A1 Studs, Headlift Fix and still lifted - heres why- please read

[Streamln1]

So last week I was trying to get some final numbers on my e16G kit and I got up to 595 awhp on 100 octane at 24psi and started to see some coolant push, so obviously it was time to call it a night. Head gasket was not compromised.

I have A1 Technology heads, and Ray's headlift fix on DR Stage 3 heads.

I pulled the motor apart the other night with the help from one of my engine builder buddies, and we figured out the problem. The washers that A1 comes with are smaller than stock in Diameter, so they had dug into the head slightly leaving an indentation. He had just been down this road with a Supra build and this is a common problem with them and ARP head studs. We are thinking the aluminum had yielded due to the washers digging in. Every single stud was different torque after the lift.

I had religiously followed the torque sequence provided by A1 using their moly lube, and retorqued them after head cycling on it. So torque was certainly to spec and had been checked since.


We think we need to go back to the stock size head washers so it spreads the load out. 105ft lbs may be acceptable, but do we really need to go to 125 with 30 weight?

I am not necessarily blaming the a1 washers on this, because I had ARP's in the past so its likely their washers were also the cause and I had overlooked the indentions into the head, but the A1 washers are still smaller than stock.

I don't think this is a problem that will present itself until 600 and up HP. I CANT be the only one to see this. And ironically their problems start at around 600hp.

See the Supra thread here- http://www.supraforums.com/forum/sho...-Washer-debate

Just a heads up for those who have A1's or ARP's and going for big power, check your washers! Were not helping our matters by defeating the benefit of stronger studs on a smaller surface area.

Edited- A1 Washers are fine, I did compare to stock washers same diameter, im thinking the old ARP kit from years back did this. I will post pics of the double indent from the washers Monday when I go by the machine shop.