Re: Manifold studs - Saab 9-5 Bulletin Board - Saabnet.com
The banner above is an advertisment - if it asks you to download software, please ignore.
Site News -
7/1: Members: Log In to See Fewer Ads! |
5/28: SAAB Evolutions/TSN T-Shirts $14
[General |
Members |
C900 |
9000 |
NG900 & OG93 |
93 |
95 |
NG95 |
99 |
Sonett |
Vintage Models |
Clubs |
Other Cars |
FAQs |
Gifts |
Member Photo Galleries |
Member Directory |
Classifieds |
Manuals |
*Buddy Registry |
*Mileage Registry |
Polls |
What's New |
Raffle |
Photo of the Month |
Sponsors]
[Main 95 Bulletin Board | BBFAQ |
Prev by Date | Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
Re: Manifold studs
Posted by Dean (more from Dean) on Wed, 29 Jan 2014 10:43:41
In Reply to: Re: Manifold studs, Rob Turbett, Tue, 28 Jan 2014 15:47:14
Members do not see ads below this line. - Help Keep This Site Online - Signup
I have not studied this for a while. Exhaust manifolds go through a lot of expansion cycles and this can break the studs or crack the manifold. It is not just the start-shutdown thermal cycles, but cycles that track the gas petal. The manifold flange or flange plate can be in multiple parts or saw cut in the middle to avoid some of the stresses.
If the longer studs have longer standoff ferrule , this allows for more elasticity and bending and as the manifold moves relative to the head and studs, the stresses can be reduced and the studs will be less prone to breaking. The ferrule can be shorted than optimal or not used if there are clearance problems and clearances can be a maintenance concern as well to allow access for repair and remove of other items. The or some of the holes in the manifold might appear over-sized, otherwise there is an obvious need to not "pin" the manifold to the head. If you read turbocharging books, you will see that a lot of thought can go into manifolds and what is needed for them to survive. And wisdom like never insulating exhaust manifolds. There might be some merit to insulation in some performance applications, but for a factory build daily driver, durability should be paramount.
The ferrules also move the nuts away from the heat. Without those, the nuts can scale and become reduced in size from loss of metal; try putting a wrench or socket on that.
The manifold can be moving against the manifold gasket. A cast iron manifold that is over-constrained can crack. Note that 18 ft.lb is not going to create huge clamping forces.
EPC calls the ferrules "spacers"
posted by 108.207.11...
Posts in this Thread:
Members do not see ads below this line. - Help Keep This Site Online - Signup
Post a Followup
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
StateOfNine.com
![](/tsn/xyz/stateofninebutton.gif) |
SaabClub.com
![](/tsn/xyz/scnabutton.gif) |
Jak Stoll Performance
![](/tsn/xyz/jakstollbutton.gif) |
M Car Covers
![](/tsn/xyz/mcarcoversbutton.gif) |
Ad Available
![](/tsn/xyz/buttonavailable.gif) |
![](/tsn/images/tsnmap.gif)
Random Saabnet.com Member Gallery Photos (Click Image)
This is a moderated bulletin board - Posting is a privilege, not a right.
Unsolicited commercial postings are not allowed (no spam). Please, no For Sale or Wanted postings, SERIOUSLY.
Classifieds are to be listed in The Saab Network Classifieds pages.
This is a problem solving forum for over 250,000 Saab owners, so expect to see
problems discussed here even though our cars are generally very reliable. This is not an anything goes
type of forum. Saabnet.com has been a moderated forum since 1988. For usage guidelines, see the
Saabnet.com Mission and Purpose Page. Please remember that you are
not anonymous. Site Contact | Site Donations | Other Sites by SP -
Poverty2Prosperity.org | Run Club Menlo Park | ScreenBot
Site Members do not see red text instructions, bottom of the page anchor ads, or box ads.
Click here to see all
the Site Membership Benefits!