Intake Manifold Studs - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Race Prep Miata race-only chat.
Sponsored by:
Sponsored by:

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 12-02-2013, 12:09 PM   #1
Elite Member
Thread Starter
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,091
Total Cats: 90
Default Intake Manifold Studs

I was finally bitten. When pulling my intake manifold off one nut just fell off with the half stud in it. What are you track people doing for intake manifold studs? They seem to fail left and right for the auto-x people, the csp car ended up replacing an entire set worth this season IIRC. They're m8x1.25 I need to pull a good one to get the length. Do we just replace with OEM as the break or have an upgraded option? Mcmaster doesnt have 10.9 studs, but they do have 4140 for pressure bolted connections in high pressure systems. Minimum tensile strength of 124,000 psi and max hardness of Rockwell C35, which is in between class 8.8 and class 10.9 for both strength and hardness.
Leafy is offline   Reply With Quote
Old 12-02-2013, 01:03 PM   #2
Elite Member
iTrader: (5)
 
Join Date: Dec 2010
Location: Raleigh, NC
Posts: 1,970
Total Cats: 49
Default

I haven't had any issues with mine. Are you maybe overtorquing them? I remember them having a pretty low torque range.
Seefo is offline   Reply With Quote
Old 12-02-2013, 01:07 PM   #3
Elite Member
Thread Starter
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,091
Total Cats: 90
Default

I tightened them with a 1/4" drive ratchet so I doubt I yielded it. The failure looks like fatigue, it didn't look over torqued.
Leafy is offline   Reply With Quote
Old 12-02-2013, 02:42 PM   #4
Senior Member
iTrader: (10)
 
Join Date: Aug 2007
Location: Fredericton, NB
Posts: 1,187
Total Cats: 4
Default

...maybe the intake manifold brace serves a purpose after all...
Preluding is offline   Reply With Quote
Old 12-02-2013, 08:39 PM   #5
Senior Member
 
Join Date: Dec 2010
Location: Auckland, NZ
Posts: 782
Total Cats: 23
Default

I have been racing mine for the past year and previous owner for 4 years with out any problem..

This is WITH the brace...1600cc motor, though I doubt that makes a difference....

Now the exhaust manifold, thats a different story!
mx5-kiwi is offline   Reply With Quote
Old 12-02-2013, 08:45 PM   #6
Elite Member
Thread Starter
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,091
Total Cats: 90
Default

Yeah, I've been looking some more and it looks like this is just an issue that us cone dodging, weight weenies that rev the car to the moon and back have to deal with.
Leafy is offline   Reply With Quote
Old 12-02-2013, 09:02 PM   #7
Elite Member
 
codrus's Avatar
 
Join Date: Mar 2007
Location: Santa Clara, CA
Posts: 3,877
Total Cats: 344
Default

Quote:
Originally Posted by Leafy View Post
rev the car to the moon and back have to deal with.
I suspect the revving is the culprit.

I've done about a hundred autoxes on mine, with nary an intake manifold stud problem so far, but I don't rev it above the stock 7200 (here's little point with a a 2560).

--Ian
codrus is online now   Reply With Quote
Old 12-03-2013, 10:44 AM   #8
Junior Member
iTrader: (1)
 
Join Date: Aug 2008
Location: Austin, TX
Posts: 239
Total Cats: 4
Default

So bust out the sawsall, grinder and other associated metal removal tools and make the intake lighter! Less mass means less torque on those studs.
mcfandango is offline   Reply With Quote
Old 12-03-2013, 10:48 AM   #9
Elite Member
Thread Starter
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,091
Total Cats: 90
Default

Quote:
Originally Posted by mcfandango View Post
So bust out the sawsall, grinder and other associated metal removal tools and make the intake lighter! Less mass means less torque on those studs.
The thing is freaking heavy, its also borrowed.
Leafy is offline   Reply With Quote
Old 12-03-2013, 10:49 AM   #10
Elite Member
iTrader: (8)
 
Join Date: Dec 2008
Location: Kingston, Ontario
Posts: 2,791
Total Cats: 71
Default

tap the bolts out for a larger size- best option, not easy to do properly in the car.
use higher grade bolts (not as ductile though in most cases, so it likely wont help)
use the intake manifold bracket - if your a weight weenie for the 1/2 lb that the brace isare, drill some holes in it in the middle of the web, leave the outside of the web for strength.
shlammed is offline   Reply With Quote
Old 12-03-2013, 01:38 PM   #11
Junior Member
iTrader: (1)
 
Join Date: Aug 2008
Location: Austin, TX
Posts: 239
Total Cats: 4
Default

Then I'd vote for bracing. Just like on the turbo/exhaust side of things. I actually had my turbo come off the manifold recently because of a broken exhaust hanger in the rear.

