ARP Studs

[TurboProject]

bit of an update for this old thread...

I just ordered 8 of the long studs direct from ARP. They were $12.25 each and were instock ready to ship. I already had the 3.4L iron head set with hex nuts from when I was going to build an iron head motor. I'm now building a 3500/3.4L hybrid so I can use half of the iron head bolts, the washers and nuts from that kit, plus these 8 longer studs. A bit pricey but cheaper overall since I already had this other kit.
Thanks for that part number! It came right up with ARP.

[SappySE107]

I sell the head stud kit on the wot-tech site as well. I can get half kits if need be for less than 12.25 a stud.

[TurboProject]

Doh! Oh well...

[gectek]

not always smarter to reinvent the wheel

[TurboProject]

I figured the "wheel" as you put it was the whole kit. I took that to mean that individual studs were not available through WOT Tech and that from there my only option was to go direct to ARP. Little did I know Ben would be willing to order individual parts just for one person. I wasn't trying to buy a whole kit since I didn't need the full $190 kit from WOT-Tech. And 12.25*8 is still considerably less than $190. I'm looking at the bottom line on this issue, not value...

[gectek]

well if he assembles a kit, then ideally he can sell individually as well.

[TurboProject]

well then just call me an a$$ for a$$umming...

[gectek]

no....not that. i have done it as well lol

[gectek]

i do it too. you know now lol

[TurboProject]

Another little problem...I got my longer ARP studs(it looks like they actually gave me a slight discount) and these studs are undercut where all of the ones in the original iron head kit are not. Is using half undercut and half not undercut studs going to be a problem? Are all of the ones in the 3500 kit on WOT Tech undercut?

[sprucegagt]

Another little problem...I got my longer ARP studs(it looks like they actually gave me a slight discount) and these studs are undercut where all of the ones in the original iron head kit are not. Is using half undercut and half not undercut studs going to be a problem? Are all of the ones in the 3500 kit on WOT Tech undercut?

I believe the undercut studs due get torqued to a different value than the non-undercut studs. If they are the same length and size.

[SappySE107]

They are undercut, and I am not aware of a difference in torque for installation between undercut and non undercut.

[TurboProject]

Taken from: http://www.centuryperformance.com/fa...h-spg-139.html

"Undercutting:

Reducing the shank diameter of fasteners reduces head gasket sealing problems. Short fasteners are very stiff and the amount of bolt stretch available is about the same as the amount of compression in the gasket. Should the gasket lose some of it's compression due to set, it can quickly eliminate the pre-load (torque) in the fastener - which will unload the gasket. This results in a blown head gasket. Providing optimum stretch is absolutely critical. Using an undercut stud helps control head to gasket clamping force better than conventional studs."

Not that the shorter studs in the 3500 application are all that short, so it may not be that big of a deal. Maybe since the 3500 top end allows it, I could pop the valve covers and retorque them after a few warm-up cycles.

[gectek]

will not be a problem at all. the undercut stud is supposed to be stronger. this coming from ARP themselves

[sprucegagt]

I always thought that there would be a difference in bolt stretch if length and size were the same. But if ARP says it's fine, then so be it.