Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Forums > 1- Porsche Technical Forums > 911 Engine Rebuilding Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered User
 
Join Date: Jul 2003
Posts: 715
Even for a new case, should case savers be installed?

Should case savers be installed in a brand new mg case? I will be getting a set of 930 dilavar studs (930.101.170.02), and Nikasil p+cs.

Look forward to your inputs!

Last edited by blue72s; 01-13-2005 at 10:58 AM..
Old 01-13-2005, 10:38 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered User
 
jmshepard's Avatar
 
Join Date: Oct 2004
Location: NC
Posts: 763
Both Wayne and Bruce Anderson recommend against the Dilavar solution for head studs. Is there a reason that you are planning to use them instead of Raceware?
Wayne's book strongly recommends using the Case-savers in the magnesium case.
Old 01-13-2005, 04:29 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered User
 
Jeff Alton's Avatar
 
Join Date: Jan 2003
Location: Langley,B.C.
Posts: 10,106
Use regular steel before you use Dilavar. There are lots of head stud options out there, dilivar should not be one of them.

Jeff
__________________
Turn3 Autosport- Full Service and Race Prep
jeff@turn3autosport.com
997 S 4.0, Cayman S 3.8, Boxster 2.7, Boxster S race car, 996, 955 Cayenne TT, 958 Cayenne TT
Old 01-13-2005, 04:36 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Warren Hall Student
 
Bobboloo's Avatar
 
Join Date: Aug 2000
Location: Los Angeles Ca.USA
Posts: 3,959
Garage
Oh my god! Pandoras' box has been opened again!

I guess it's to late to call Porsche and tell them not to use Dilivar in all the air cooled motors they built up through the end of production in 97'.

I myself wouldn't build a mag case motor, that uses alloy cylinders, with the regular steel studs but that's just me. I'd go with 993 studs (Dilivar). I think the raceware studs are great but really pricey. I believe they are an alloy similar to dilivar as well but have the nitrogen baked out of them to prevent cracks from nitrogen imbrittlement.

Tough call on the casesavers. They can't hurt and if you should sell down the road they should pay for themselves in the resale value of the motor.
__________________
Bobby

Warren Hall 1950 - 2008
_____"Early_S_Man"_____
Old 01-13-2005, 07:22 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Registered User
 
Jeff Alton's Avatar
 
Join Date: Jan 2003
Location: Langley,B.C.
Posts: 10,106
Sorry, I should have said the Dilivar studs used up to 89 are probably not a good choice. The 993 ones are a different story, I would not hesitate to use them.

Jeff
__________________
Turn3 Autosport- Full Service and Race Prep
jeff@turn3autosport.com
997 S 4.0, Cayman S 3.8, Boxster 2.7, Boxster S race car, 996, 955 Cayenne TT, 958 Cayenne TT
Old 01-13-2005, 07:59 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
Super Moderator
 
cstreit's Avatar
 
Join Date: Feb 2000
Location: Naperville, IL USA
Posts: 12,984
Garage
The 993 studs are mostly steel I thought, indicated as a good option by Porsche Motorsports.

I have been using them in the race motors for a while, work great!
__________________
Chris
----------------------------------------------
2001 GT3 Cup - "Pepin"
1996 993 RS Replica
2008 Yamaha R6
1971 Norton 750 Commando
Old 01-13-2005, 09:10 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #6 (permalink)
 
Registered User
 
Join Date: Jul 2003
Posts: 715
Quote:
I myself wouldn't build a mag case motor, that uses alloy cylinders, with the regular steel studs but that's just me.
My theory too.

Secondly, I think it's better to have a broken stud than a pulled stud.






Quote:
I'd go with 993 studs (Dilivar).
I thought 993 dilavars were fully threaded whereas 930's are smooth shank? Dilvar or Dilivar, whatever it's called.

