I want to get a thread chasing set to clean up the threads on my 350 block. So I went to Summit and Jegs online and found what I want. However, summit offers one for coarse threaded holes and jegs offers two for coarse and fine. So which set(s) do I really need?? Coarse by itself or both? Does anyone know which holes on the block are coarse and which are fine? Sorry for the lame question but I don't want to ruin threads with the wrong tap.

The summit part # is SUM-900200

Th link to jegs: Jeg's kit

Thanks!!!

 

Save the money on a high dollar set of thread chasers.

Pick up a set of import tap and die set from Harbor Frieght, etc...should be about 10-15bucks for everything you'll ever use...I don't recommend tapping and threading with them (too easy to break) but they work great as chasers.

 

Or you could just get the individual taps, it depends upon the job you intend to do though, I guess.
For engines I don't end up using anything but 7/16 coarse for the headbolt holes and 3/8 coarse for the intake exh and waterpump holes.

 

These sets are not expensive, we're talking 10-15 bucks. All I want to be able to do is clean the threads by running something through them. They do not need to be repaired or anything, just clean the junk out.

Streetiron - sounds like you use the coarse threaded for almost everything. Is that a tap or a chaser?

what does everyone else use? Just regular taps?

thanks.

 

If you're talking about cleaning threads in the block, coarse threads are all there is.
I just use a tap.
For myself it's never been nessecary to clean threads anywhere except the intake, exhaust, headbolts and waterpump.
If you have some other uses in mind then maybe a set is a good idea, but for block and heads 2 sizes are all you'll need.

 

i use gun brush in cordless drill or wire brush on bench grinder