First off, please don't give me shit about repeat threads, it takes 10 second to reply this post.

I know what I'm going to torque my head stud nuts to.

I'm looking for specs on what to torque the stud into the block.

Much obliged

I'd say 190-200 ftlb....since it takes like ten seconds

I believe "finger tight" is the spec you're looking for. There's a allen key fitting on the end of the stud, I always just snugged it down with that, but my shit always blows up so maybe don't do that.

a few kilograms

go to the product source...

ARP | The Official Web Site

Finger tight.
There is a video somewhere with an ARP rep saying why exactly.
Basically don't want and side load on the stud. Just a staight pull. By only going finger tight in the block the stud still has fredom to move around allowing the nut and washer to determin the "straight pull".
Something like that. :2cents:

Your were correct, thank you. But I'm wondering why they want 80ft lbs? I'm not going past 60, nope nope nope

Thanks for the link

You're going to use an ARP product because they're superior, but choose to ignore their instructions?


Curious choice.

Not so much ignore just weary of cracking my head, I did it to my 99 headed following those instructions. I think this time I'll split from factory to the ARP suggestion and just do 60

There's no way possible that torquing those studs to ARP's specs in the proper manner will cause your head to crack.

On the contrary, torquing ARPs to factory specs can and will probably make your head gasket leak.


If you're going to use factory torque specs, then use factory hardware.

ARP torque spec of 80 for a 7/16 bolt with moly is just rediculus. and I can say it can and did crack a head. The Miata aluminum head under their tiny washers squishes with permanent deformation with that much clamp load. 20 to 30% increase in effective clamp load over stock is probably Ok more than double is silly.

Weird. I took the set on the f2 to 100ftlbs, miata to 80. No issues.

This thread:
https://www.miataturbo.net/engine-pe...e-miata-54746/

it takes 10 seconds to search

you just think you're special

Wow, I might as well close my eyes and turn the wrench based on all this confusion. There's too much bullshit on most of these threads.

I'll go 70 and just trust my intuition

Torque spec? ALLOFIT

so let me get this straight:

-you ask a question that has been discussed and easily found
-you tell everyone to spoon feed you the info cause you're too special to adhere to the rules everyone else does
-you call people out
-you conclude the thread with calling everyone a bs'er

Congrats. I don't think you coulda been more of a douche if you actually tried.

By the way: to all those that spoon fed him - this is the direct result of your spoon feeding, self entitled douchenozzles that will never actually learn

I did 78 ft lbs. I thought I read from either Emilio or Andrew about not going over 85 or something like that. Don't quote me on that but it's what I recall. I figured that was close enough to 80. + The lube on thread and nut and washer I figured that was plenty.

Thanks for your input. I did 70 with assembly lube.

Listen guy, you've been up my ass since I've started this forum. I've done nothing but ask questions and all I get is shit from you and a select few others.

I don't care how many times a question has been asked and discussed or how many thread repeats I create. There is always someone new to input their thoughts. Novelty to a stale topic and that's what I look for when searching for answers on a forum.

It apparent so far that every newbie or junior member has positive input to my questions and most of the senior\elite I've encountered have bitterness and insults.

What the hell is a Hear Stud?

This thread is now about SCUD

TL;DR
Take a German V2, make it simpler, put it on a truck, make a million of them

http://upload.wikimedia.org/wikipedi...-scotland1.jpg

Scud is a series of tactical ballistic missiles developed by the Soviet Union during the Cold War. It was exported widely to other countries, in particular third world countries. The term comes from the NATO reporting name Scud which was attached to the missile by Western intelligence agencies. The Russian names for the missile are the R-11 (the first version), R-17 and R-300 Elbrus (later developments). The name Scud has been widely used to refer to these missiles and the wide variety of derivative variants developed in other countries based on the Soviet design.

https://www.miataturbo.net/attachmen...ine=1408167551
(I've been to this museum when I was 6)

The first use of the term Scud was in the NATO name SS-1b Scud-A, applied to the R-11 ballistic missile. The earlier R-1 missile had carried the NATO name SS-1 Scunner, but was of a very different design, almost directly a copy of the German V-2. The R-11 used technology gained from the V-2 as well, but was a new design, smaller and differently shaped than the V-2 and R-1 weapons. The R-11 was developed by the Korolyev OKB[1] and entered service in 1957. The most revolutionary innovation in the R-11 was the engine, designed by A.M. Isaev. Far simpler than the V-2's multi-chamber design, and employing an anti-oscillation baffle to prevent chugging, it was a forerunner to the larger engines used in Soviet launch vehicles.

https://www.miataturbo.net/attachmen...ine=1408167551
DAT ASS

Further developed variants were the R-300 Elbrus / SS-1c Scud-B in 1961 and the SS-1d Scud-C in 1965, both of which could carry either a conventional high-explosive, a 5- to 80-kiloton nuclear, or a chemical (thickened VX) warhead. The SS-1e Scud-D variant developed in the 1980s can deliver a terminally guided warhead capable of greater precision.