Last edited by blue72s; 01-14-2005 at 02:57 AM..
Old 01-14-2005, 02:12 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #7 (permalink)
Banned from Pelican
 
snowman's Avatar
 
Join Date: Feb 2003
Location: So California
Posts: 3,787
I am confused by the chart. you show a larger coef of expansion and yet a lower change in length for the cylinders than the studs.
Old 01-14-2005, 05:07 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #8 (permalink)
Author of "101 Projects"
 
Wayne 962's Avatar
The 993 studs generally do not have the problems that the early ones had.

As for your question on case savers, if it was my case, I would do it. It also depends upon the engine too. A 2.0L 911T engine almost never pulled studs because it wasn't exposed to extreme thermal stresses like the California 2.7 engines. If you're building a performance motor then definitely install the case savers. If you're building a T motor, then you can probably get away without it.

-Wayne
__________________
Wayne R. Dempsey, Founder, Pelican Parts Inc., and Author of:
101 Projects for Your BMW 3-Series 101 Projects for Your Porsche 911 How to Rebuild & Modify Porsche 911 Engines 101 Projects for Your Porsche Boxster & Cayman 101 Projects for Your Porsche 996 / 997
Coming Soon:
SPEED READ: Porsche 911 (October 2018)
Old 01-14-2005, 09:37 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #9 (permalink)
Registered User
 
Join Date: Aug 2003
Location: New Zealand
Posts: 310
Jack

Not ofter
Old 01-15-2005, 01:43 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #10 (permalink)
Registered User
 
Join Date: Aug 2003
Location: New Zealand
Posts: 310
Jack

Quote:
I am confused by the chart. you show a larger coef of expansion and yet a lower change in length for the cylinders than the studs.
Not often you miss the obvious :-) , The studs are significantly longer than the cylinders, Also I'm not sure how relevant this is because I doubt the studs operate at the same temp as the cylinders

Neven
Old 01-15-2005, 01:45 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #11 (permalink)
Banned from Pelican
 
snowman's Avatar
 
Join Date: Feb 2003
Location: So California
Posts: 3,787
Yeh, I see, big difference in length. Won't ask why the big difference, but the stud sticks thru the head, the head expansion also matters in the overall equation. As to temp differance, it is measureable and probably relatively small at operating temp, but durning warm up could be extreem. In any case steel seems to be the best pick, followed by Covar or is it Kovar?

Anyway in the real world nothings perfact, but you do the best you can.

A friend just blew up a New Cosworth engine, seems they didn't warm it up completely and the hour glass shaped cylinders might have worked against them because of it. They figured the lack of warm up was the problem because they are running it DEtuned at 980 Hp.
Old 01-15-2005, 08:25 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #12 (permalink)
Registered User
 
Join Date: Aug 2003
Location: New Zealand
Posts: 310
Jack

Quote:
As to temp differance, it is measureable and probably relatively small at operating temp
I can't see why? There is no direct contact between the cylinders and studs (Porsche explicitly state the studs should not contact the cylinders), As the studs are heated radiantly by the cylinders and by contact at one end and they sit in airflow I'd expect them to be cooler, maybe someone could confirm this.

Neven
Old 01-15-2005, 09:57 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #13 (permalink)
Warren Hall Student
 
Bobboloo's Avatar
 
Join Date: Aug 2000
Location: Los Angeles Ca.USA
Posts: 3,959
Garage
Quote:
As the studs are heated radiantly by the cylinders and by contact at one end and they sit in airflow I'd expect them to be cooler, maybe someone could confirm this.
True. As Jack said nothings perfect, you do the best you can. I remembering seeing a picture of some studs that had fiberglass jackets to counteract the cooling effect of the air over the studs. Kind of a "pig in a blanket" if you will.
__________________
Bobby

Warren Hall 1950 - 2008
_____"Early_S_Man"_____
Old 01-15-2005, 11:02 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #14 (permalink)
Banned
 
Join Date: Jun 1999
Location: SJ
Posts: 479
Use full threaded 993 studs.,cheers Antonio.
Old 01-16-2005, 04:11 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #15 (permalink)
Reply

Thread Tools
Rate This Thread
Rate This Thread:

 


All times are GMT -8. The time now is 09:41 AM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.