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 > Porsche Forums > Porsche 911 Technical Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered User
 
Join Date: Jan 2004
Location: Birmingham Al
Posts: 390
911SC motor

I have bought a grey market 911SC and have some questions about cylinder indentification. If you look under the car at the cylinders, I can't tell how to determine if they are Nikasil or Alusil or some other type. How can I determine cylinder type and compression type of this engine? The engine has been abused but runs great and has good compression. It has 75000 miles on it. Would you recommend rebuilt or run it until it dies? Thanks. Jimmy

Old 01-28-2004, 06:02 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Senior Member
 
Superman's Avatar
 
Join Date: Mar 2000
Location: Lacey, WA. USA
Posts: 21,297
Experts can make an opinion about cylinders based on color, but there are no visible markings you can see until you remove the cylinder, or at least remove the air deflectors. SC engines have been known to go perhaps a half-million miles without rebuilding. That being said, they can usually use a valve job at 150k or so. Usually they get disassembled when one of the exhaust-side head studs break due to corrosion. If none of your studs are broken, then you have the option of just driving the thing. If it ain't broken, don't fix it.
__________________
Man of Carbon Fiber (stronger than steel)
Old 01-28-2004, 06:15 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered User
 
Join Date: Jan 2004
Location: Birmingham Al
Posts: 390
Thanks for your quick reply Superman to my question. I have some cylinders and pistons from another engine that are Mahles and they appear to have the numbering system and name cast vertically which makes this very difficult for me to tell. These cylinders look different, however. If I took the air guides off, would that tell me more? Also, how about the compression ratio? I've got another engine from a magnesium cast block with the steel studs that I was planning on using if the pistons and cylinders are acceptable. Just trying to determine what course of action to take without spending a lot of money on jugs and pistons. Thanks. Jimmy
Old 01-28-2004, 07:45 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Super Moderator
 
cstreit's Avatar
 
Join Date: Feb 2000
Location: Naperville, IL USA
Posts: 13,322
Garage
Often you can tell on the SC's by counting the find on the cylinder. I think the Mahle had one extra...

Do a search on this and I'll bet you come up with your answer.
__________________
Chris
----------------------------------------------

2001 GT3 Cup - "Pepin"
1999 Spec Miata
1996 993 RS Replica
2010 Harley 48
2013 Honda 250 CRF
1971 Norton 750 Commando
Alcon Brake Kits
Old 01-28-2004, 08:01 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Registered User
 
Join Date: Jan 2004
Location: Birmingham Al
Posts: 390
HMMMMMM,
Know a little ,but not a lot What do you mean counting the find
Old 01-28-2004, 08:04 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
What?!?!
 
DonDavis's Avatar
 
Join Date: Mar 2002
Location: Mesa, Az
Posts: 3,495
Garage
I bet he meant "fin".
__________________
running shoes, couple tools, fishing pole
1996 Subaru Legacy Outback AWD, 5speed
1964 Land Rover SII A 109
Old 01-28-2004, 08:07 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #6 (permalink)
 
Registered User
 
Join Date: Jan 2004
Location: Birmingham Al
Posts: 390
Old 01-28-2004, 08:10 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #7 (permalink)
Registered User
Counting the fins. This has been discussed several times before. I don't recall the fin count being absolute though. Perhaps I'm wrong. As Cris suggested a search will expand upon this.
__________________
Warren & Ron, may you rest in Peace.
Old 01-28-2004, 08:11 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #8 (permalink)
Registered User
 
Join Date: Jan 2004
Location: Birmingham Al
Posts: 390
Being in rookie status need little more help on what you are calling a search. dont remember factory manual telling this

Last edited by jjemg; 01-28-2004 at 08:39 AM..
Old 01-28-2004, 08:17 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #9 (permalink)
Registered User
 
ChrisBennet's Avatar
 
Join Date: Aug 2001
Location: Nashua, NH USA
Posts: 8,092
Quote:
Originally posted by jjemg
Being in rookie status need little more help on what you are calling a search. dont remember factory manual telling this
They are talking about Pelican's search capability. It's the button near the upper right corner.
__________________
'80 911 Nogaro blue Phoenix!
'07 BMW 328i Coupe
http://members.rennlist.org/messinwith911s/
Old 01-28-2004, 09:05 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #10 (permalink)
Senior Member
 
Superman's Avatar
 
Join Date: Mar 2000
Location: Lacey, WA. USA
Posts: 21,297
I think the Alusils are a little more silvery than the Mahles. There is a thread on the Engine Rebuild forum that is fascinating to engineers, and engineer wanabees like myself, regarding the method for treating Alusils so they can be reused. I reused mine with good results. Some might assert that Alusils are superior in some ways to Mahle. I hope this starts a fight. I love fights. The greatest wear JW could find on any of my cylinders was .0015". This was at 182K miles!!!!!!

So, I'm going to reiterate my previous advice. If it ain't broken, don't fix it. If you head studs are in one piece, and if your compression and leakdown numbers are good, I'd strongly suggest you button her up and drive with confidence. Unless you're itchin' to spend a bunch of money or install HI PO parts, or both. Even without P&Cs, once the engine is apart you'll succumb to the "while I'm in there" sickness. It'll cost a couple of grand anyway. Unless you replacing nothing but gaskets. And I would not disassemble a motor for that.

Your '83 Engine has 9.3:1 pistons. Porsche did a good job designing this engine. Improvements are both difficult and expensive.
__________________
Man of Carbon Fiber (stronger than steel)
Old 01-28-2004, 09:35 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #11 (permalink)
drag racing the short bus
 
dd74's Avatar
 
Join Date: May 2002
Location: Location, Location...
Posts: 21,980
Jim - you are truly the voice of wisdom.

jjemg - run it until it dies, which it may never do. This has been the advice handed down to me by almost every Porsche shop I've called. Feel lucky you don't have to spend the $5 or $6,000 that a rebuild might cost.

If you really want to test any doubts you might have about your engine, I suggest taking it to the track. If it doesn't break there, I think all is good everywhere else.

__________________
The Terror of Tiny Town
Old 01-28-2004, 09:43 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #12 (permalink)
Reply

Thread Tools
Rate This Thread
Rate This Thread:

 


All times are GMT -8. The time now is 05:45 AM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2020 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.