![]() |
|
|
|
Registered
Join Date: Jan 2005
Location: los angeles
Posts: 3,087
|
Gawd - another dilivar question
Do only lower row dilivar studs break, or is it that uppers would break too, it'sjust that Porsche seldom installed them there?
I ask because I'm building a 964. It has no broken studs now. Maybe a good compromise would be to leave the upper dilivars be, and replace the lower row with 993 dilivars |
||
![]() |
|
Slippery Slope Expert
|
I wasn't aware Dilavar was ever used for the top studs but it wouldn't be the first time I was wrong!
|
||
![]() |
|
Registered
Join Date: Jun 2003
Location: Camarillo, Ca.
Posts: 2,418
|
Porsche ran full Dilivar stud on Turbo's and the 993
__________________
Aaron. ![]() Burnham Performance https://www.instagram.com/burnhamperformance/ |
||
![]() |
|
Registered
Join Date: Jan 2005
Location: los angeles
Posts: 3,087
|
As best I can tell, my '91 964 has never been apart (unless it was very expertly modified to leak addtional oil
![]() |
||
![]() |
|
Registered
Join Date: Jan 2004
Location: CT
Posts: 11,538
|
I have seen broken Dilivar studs on 964's. I would replace all the Dilivar studs.
__________________
Tom Butler 1973 RSR Clone 1970 911E 914-6 GT Recreation in Process |
||
![]() |
|
Registered
Join Date: Jan 2005
Location: los angeles
Posts: 3,087
|
Were the broken ones upper or lower row? Were the uppers dilivar?
|
||
![]() |
|
![]() |
Registered
Join Date: Oct 2008
Location: Nash County, NC.
Posts: 8,467
|
on a 964, they are all dilivar.
Bruce |
||
![]() |
|
Registered
|
My 964 engine had all steel, my friend 964rs likewise.
__________________
Magnus 911 Silver Targa -77, 3.2 -84 with custom ITBs and EFI. 911T Coupe -69, 3.6, G50, "RSR", track day. 924 -79 Rat Rod EFI/Turbo 375whp@1.85bar. 931 -79 under total restoration. |
||
![]() |
|
Registered
Join Date: Jun 2003
Location: Camarillo, Ca.
Posts: 2,418
|
If I have interpreted right, PET implies that 964 may have been all steel for the M64.01/02/03
The turbo (m64.50) had steel upper and Dilivar Lower PET has superseded all studs for the 964 to the 993 Dilivar. I seem to remember that in the introduction of the 964 they had Dilivar installed originally, but the failure rate of the stud prompted Porsche to use the Steel studs ....Anybody recall this?
__________________
Aaron. ![]() Burnham Performance https://www.instagram.com/burnhamperformance/ |
||
![]() |
|
Registered
Join Date: Jul 2000
Location: So. Calif.
Posts: 19,910
|
Dilavar is non-magnetic, but also a steel alloy.
FWIW, here's Pete Zimmerman's take on Dilavar: Cylinder Head Studs - Porsche Wiki Sherwood |
||
![]() |
|
Registered
Join Date: Jan 2005
Location: los angeles
Posts: 3,087
|
964
Introducing Senor Valdez, possibly the most interesting (if not leakiest) 964 in the world. Upper and lower studs non-magneticNo evidence this engine has ever been apart until now. ~90k miles. Note ims bearing wear, which I find to be typical. Rod and mains are in great shape. This is to those who decide to just do a top end, not knowing what lurks inside.
![]() ![]() ![]() |
||
![]() |
|