Warning - 1uz vvti Lextreme/ARP head studs

[spf_lexus]

I don't have VVTI on my 1991 but I did use ARP's on mine. What I noticed is that for every set of 20 studs there were 18 long and 2 short... the 2 short ones were supposed to be used under each exhaust gear. I had this issue also. Once tq'ed down with washer and nut the stud was almost perfectly flush with the top of the nut.

 

[XR8tt]

I found the 11mm studs approx 2 turns too short..
No drama though..

 

[crushu]

I have read the whole thread, it seems some have missed the point.

It is NOT the studs, gaskets, head machining, or anything else that is the problem on this motor.

It IS the NUT & WASHER are TOO TALL.

At least it all worked out OK. The ARP washers are pretty thick, and the nuts have room up top for some material to be removed.

 

[stevechumo]

In my case, I didn't want to take the risk when I saw the stud that's too long or used the stud that's too short. I didn't even measure the clearance so I when ahead and used the stock bolt for that corner.

 

[Arnout]

mixing head bolts is generally speaking a bad idea

 

[stevechumo]

mixing head bolts is generally speaking a bad idea

I understand that. But well, I gotta give it a try. The engine holds up good so far at 5.5. psi after the re-torque.

 

[1UZ-HZ]

Hey, I have to say that I had the same problem (90 model 1uz), it seemed though that the whole stud was too long...after cracking an inlet cam I found it also ruined the stud, it wasn't the nut or washer. I raised this issue a couple of years ago when the first lot of ARP studs became available