Bolt Pitch

[169mph]

Sorry guys I’m not expert. In fact I had no idea what bolt pitch meant until a couple of weeks go. Yes, i meant 1.5 vs 2.0. I’m worried about retap differential. I could that going bad for a number of reasons. After reading a little more about bolt pitch I feel like the 1.5 would be preferable but the the 12.9 14mm 2.00 bolt would work fine. I think I’m talking myself into going with the 12.9. 14mm 2.00 bolt. I haven’t driven the car in over a month. Is this a mistake ands it’s going to bite me done the road? I appreciate the feed back. Thanks, Mike

[cycleguy55]

Originally Posted by 169mph

Sorry guys I’m not expert. In fact I had no idea what bolt pitch meant until a couple of weeks go. Yes, i meant 1.5 vs 2.0. I’m worried about retap differential. I could that going bad for a number of reasons. After reading a little more about bolt pitch I feel like the 1.5 would be preferable but the the 12.9 14mm 2.00 bolt would work fine. I think I’m talking myself into going with the 12.9. 14mm 2.00 bolt. I haven’t driven the car in over a month. Is this a mistake ands it’s going to bite me done the road? I appreciate the feed back. Thanks, Mike

If the differential is tapped M14 x 2.00, the only way to tap it to 1.50 mm pitch is to go larger (e.g. M16 x 1.50). As noted by Dominik, the 2.00 mm pitch has a smaller thread root diameter than the 1.50 mm, so you'd end up with partial threads that wouldn't hold. You'd have to go larger in order to have enough metal for the threads to hold.

You should probably stick with the M14 x 2.0 but, as eschaider wrote, find a bolt with a longer shank. I had to do that last year with a smaller bolt, and ended up buying a longer bolt to get the proper shank length, then cutting off the excess threads to get the length I needed. Not the easy route, but the proper way to do it.

[spdbrake]

Sorry I missed the fact you had already been upsized to a 14x2.00 bolt.

You can stick with the 14x1.5 in the Condor kit by installing a Helicoil.

14x1.50 kit here:https://www.rivetsonline.com/thread-...14-15/rc-37148
I'd stick with the Recoil brand as the Helicoil kit same size is $263.00 VS $102.00

Instructions on page 6: https://www.recoil.in/download/recoilTech.pdf

[cycleguy55]

Originally Posted by spdbrake

Sorry I missed the fact you had already been upsized to a 14x2.00 bolt.

You can stick with the 14x1.5 in the Condor kit by installing a Helicoil.

14x1.50 kit here:https://www.rivetsonline.com/thread-...14-15/rc-37148
I'd stick with the Recoil brand as the Helicoil kit same size is $263.00 VS $102.00

Instructions on page 6: https://www.recoil.in/download/recoilTech.pdf

Yes, that's an excellent alternative. Helicoil or similar inserts are often stronger than equivalent threading - particularly in aluminum. Galling due to dissimilar metals is also eliminated. I've used Recoil inserts, though none that large.

I will note the M14x1.5 bolt supplied in the kit is almost fully-threaded, however, so perhaps not the best fastener for the application.

[spdbrake]

Good point Brian. Regardless the weak point on a all-thread and partial thread still will be the threads as they are exposed at the diff bolt hole entry point.

Another alternative is: Since the bolt hole on the Diff is a through and through a nut and washer can be placed on the back side.

Chase the hole to allow a 14mm bolt to be a slip fit.

Sold here in 14x1.5 and 14X2.0 (the 220mm is 8.6" long for example, plenty long enough)
https://belmetric.com/m14x1-5-fine-d...H14X1.5X220YLW

Have to measure what you need once the diff is remounted.