All models are 11.35 m (37.2 ft) long (except Scud-A, which is 1 m (3 ft 3 in) shorter) and 0.88 m (2 ft 11 in) in diameter (DAT GIRTH). They are propelled by a single liquid-fuel rocket engine burning kerosene and corrosion inhibited red fuming nitric acid (IRFNA) with UDMH, unsymmetrical dimethylhydrazine (Russian TG-02 like German Tonka 250) as liquid igniter (self ignition with IRFNA) in all models.

The missile reaches a maximum speed of mach 5.

You're not special, cupcake.
Learn to search like the rest of the peasants

I just torque it until I hear a loud crack sound, then I move on to the next one and repeat until I'm done with all. Has worked great on the 50+ heads I've gone through! That means I have lots of experience with this

Auto correct dicked that up on me

Don't want to be special. I just don't have time to sit around and search through the 24 pages inside of the 2600 thread inside 9 topics, just to question who is full of shit and who knows what they're talking about.

A newbie member with 2 total posts maybe the best engine builder this site has ever seen and a member with .. Say, 18000 posts may be an incompetent tit with regurgitated information.

So numbers and member title mean nothing on any forum.

So far I've met 2 members I can trust and it's because I know their background and what they do.

It also takes 10 seconds to call ARP and get their recommendation. It also takes 10 seconds to read the data card that came in the box with the studs. Why did you start this thread again? We get angry about repeat threads because it makes it harder to search of the information we are looking for. The signal:noise ratio on this site is still pretty decent and we aim to keep it that way.

What makes you think we have the time or desire to explain again what has already been hashed out over "24 pages inside of the 2600 thread inside 9 topics?" Most of us don't know this shit off the top of our heads so to get the answers we need, we are forced to do the same thing we are telling you to do: we search for it. Why would we take the time to do something for you when we know you have the same tools available at your fingertips?

As to who is full of shit, everyone is full of shit. This is the goddamn internet, are you new here? We already know who is full of shit and who knows what they are talking about because we don't just come here to mooch knowledge, we participate and engage in lively discussion on a daily basis. This is where the guys with the 1k+ post counts come from. Read and follow along and participate. Don't just barge in here, demand help and then get butthurt when we decide we don't want to spoon feed you. We have invested the time to be participating members here on the forum, why is it unacceptable for us to desire the same of you?

Also, dude... I'm not sure I would trust the word of a bunch of random dudes on the internet about torque specs for an engine build project without spending some significant time verifying that data.

Great! I'm sure they warned you about this place too. Join the "community" here at MT and get to know some more people. I briefly searched back through your post history and discovered you are in the middle of naturally aspirated PTE type build that I'm sure a lot of people would love to read about. Go start a build thread and link it in your sig. Fill it with pics and tell us all about your plans. We will be much more likely to help you after we get to know you. It's not that hard, this isn't rocket SCUD surgery.

Above thread should be a must read for anyone using ARP fasteners - All 4 pages.

Its interesting that ARP has a "one size fits all instruction sheet" that just does not work for the BP cylinder head. Torque to yield should be the stud or bolt not the head casting...

You know, I think your right. I will compile a write up and post it.

Your also right about expecting answers, my apologies.. Sometimes I get too busy to take the time. I figured inside this forum there is some one with the knowledge on hand or knows it well.

Thanks for that. I had not come across that before. I won't be exceeding 65 fl lbs in the future.

For what its worth I've done the 3-step method (30lb, 45lb, 60lb) on at least 2 BP's with ARP head studs with great results.

Thank you. My process wasn't too far off 30, 50, 70. I just got it running about an hour ago. So far it appears to be good, but I won't know for sure until either dyno day or my next race.

We did the same maybe 56lbs if I recall Sav's post...

Not as curious as you might think. IIRC it was FM who worked with ARP to get those studs made. Their original torque spec was 49ft.lbs, which matched the factory clamp load. When I bought my first set in 2009, the instructions said 65ft.lbs, so that's what I did. I installed several sets at that setting before looking at a fresh set of instructions somewhere around 2011-2012, and to my surprise they said 80ft.lbs. A little forum reading turned up Bob's experiences with cracked heads at 80ft.lbs. Clearly, the engineer at ARP who said 49 is no longer there, and ARP doesn't care enough to put thought into their specs beyond "X diameter + Y thread pitch = Z torque".

