ARP told me I could leave out the washers or back the studs out a little. I also consulted my machinest who builds a lot of high performance engines. I gave him the dimensions of the stud including the thread length, how much the stud needed to be backed out from the bottom of the hole and he said there was far more thread then needed in the block. His comment was to use the allen at the top of the stud to adjust the height of the stud to match the top of the nut. He says he has to do that on quite a few engines (many different makes) using studs and it has never been an issue. Since this guy has forgotten more about engine building then I will probably ever know, I went with his suggestion. He has never steered me wrong before.
<= s52 block.
? You torque the nut no matter what. There is always friction on the nut? I don't get what you are saying here. You also compress the assembly no matter. Torque is torque. 65ft/lbs is 65ft/lbs.
I don't know what you are saying. It's like saying 65ft/lbs of torque on a bolt is different than 65ft/lbs of torque on a stud. It's not. Please explain!!
For example, you could use the allen hole to secure the stud while you torque???
Don
My mistake I don't know what I was thinking - I forgot how new studs should just thread down. It'd only pose a problem if reusing and the threads stretched at all.
I just think its a better idea to not use the washer - the head flange of the nut is literally the same size of the washer - they're both hardened, so they're both going to press down on the surface equally. The washer slipping on the cap or nut slipping on the washer is going to create friction necessitating the moly lube, so I wonder if ARP includes washers for the sake of including them or what. They can't hurt, but I am convinced they're not necessary.
ya know i honestly don't see the real benefit from using the ARP main studs anyway. what is the real benefit?
do you even know what a plethora is?
higher grade stud, re-useable, havent delt with my bmw block yet, but studs > bolts im assuming bmw stock used bolts
from what i was told you dont NEED to bottom out the stud, you actually want the stud to push and pull if you know what i mean
i've also heard of people putting ball bearings down in the hole
last time i used arp's (aluminum honda block) i got nervous because the last few torque downs i seen the stud turning not the nut.. i was going 10+ ftlbs over what my manual said which is common from honda-guys i know of.
motor held 12psi beaten daily with a $45 fel-pro mls head gasket so i guess it was ok. on top of that i used a used head on a used block from differnt years and didnt resurface either. maybe i got lucky lol ahh good old days, cheap hondas
side note, maybe arp inlcudes washers for the simple fact its probly easier to remove the nuts when needed?
Last edited by 7808; 02-26-2008 at 05:53 PM.
Reviving this thread! I want to know what the consensus is now. The way I see it main bolts now cost $103 and ARP studs are $130 0n sale through ecs tuning. The way I see it you can back the studs out 5mm and use the washers except where the oil pickup brackets are located, or bottom them out and not use the washers but back out the studs that hold the brackets. I also read somewhere that when running the arp main studs you need to torque it and have it honed which at this point I am not going to do. I am using a M52 block for a 3.0 stroker. The main reasons I am considering the ARP's is because I want to be able to reuse them, they are so close in price, and also hope to run boost down the road.
Gotta cut up the oil baffle as well.
1996 332IS
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Baffle delete. S54 pan and pump going in.
just put the studs in my new motor and i can confirm (as i contacted ARP) you back the stud out so that it is flush with the washer and nut on. Worked fine and the motor has been running great.
Whats behind you doesn't matter
Black E36 M3 - Blackbird
Silver 2007 New Body 2500HD - The Judge
Yes the dual pick ups and there are a front and rear sump. It also has extra holes so running a turbo drain would be easier. Increased oil pressure as well from what I have read. But the biggest reason I bought it was I don't have a spare oil pan and the pan and pump were $400 much better then getting my m50 pump rebuilt. It's got around 60k on it so I think it'll last awhile.
Does anyone know the specs on these studs? I have a 3 cylinder diesel pulling tractor and these are the studs i need.
Does this help?
https://arpinstructions.com/instructions/201-5000.pdf
One issue I haven't seen mentioned in this thread is the fact that the ARP stud always has a fine thread on the nut end, as opposed to the coarse thread that goes into the block. For that reason the slope of the thread is much flatter on the nut end, so you are not likely to be able to significantly turn the stud in the block.
There's also the matter that the same thread difference causes a difference in the clamping force for a given torque value. As an example, an engine I have worked on was available with bolts holding the heads until the last few years when the manufacturer switched to studs. The blocks were machined the same with coarse threads, but the studs had fine threads for the nuts. The factory spec for bolts was 75 lb/ft, but the spec for the studs was 55 lb/ft, roughly 25% less. The clamping force was identical for both. So if you install ARP studs and torque them to the same value, the clamping force is over a third higher! You might want to be sure you aren't distorting the main caps with them torqued down that way.
Marty
Yeah, ideally you want the same fasteners and torque specs that the block was machined at (head studs torqued while boring, main caps torqued while honing). My engine builder lost his mind and vanished so when I rebuilt the engine last winter, I didn't have any references but the mains were changed to 11mm. I found the ARP part number and they were for a Chrysler application and spec'ed at 75 or 80 ft lbs I forget. I tried torquing to that and bore gaged the mains, they ovalled like mad - I would have had like 8 tenths of clearance. I ended up around 60 ft lbs where the main bores stayed round.
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