Head bolts: You decide.....

[oldeskewltoy]

I've been aware for about a decade that ARP head studs in a 4AGE are NOT something you need to bother with... I've heard this from Loynings on many occasions. Well, now from the "other" 4AGE engine gurus... Hasselgren speaks

from another forum Wrote:I have quoted the reply from Paul Hasselgren. Basically the ARP studs may represent a problem. He has some useful insight so when you make a decision about what bolts/studs to use I strongly recommend you consider the oil galley issue. My thanks are extended to Paul and Chester:

"Hello Alastair,

The oil does flow past the stud as you have observed, are you still using the VVT pulley? We restrict the oil flow on the race engines but for the street you need idle lubrication for the cams and tappets.

I think the ARP studs should be waisted to the minor diameter of the threads at the body of the bolt leaving a centering step at the top just like the standard bolt, which worked well for us past 230 hp and 13/1 compression, we never did use studs until we started turbo charging.

Paul Hasselgren
Hasselgren Engineering Inc."

oldeskewltoy from another forum Wrote:if it makes you feel any better... Loynings only NEEDS the ARP when the engine is a structural member... conventional builds will often times get bolts

When 2 reputable well known engine builders tell you you don't need something..... but you buy it anyway... what does that tell you??


(PS I posted this here... I had thought in the 4AGE engine info thread... but that is stock stuff... not modified)