ARP Head Stud Sizes?

[2ndGenGuy]

Does anybody know where to get a listing for ARP head stud sizes? All that I can find on their site is their catalog with part numbers and about 5 applications. It would be nice if they listed the length, thread, etc. I would like to get some ARP studs or bolts before I redo the motor in the hatch.

Honda's website says it's a 10x112 bolt. I know 10mm is the OD of the threads, and 112mm is how long the shaft is.

Even a nice listing of stock bolts would be nice. The OEM parts listing is pretty damn vague. I'd hate to have to send one in to match it up after I pull it out...

[1GCustomAccord]

Does anybody know where to get a listing for ARP head stud sizes? All that I can find on their site is their catalog with part numbers and about 5 applications. It would be nice if they listed the length, thread, etc. I would like to get some ARP studs or bolts before I redo the motor in the hatch.

Honda's website says it's a 10x112 bolt. I know 10mm is the OD of the threads, and 112mm is how long the shaft is.

Even a nice listing of stock bolts would be nice. The OEM parts listing is pretty damn vague. I'd hate to have to send one in to match it up after I pull it out...

I think that part number is 90005-671-003
10 is the diameter, 125 the length, and the thread in milimeters is 1.25.
EDIT: The length is 112 milimeters.

[2ndGenGuy]

So the 10mm diameter... is that the same as an M10 bolt? Could I just call ARP and ask them for an M10 stud that's 112mm long w/ extra length for the nut on top?

[Ichiban]

Should be able to send them a drawing with overall length, length of lower and upper threads, thread pitch and size. Get them to send you nuts, too.

[2ndGenGuy]

I'm not sure how long the lower threads are. Anybody have any bolts sitting around they could measure? I used to have a huge bag of them, but I'm not sure where it disappeared to. I would just send them a whole bolt if I could find the damn things. Would it hurt for the threads on the new bolts to be longer than the threads in the block?

Don't I want the studs to be long enough to bottom out in the block? I assume that would mean they need to be longer than the bolts themselves, since those shouldn't bottom out, but merely tighten on the cylinder head... Or am I way off?

[1GCustomAccord]

So the 10mm diameter... is that the same as an M10 bolt? Could I just call ARP and ask them for an M10 stud that's 112mm long w/ extra length for the nut on top?

The "M" designation stands for metric, as explained here, http://euler9.tripod.com/bolt-database/22.html

The length is measured from the end of the thread to the base of the head, not the entire length of the bolt.

You can show them this picture:

Thread size: M10x1.25 x 112 mm
Head: Double hex
Strength: Unknown, maybe is 10.9, not sure about that.

[2ndGenGuy]

Ah man perfect!! Thanks so much for your help!!

[1GCustomAccord]

Attention, you need to use the correct washers on those bolts, so they dont bottom out.
The original measure is: 23x11x2.3
PS: You are wellcome

[2ndGenGuy]

Buh so if the head is milled, do I need a thicker washer?

[1GCustomAccord]

Buh so if the head is milled, do I need a thicker washer?

Sure, if you want add to the washer the amount of milling done, thats only needed if the milling is big, lets say, 0.3 mm or more...maybe more. I never had problem even with very milled heads.
Can you tell how much your head have been milled?

[1GCustomAccord]

Well..this is interesting.
I just performed a test: I installed the head in the motor, WITHOUT the head gasket and WITHOUT the washer, and i was able to FULLY thread in the bolt untill the head was firmly pressed in position.
Note that i only inserted one screw, not all of them, so to make sure i guess that all the screws must be tested this way, but i think i can say as the Mythbusters says: That myth is false.

[2ndGenGuy]

Cool, so no worries about bottoming them out pretty much? I imagined that they would have left lots of leeway in there. I'll go through my receipts tomorrow when I get home and see how much they milled. They also decked the block too.

[mushroom_toy]

That headstud looks the same as the A20 one, Ill measure one of mine, and if theyre very close or the same then you can just use the miata arp headstuds.

[2ndGenGuy]

^^ Thanks man! It's all good though, I tried to compare online already and they're definitely different. The A20 is 11x140 or something like that. I was really hoping they would be the same. Your build thread totally reminded me about the head studs!

[79cord]

Wasn't all that extra spiraling Honda added down the length of the stud supposed to have been introduced to help them stretch a little to accommodate overheating expansion.
Is it used on "normal" aftermarket headstuds?

[1GCustomAccord]

Wasn't all that extra spiraling Honda added down the length of the stud supposed to have been introduced to help them stretch a little to accommodate overheating expansion.
Is it used on "normal" aftermarket headstuds?

Did you confirmed that fact? I always tought that the spiral in the middle is to "pump" dirt out when you unscrew the bolt, as the extra spiral is inversed.

[2ndGenGuy]

I always heard they were there to reinforce the bolt so that it won't stretch.

[1GCustomAccord]

I always heard they were there to reinforce the bolt so that it won't stretch.

Interesting fact, as the shop manual says nothing about replacing the bolts when reinstalling the head.
Maybe they were designed to be used several times without need replacing.

[Ichiban]

Maybe they were designed to be used several times without need replacing.

Yes they are. Torque To Yield bolts can be distinguished by the torquing sequence. (these are the non-reusable ones) TTY bolts will be torqued to a specific value, and then rotated an additional amount, ie 3/4 turn. Normal, reusable bolts will be torqued to a value, usually in stages, and left there.

Always remember to measure reusable bolts for excessive stretch, and never torque a dry fastener.

[2ndGenGuy]

Always remember to measure reusable bolts for excessive stretch, and never torque a dry fastener.

Hmm! Don't think I did this. We may be onto something.

[2ndGenGuy]

I e-mailed ARP today. Got a response back in a few hours (Those guys rock!)

You should be able to use kit # 208-4305 that kit has (10) 10mm studs with a overall length of 5.700” the kit also has nuts and washers

Turns out they are head studs for a D16Y engine! Freakin' sweet!

[1GCustomAccord]

I e-mailed ARP today. Got a response back in a few hours (Those guys rock!)



Turns out they are head studs for a D16Y engine! Freakin' sweet!

Pics???

[2ndGenGuy]

Don't has them yet. I will post pics when I get them. Just ordered them today.

[1GCustomAccord]

Bumpy! No picture yet?