I torque ARP studs to 65ft.lbs.

Good to know, thanks sav.

I just did a fresh rebuild with ARPs. Haven't even fired it up. I torque to the sheet indicated 80. Any reason to undo it and go back to the 65 since nothing bad happened?

If it did any damage, it's already been done. Go with it and hope for the best. 80 sounded way to high, I torqued mine at 70 which is 5 pounds over factory recommended and I'm nervous to see what happens. I will report back with the result of the tune.

I sure as hell wouldn't "untorque" it now. Run it! I'm sure it's fine, although after what Sav said I think I'm going to be torquing mine to ~65/70 when i finally toss this motor together.

Sort of unrelated but has anyone ever heard of a boosted Miata lifting a head? Or blowing out a head gasket under high boost?

Are OEM Head bolts totally sufficient for 99% of the builds on this site but people are using ARPs because....they're ARPs??

Are head studs the answer to a question no one really should be asking?

I understand the benefit of the head studs for ease of cyl head installation and don't doubt that that alone makes them worth the money.

I'll hopefully be installing my head in a few days and I'm trying to decide if I NEED to order ARPs, should buy new OEM bolts, or just reuse the head bolts I have. I know Sav tried to reuse some head bolts with NG results, but others seem to have no problems reusing stock bolts (including lots of SM engines?).

What do you gehs think?

From everything I have read we just use ARP head bolts for ease of swapping heads. I have personally done about a half dozen head swaps with reusing stock head bolts and have never had an issue. Braineacks miata ran for 18k miles boosted at 240hp with reused stock head bolts.

Yep, that's what I gather too - confirmed re-usability with ARP vs you really shouldn't re-use the stock head bolts, and if you do, the proper way to do it is measure/check for stretching/etc.

Stockers work though. So there's that.

It's all based on recommendation. The stock bolt technically have to be measure for stretch after they are torque and taken off and changed. So If you need a new set of stock head bolts, I am sure the price difference is not much if any from ARP. And if you are spending lots of money on the engine, what is extra $100 to make sure you don't have to deal with BS?

I don't have a FSM in front of me, does Mazda recommend reusing the head bolts? Is there a published spec for checking the bolts for reuse?

• Rosenthal has head bolts for $12.82/ea so that's $128.20 before shipping and tax. No washers, no lube.
  
• Trackspeed has ARP studs for $129.00 before shipping and tax. With washers, with lube.

Same price? I'm buying the ARPs every time.

Probably, but reusing critical fasteners is generally not wise and I'm not interested in being the R&D guinea pig that finds out when stock head studs stretch/break (BTDT with main studs, have the wrecked block/crank/oil pump to show for it). Therefore, I use ARP studs so I never have to worry about it.

I've done about 30min of various Miata ARP torque setting searches all over the net. Read your posts about ARP on other MT threads. Got my numbers set from your posts. Read this one just before bed and this cements it. So now I'll sleep fine especially after the way you worded this last answer.

Torquing the bottom end tomorrow. Heads later on when my shims arrive/are set.

Thanks.

I had the bolt debate with my fabricator I called Arp they said 80 I called fm I believe they said 60. We split the difference but I would suggest a sticky or someone needs to school Arp on there own products. I'm referring to the nuts. As mentioned studs hand tight.

I ran the ARP2000 rod bolts to 60 ftlbs. I ran them to 20 then 40 then 60. I did not have a stretch gauge so I used this method. I'm a bit nervous on this ?

ARP has become fully retarded on what they think the B6/BP Miata head can handle.

I don't know about ARP rod bolts. ARP specs are fine for that you are not going to yield rods with too much torque the critical thing at that location is what the bolts themselves can handle. Mine for Carrillos specify a stretch length rather than torque but I think it was in the 20's. It's the head studs clamping a soft aluminum head that ARP's current specs are too high for. I think they are calling out what the studs can handle not what is appropriate for a Miata head.

My Engine builder is kicking himself as he used the torque setting that came in the ARP box from 949racing.....he used 80 but at the time thought this seems high....

Later on the dyno we had all sorts of weird issues. Seems we didn't crack the head but we did oval the bores....it appears temporarily while under the excessive clamping pressure.

Being a Miata / mx5 specialist supplier, I wish 949 would put a sticker on the box with a warning.

But for the sake of this thread, 80(as per ARP instructions) is way to much. I also think 50 - 60 as mentioned above is more in the proper region.

The problem is no one (or very few) will question ARP suggestions due to the great name in quality products they have....