Has anybody on here gotten, or looked into getting ARP head studs??

 

I'm wondering what sizes I would need to get... what thread pitch, lengths, etc...

Not sure on the length, but the threads are M11x1.25

Per head there are:

 

4 bolts x 118.5mm long

9 bolts x 132.5mm long

 

All thread pitch M11x1.25

Where are you getting them from Tex?

Ask Rallyruss

Got through to a person at ARP this morning. I need this info:

 

The thickness of the head where the bolt holes are. Both the short and the long holes.

 

I need to know how deep the threads go into the block, and also how much dead space there is in the hole before the threads start.

 

I already know the size and thread pitch.

 

Once I am able to give him these dimensions, he'll be able to give me a price.

 

Any help would be appreciated. Not sure if the FSM's would have this kind of info.

the ea81 studs are 11 x 126.5 x 39

 

they might work for the shorter ones

Measurements I took from my block with my Vernier Calipers.There are 2 sizes of studs needed. 9 per head for a total of 18 studs. I need 6 smalls, and 12 bigs.

SMALL:

A. 14mm

B. 25mm

C. 76.5mm

D. 12.7mm

E. .043" (although, I would potentially like the oppurtunity to run a thicker copper gasket in the future)

F. 8mm

G. 24mm

H. 44.5mm

I. M11x1.25

BIG:

A. NA - no counter bore

B. 25mm (not really a bore, but the space allowed for clamping/washer space)

C. 90.5mm

D. 12.7mm

E. .043" (see note for small)

F. 8mm

G. 24mm

H. 44.5mm

I. M11x1.25

These were taken off a neat sheet the ARP guy sent to me. I'll see if I can fill out a little legend for these.

A. Depth of Head Counter Bore

B. Diameter of Head Counter Bore

C. Thickness of Head from the bottom of the counter bore to the bottom of the head

D. Diameter of bolt/stud hole in head

E. Head Gasket Thickness

F. Depth of counter bore in block (space before threads start)

G. Length of thread in block

H. Depth of bolt/stud hole from block surface to bottom of hole

I. Thread size and pitch

I got a response back from the ARP guy. He has off the shelf studs that will work for the 6 small ones. He's getting me a quote to have the big ones custom made.

thats about what I found out. sorry for not chiming in sooner.let me know if they will make the long ones for you. I would be interested in some. they are not cheap but the quality great.

yes, let us know what they say in terms of price for the longer studs. If it helps, maybe we can get a few people together on this and do a group buy thing.....

 

garner

Per head there are:

 

4 bolts x 118.5mm long

9 bolts x 132.5mm long

 

All thread pitch M11x1.25

 

Wait, shouldnt that be 3 short and 6 long per head?

Ok, i see that was addressed up there... :-p

 

I am certinly interested as well. I want some freaking 100 ft-lbs holding the head on...or MORE.

Oh, and are we going to beable to re-use the studs? Say...if I TOAST a block that I have them in, am I going to beable to get the studs out easily and install them into another block?

they are not stretch studs so there should be no reason that you cannot reuse them. they are probably better for reuse than a standard head bolt.

GOOD.

 

I am idlely looking to do TD04 soon.

If there's a group buy I'd like in, for two sets.

Anybody know an approximate price, like how much for the available short studs?

The guy i'm working with at ARP is working up a quote. It should include the cost of the off the shelf small studs, the custom made long studs, and the needed nuts, washers, etc.

 

I'll post it here when I get it... and I'll ask about doing a group buy then, if there is serious interest.

I would say be ready to pay over 200$ for a complete set. but making the custom order may raise that a bit. this is just from what I learned from dealing with ARP.

Is there a way to find out what they "stock"? Or do you need to contact the company and ask specifically?

 

As mentioned in an earlier thread, I would be interested in stepping up to either 12mm or 13mm/0.5inch studs. A little better holding power, and perhaps more common size.

 

$200 is a chunk of change, but like they say, "How fast do you want to go?"

What I had to do is call them and ask if they had any for my application. Of course, they didn't, so they faxed me this dimension sheet and told me to email or fax it back. Did that, and the guy told me they have ones that will work for the small bolts, but not the large. Since my email server is down, I won't know till Friday if then what the quote on getting the long ones custom done.

 

I was going to inquire about going to a bigger stud aswell, however i doubt the cost would negate the cost/effort of drilling retapping the block.

why not find out whats the next biggest size stud, and get those, then when one gets their block trued get them to drill/tap for that size? might be a little cheaper

the holes in the head may need to be drilled larger to clear larger studs. its a little bit close.

rather than go larger you can install thread inserts/helicoils that are 7/16" and those studs may be mor easily found.

that is of course if we strike out on the custom order for the larger ones.

they never offered me that option when I talked to them last time. If they can do it for tex that would open up a great option for EA82T building. studs would really help a high boost aplication. I think what he is working on is really the best thing.

Ok, I got my quote back:

 

The 6 small off the shelf ones are $10.60 a piece. Total for these is $63.60.

 

The other 12 studs would cost $593.25. Most of this I'm told is the setup cost. He will be getting back to me with a quote for 3-5-10 sets.

 

Oh, on top of that, add the cost of nuts and washers, which I haven't gotten yet.

 

$593.25 + 63.60 = $656.85 total for one set of studs. Nuts and washers extra $.

 

A little bit out of my price range. I'd realistically be willing to pay $200 or so for a set. We'll see what the results are from the multiple quantity quotes.

 

As I can't wait to get my engine together, I went ahead and order brand new head bolts. $2 a piece from 1stsubaruparts.com. Should be here late next week, or early the week after. This doesn't mean I am giving up! I will still take this contact as far as I can. Atleast get the info out there for others.