Locking hardware (nuts and bolts)

In reply to oldtin:

I have seen where the locking hardware needs to be lockwire wouldn't be an easy solution.

You could always weld the turbine to the manifold. That's super budget friendly and it'll never leak.

As a simpler alternative to lockwire, drill the bolt, and use a castellated nut.
Run a short piece of lockwire through and wrap the ends together, or use a cotter pin if you must be fancy.
No castellated nut?
A hacksaw, or composition blade in a Dremel can make the slots into the top of a plain nut.

Make your own locking washers with folding locktabs out of fender washers, or even steel soup can lids.
An extended tab or lobe bears against some nearby feature to prevent rotation (as in the Grade 8 solution Dwarf suggested).
Use snips or Dremel to shape and remove excess material.
The locktabs then get pryed up and formed tightly to the head bolt or nut with pliers after torquing.

Most COTS anti-vibration fixes are oriented towards high volume production.
But Grassroots/DIY fixes don't care if it takes a little extra time and effort.

http://www.mcmaster.com/#hex-locknuts/=jjt8n7

All metal locking nuts is what you need.

Is this a Miata?

While nut securing mechanisms are great (safety wire, stover nuts, stage 8, etc), when run hard at the track a turbo Miata will stretch the studs due to differences in heat expansion rates in the cast iron manifold and stainless steel studs. You end up with a locknut firmly still attached to the end of the stretched stud, and a loose turbo.

The solution appears to be ($$$, not challenge-budget friendly) inconel studs, as sold by FM and TrackSpeed.

A VERY long thread on the topic here

For less heat-intensive use like autox/drag strip I'd expect that stainless studs & locknuts should be fine.

A budget friendly option is to stake the nuts in place once torqued down if accessible.

I would use stainless or grade 8 fasteners and then a prick punch or nail set to deform the thread at the nut/bolt interface in a couple places.

It isn't good for frequent assembly/disassembly (unless threads are cleaned up before reassembly), but can be removed with hand tools.

Xceler8x wrote: The joint between the exhaust manifold and the turbo on a Miata can get upwards of thousands of degrees during a track day. For that reason I'm familiar with this. I had to end up using Stage 8 locking nuts with iconel studs. All from Flyin Miata. These studs. Deez nutz. Worked great. My turbo didn't stretch the studs during track days after installing these. Then my car was run over by a bucket truck.

While this is yet something else that annoys the hell out of me about my Miata, this thread is about my MX6, and studs aren't an option, unfortunately. I WISH they were, but alas....

I appreciate everyone's input so far! I think i have what i need at this point. I love this forum.

for the turbo, do what OEM's do and use lockplates. Even Nissans have them. Just find one for whatever turbo you're using. I've had them made for a T3 (cheaper than buying them) and bought them for a T25 on ebay.

Dr. Hess wrote: for the turbo, do what OEM's do and use lockplates. Even Nissans have them. Just find one for whatever turbo you're using. I've had them made for a T3 (cheaper than buying them) and bought them for a T25 on ebay.

Hrm that's an interesting idea... i'd have to make one, though.

I assume i'd need 4 total since i'm using bolts and not studs.

You just need 2. One plate fits over 2 holes, then after you tighten everything down, you bend the tabs up. Here's one for a sr20det (T25): http://www.ebay.com/itm/230844800449

Dr. Hess wrote: You just need 2. One plate fits over 2 holes, then after you tighten everything down, you bend the tabs up. Here's one for a sr20det (T25): http://www.ebay.com/itm/230844800449

Maybe i'm not thinking this through correctly...

I have 4 bolts, 4 nuts. No studs.

If i use two of these, then i can only cover say... 4 nuts. Leaving the bolts still able to rotate.

Correct?

Use em under the bolts also?

I've made an emergency cheapo version of the lock plates with a piece of mild steel. Drill 2 holes for the bolts, torque 'em down and bend a corner up.

'Jetnuts' are the shizznit, though. That's the 'distorted MIL grade nut' shown on the McMaster page.

Curmudgeon wrote: I've made an emergency cheapo version of the lock plates with a piece of mild steel. Drill 2 holes for the bolts, torque 'em down and bend a corner up. 'Jetnuts' are the shizznit, though. That's the 'distorted MIL grade nut' shown on the McMaster page.

Isn't that (home made lock plates) what I suggested?

I think putting a pair under the bolt heads as well would probably work, if that's how you're doing it. The two for five bucks plus shipping on ebay is a bargain. Lotus (T3) lock plates are like ten bucks each, and one manifold R&R takes like 6 of them.

I ordered 2 sets on ebay from one of the Nissan dealers, one set for me (Dr.Linda's Europa with a 1NZFE plus a T25) and one for my friend (SR20DET 240SX, T25). They sent me 2 plates. Emails back and forth until the seller realized he was not thinking and that the auction clearly states "one pair" per set and I ordered "2 sets" and they sent me the other pair. Each plate came in a separate Nissan parts bag. So, look closely at how the auctions are worded and make sure they realize you are buying 2 sets of 2 each.

http://www.nord-lock.com/products/multifunctional-wedge-locking/

These locking washers are great in industrial applications. Made from stainless (or available in stainless). The only downside is that you can only use them once. Repeated tighten-loosen operations will make them less effective.