www.ka-t.org

Also wanted to show some proof and ease some thoughts on the washer issue. To duncan351's defense his insert washer idea is incredible and I know that it works but after careful research Im certain the bigger issue here is the actual surface area of the washers. The load is just not spread evenly to secure the head with the 10mm washers or 11mm washers that come in standard ARP packaging.

This is a visual representation of the washers available. In the picture are three washers. Top: 10mm and 11mm ARP *They are both the same size I matched them up. Middle: factory Nissan washer Bottom: 12mm RB26 ARP washer. As you can see the 12mm washer is just slightly bigger than the factory washer. I can tell you that after installing they barely fit the bosses of my SOHC head. You can see this in my videos posted previously. Hope this helps some of you. The washer fix has helped 2J, VG, 4G63, and RB guys so it hopefully will take care of the KA24.

KA24ETZTM wrote:I measured a factory head oil galley hole and the stud to get the difference and determine the diameter needed around the stud. Then I measured the 12mm stud and did the math of what drill bit I would need to maintain that same diameter around the stud as was there with the 10mm stud.

what part number used for the 12mm head studs or where did they come from?

They are ARP2000 RB26 Head Studs. Got them from Real Street.

Great additional info on the washer sizes. Makes me wish I would have gone with the RB studs

KA24ETZTM wrote:They are ARP2000 RB26 Head Studs. Got them from Real Street.

Thank You! im in the process of doing this to my dual cam. ive been having head lift issues for the past year. now its time to solve it. is yours complete with no oil issues.

KA24ETZTM wrote:They are ARP2000 RB26 Head Studs. Got them from Real Street.

what did you do about the nuts for rb studs fitting in the hole between the lifters?

ahh you did this on sohc i have dohc

For anyone that did this, and duncan,

I just took a look there is no way the washer insert will fit. Machine shop suggesting to shorten the collar so its able to slip under the bucket castings
Is that what is needed?

You need to machine (drill/ream ) the hole in the head so that the insert part goes into the head. Then it sits flat, just like using the original washer under the studs.

thats understood but i still cannot drop the washer stright down. Its hitting the bucket valvetrain casting.

thats why the machine shop said they will Shorten the "insert part" to slip under from the side of the bucket casting.
Its too tall in the original size to slide in




see picture



Machine shop wants to shorten this part to be able to slide the washers from the lower side of the buckets

Importdude: I was looking at your post and realized the shops who get the big bucks: 1. Bore out that hole all the way vertically to clear the washer (and leave the lifter bucket bore thin in a spot) 2. Or they grind away key areas on the underside of the lifter bucket bore to be able to slip those inserts in.

I think the whole purpose of those inserts is to prevent the aluminum from collapsing in and the entire depth is probably needed to get the benefit from them. If you chop half of the insert off you might be better off saving yourself work and just use the biggest flat washers that will fit.

I checked out the scenario of slipping in a stock washer and flipping it around and it can only flip 3/4 of the way. Maybe there is a tool that can get in there and grind a little of the underside of the bucket bore so you can complete a flip in there. That way you could slide the insert in upside down and then flip it.

Interesting problem that crafty shops probably know how to solve...

^
well, Now I'm in a bind.

Now IF i go with that route the machine shop suggested, I'm wondering if i have enough threads if It sits on top of the factory hole and plus ARP washer then nut

As long as they don't need to remove more than half the length of the insert, it will still work. You won't need the arp washer as well as the insert.

I just had these inserts put into my DE head. I was able to slip the inserts in through the bottom. They barely fit. Took them back out and had the holes cnc’d and then slipped the inserts back in and pressed in.

Fwiw I didn’t need to shorten the collar.

Here you can see the inserts installed in the DE head.