Head Studs Vs Head Bolts

[ripps]

just wondering everyone thoughts and opions on what to use head bolts or arp head studs? Also why you have gone the way you have thanks fellas

[JonnoHR31]

if you can afford it studs are better. depends on budget and power goals etc

[ripps]

power goal will hopefully be about 370-380kws

[JonnoHR31]

if you can afford it they'd be a good idea. otherwise new stocker bolts should do the job fine

[Aberax]

As a lot of people would say "Do it right, Do it once", use the ARP Head Studs, they aren't too expensive either, $170-$250 delivered from the US.

[jangles]

thats right, for that power goal, the extra couple hundred shouldnt be a big cost

[EdGTR]

This is also a question i have been asking my self and the reasons i have come up with apart from the fact that thats just what you do, has to do with the way the threads pull and the length of contact area is better having studs than bolts. Also alot of other really high performance stuff run studs standard, mostly bikes but its still a engine.

I hope that gives you a little reasoning even if it still comes out as do it once do it right. I will use them on mine when the head comes off.

[boostn0199]

I just got a few questions about the ARP studs, ive heard you need to re torque them after like the first 100km and that you cannot get to them without removing the cams is this true?

[jangles]

I just got a few questions about the ARP studs, ive heard you need to re torque them after like the first 100km and that you cannot get to them without removing the cams is this true?

cam covers yes, cams no. most heads are assembled then put onto a block and torqued down?

so i dont see as to why the cams would need to be removed

[Aberax]

cam covers yes, cams no. most heads are assembled then put onto a block and torqued down?

so i dont see as to why the cams would need to be removed

That is true, but in some instances it may not. It depends on the Cams you are using, most will have a notch taken out, that when you rotate the cam will allow access to the head of the bolt/stud, some cams may not have that notch.

[EdGTR]

I undid a set on a 25det that did have the notches and even with those we had a get a deep thin walled double hex (12 point) socket to suit (from memeory it was half inch) and with that we still had to grind it down a little but it worked. On the same subject does any one know the correct tension to do the studs up to in the block and should the threads be oiled? also do you use the same tension for the nuts as you would for the original bolts?

[JonnoHR31]

stock 25 head bolts are 10mm hex, i used a 10mm allen key with the short end cut off then a 10mm socket on that, worked very well and had no troubles with the cams in.

studs do not get torqued down into the block, hand tight only iirc. and yes use the standard torque settings for the nuts, the extra clamping force comes from the different thread design.