Sucks to add weight but it might be necessary. Also you can probably fab up something lighter and just as good than the factory brace with a swaged rod or turnbuckle.
mcfandango is offline   Reply With Quote
Old 12-03-2013, 02:14 PM   #12
Elite Member
Thread Starter
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,091
Total Cats: 90
Default

But the turn buckle wont work, too many axis of movement, it just becomes a point for the manifold to rotate around. It needs a solid connection if its going to have a brace.

I took a look back at one of the old engineering texts, my failure may potentially be an under torqued fastener, or just a lack of yield strength in the fastener. I'm going to find some class 10.9 studs, and actually use a torque wrench. And probably re-calculate the actual torque spec to be 60% of yield for the new studs.
Leafy is offline   Reply With Quote
Old 12-03-2013, 02:40 PM   #13
Junior Member
iTrader: (1)
 
Join Date: Aug 2008
Location: Austin, TX
Posts: 239
Total Cats: 4
Default

If you are recreating the factory type brace, I don't see how a turn buckle would have too much motion. Lock the buckle into the length you want. I'm not saying put rod ends on it.
mcfandango is offline   Reply With Quote
Old 12-03-2013, 02:46 PM   #14
Elite Member
Thread Starter
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,091
Total Cats: 90
Default

Quote:
Originally Posted by mcfandango View Post
If you are recreating the factory type brace, I don't see how a turn buckle would have too much motion. Lock the buckle into the length you want. I'm not saying put rod ends on it.
That seems more expensive than just drilling a bunch of holes in the stock brace. Or just running stronger studs with a re-calculated torque spec.
Leafy is offline   Reply With Quote
Old 12-03-2013, 03:30 PM   #15
Elite Member
iTrader: (5)
 
Join Date: Dec 2010
Location: Raleigh, NC
Posts: 1,970
Total Cats: 49
Default

Quote:
Originally Posted by Leafy View Post
That seems more expensive than just drilling a bunch of holes in the stock brace. Or just running stronger studs with a re-calculated torque spec.
just don't bottom them out in the head, not really sure how much space is back there. that won't be fun to get out...

btw, are you running a phenolic intake manifold gasket by chance?
Seefo is offline   Reply With Quote
Old 12-03-2013, 03:31 PM   #16
Senior Member
 
Join Date: Dec 2010
Location: Auckland, NZ
Posts: 782
Total Cats: 23
Default

How much does the stock brace weigh?

and is the weight cost REALLY worth the hassle?
mx5-kiwi is offline   Reply With Quote
Old 12-03-2013, 03:34 PM   #17
Elite Member
Thread Starter
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,091
Total Cats: 90
Default

No stupid plastic gasket. I havent weight the brace and associate fasteners but it must be around 5 pounds. Its also in the way of where I want to put my power steering pump maybe.
Leafy is offline   Reply With Quote
Old 12-03-2013, 03:37 PM   #18
Junior Member
iTrader: (1)
 
Join Date: Aug 2008
Location: Austin, TX
Posts: 239
Total Cats: 4
Default

I have a piles of unused parts from all sorts of stuff. This would be nothing to scrounge up something to create it. Cost? You must not value your time very much. Taking much weight out of the factory brace is going to take a while even with a drill press.

Even cheaper? A piece of square or round tubing could be abused in pretty quick fashion for this and probably still lighter than the abused factory one.

It looks like Dorman has some M8x1.25 10.9 studs.
Dorman Products - Double-Ended Studs Class 10.9

Last edited by mcfandango; 12-03-2013 at 03:47 PM.
mcfandango is offline   Reply With Quote
Old 12-03-2013, 03:37 PM   #19
Elite Member
iTrader: (5)
 
Join Date: Dec 2010
Location: Raleigh, NC
Posts: 1,970
Total Cats: 49
Default

Quote:
Originally Posted by Leafy View Post
No stupid plastic gasket. I havent weight the brace and associate fasteners but it must be around 5 pounds. Its also in the way of where I want to put my power steering pump maybe.
5 lbs? you are crazy. that brace is no more than 1.5 lbs with the 3 bolts it needs.
Seefo is offline   Reply With Quote
Old 12-03-2013, 03:58 PM   #20
Junior Member
 
Join Date: Mar 2012
Location: Searcy, AR
Posts: 149
Total Cats: -2
Default

Solution, a lighter intake that is also *SP legal. Coming soon.

OP question, check with ARP, they make all kinds of products that don't have a specific application.
FrankL is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 57 07-19-2017 05:11 PM
Expected intake temps on the track? tazswing Race Prep 20 10-03-2015 12:04 PM
Moroso Air Oil Separator Catch Can Aroundcorner Miata parts for sale/trade 2 10-01-2015 04:20 PM
ISO 1.6 turbo cast iron manifold cale saurage DIY Turbo Discussion 16 10-01-2015 12:25 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 10:02 PM.