How strong are rivnuts?

[colojeepguy]

I'm trying to mount a power brake booster on my firewall. Access up under the dash is very tight, can I use 3/8 rivnuts for this? Would they be strong enough?
I should add that the firewall in this area is reinforced for mounting the brakes (this is on my Commando)

 

[PeteL]

They are available in different types of metal. Consider using stainless versus aluminum, for instance.

In my limited experience, care of installation makes a big difference, as does the strength of the receiving sheetmetal. Possibly a backing plate or washers would be a good idea.

 

[Norcal69]

I'm trying to mount a power brake booster on my firewall. Access up under the dash is very tight, can I use 3/8 rivnuts for this? Would they be strong enough?
I should add that the firewall in this area is reinforced for mounting the brakes (this is on my Commando)

Steel should work just fine.

 

[47v6]

I'm trying to mount a power brake booster on my firewall. Access up under the dash is very tight, can I use 3/8 rivnuts for this? Would they be strong enough?
I should add that the firewall in this area is reinforced for mounting the brakes (this is on my Commando)

I wish I had used these for just this kind of thing. You can always double up the steel on the firewall to deal with the additional stress, such as a plate under the cowl, then insert the rivnuts through both to mount your booster. What a time saver.

 

[Jeepenstein]

I wish I had used these for just this kind of thing. You can always double up the steel on the firewall to deal with the additional stress, such as a plate under the cowl, then insert the rivnuts through both to mount your booster. What a time saver.

I didn't use the rivnuts, but I did use a 3/8" thick aluminium plate on the firewall to add some rigidity.. I have a glass body, but same concept..

 

[Jw60]

We use steel ones. Use a jam nut for peace of mind on the exposed threads past the nutsert. 5/16 and 3/8 thread both use .531" hole. Use a Min edge distance of 3/4"

 

[cj2atruck]

I have steel, aluminum and stainless in the shop, and for a project like this I would use steel. Put anti seize on the threads and add a backing plate that is held on with the rivnut as others have suggested and you should be fine.