical advantage.
Whether you have a specific issue you need to fix, or just want to ensure your block (or any other component with threads) is perfect before assembly, a set of thread-chasing taps are the right tool for the job. And for the price, a set should be in your toolbox, just in case.

For our factory small-block Ford block, we didn’t have any issues ahead of time, but did have some gunk come out of the holes when we ran the 7/16″-14 thread-chasing tap through the head-bolt holes.