You probably already know but If you do go ARP head studs DONT follow the directions supplied as to torque rates.

Even if you might get them from a miata centric supplier and might presume, in your haste, that the instructions would be appropriate.....(which was the source of our mistake)


The instructions don't say it but are not the required aluminium head torques (which are considerably less).

just a just in case.

 

Yeah I didn't mention those in my mod list, but I went with 20lbs, wait 15 minutes, +20 wait 15 plus 20, so 60lbs total over 45 minutes, I'll be doing the same procedure this time around.

 

Might pay to double check that value. I have a feeling that was what we went with and ended up with oval bores and started belching oil over 6000 rpm, amazingly the dyno tuner picked the problem.....buggered if i know how he knew...

I could be wrong but 45 seems to ring a bell....search the internet to be sure, a few people have done the same thing so its mentioned quite a lot.

 

55-60 is the correct Mazda OEM value.

ARP states 80. DON'T do that!

 

You are correct, when I searched I found people who went full ARtarded at 80ft/lb and some people went with 45. I THOUGHT 60 was a safe bet, but I'm open to conclusive data.

There are words of increased torque/torque exerted due to a decrease in stretch between OEM and ARP build material. That's definitely plausible, makes a lot of sense, which makes 45 a logical choice, some people however are using 80ft/lbs with good results, others are cracking bosses. So I really have no clue what to go with.

 

well we didn't damage anything, that im aware of but we did oval the bore so the dyno tunign didn't go well.

Car started breathing out the vents and dropping power at 6k. Was wierd 6k every time and the tuner after the 3rd time actually predicted what was happening right off the bat.

Best 100% diagnosis I have ever seen!