ARP Stainless Exhaust Bolts

[stevesprint]

Has anyone used ARP Stainless Exhaust Bolts into the heads long term and would you recommend them?

I bought some a while ago but I’m now nervous to use them as I had to shear my stainless nut and bolts off the exhaust flanges.

[bobfather]

I'm using some currently. The only real benefit is the smaller hex head which makes spannering easier. The bolt flanges are too small limiting contact area, you can't use them with nordlocks because the bolt coating is too hard for nordlocks to cut into. They come loose irritatingly quickly

[phazed]

bobfather said:

I'm using some currently. The only real benefit is the smaller hex head which makes spannering easier. The bolt flanges are too small limiting contact area, you can't use them with nordlocks because the bolt coating is too hard for nordlocks to cut into. They come loose irritatingly quickly

Been there etc.

I've come to the conclusion that the original 9/16ths head steel bolts with new spring washers are , (most probably) best.

[carsy]

phazed said:

Been there etc.

I've come to the conclusion that the original 9/16ths head steel bolts with new spring washers are , (most probably) best.

Have to agree.

[bobfather]

I've read it on here that spring washers loose their 'spring' when used at such high temperature. I like the job done by one of our TVR folk where he drilled the bolt heads and locked them with wire to prevent loosening

[andyy]

I use them with stainless spring washers
They don't come loose and they haven't sheared off
P.S I dont work for ARP!

Regards Andy

[stevesprint]

Andy
Thanks, What's the longest you've used ARP Stainless steel exhaust bolts and then removed them?

Bob
You're right, my spring washers are completely flat after 6+ years.

Peter
Thanks for your suggestion, do you have a spring washer preference, sorry to be pedantic.

[phillpot]

in my humble opinion....................

[lancepar]

My ARP's came with the car so I've used them with Nordlocks on the Chim' rebuild, If they come loose i'll change em.

[Loubaruch]

Stainless seems to be a popular option for exhaust bolts/studs but I would not touch them.

Apparently stainless performs very well at low temperatures as it is cryogenic but dislikes high temperatures and particularly dislikes cycling between low and high the exact environment around the exhaust manifold.

A mechanical engineer who deals with stainless fabrication every working day advised me strongly to avoid them.

[andyy]

I've been using them for 10 years on the Griff and probably removed them 5 times.
Prior to that I used them on a 400se for 4 years and removed them a couple of times.

I also use the bigger washer shown in your picture.

Not got a clue about the properties of stainless steel and its dislike of heat but is a cylinder head really getting 'hot'?
Its not like 800 degrees is it?

[phazed]

bobfather said:

I've read it on here that spring washers loose their 'spring' when used at such high temperature. I like the job done by one of our TVR folk where he drilled the bolt heads and locked them with wire to prevent loosening

That was Simon, (Sardonicus)

[Sardonicus]

No chance of those ARP bolts causing issues running into the ally Stevesprint I have witnessed the flange bolt issue on a guys car I worked on but put that down to the fact they are a lesser/cheap quality than the ARP kit and ARP have rolled threads instead of cut threads however I think the standard bolts with suitable Nord locks etc are far better suited to this job so am with Phazed and Carsy on that one , I use these but I didnt drill they come pre-drilled from the states as a kit