300ZX Turbo to Downpipe Bolts - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Engine Performance This section is for discussion on all engine building related questions.
Sponsored by:
Sponsored by:

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 10-13-2012, 02:37 PM   #1
Elite Member
Thread Starter
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,008
Total Cats: 583
Default 300ZX Turbo to Downpipe Bolts

I've recently torn down my install after about a year and a half and 15000 miles of driving. A head gasket with 200K miles on it was the catalyst.

In addition to the head gasket, it became obvious that I need to change my hot-side connectors. The mild steel bolts that I had used for manifold to turbo were completely inadequate. On had sheared in use. The other three had bad cases of thermal creep (turbo was loose) and sheared during removal. Only the safety wiring was keeping things together. TSE's M10 x 1.5 Inconel studs are now going in to take care of this area.

I used similar safety-wired mild steel bolts for the turbo to downpipe connection. These held up, were tight and came out undamaged, although the zinc corrosion coating was long gone. They see a lot less heat than the manifold to turbo area. Nevertheless, I'd like to upgrade these as well and have been looking around for suitable bolts. During my internet searching, I came across the factory early-90s Nissan 300ZX turbo to downpipe bolts. Supposedly, these were Inconel. Does anyone know anything about these particular bolts? Material (for certain)? M8, M10, other? Thread pitch? I can't seem to find these details anywhere.

Thanks in advance guys. If these really are Inconel M8 x 1.25 for $5 each, it would seem like a sweet solution.
hornetball is offline   Reply With Quote
Old 10-13-2012, 02:46 PM   #2
NB/VVT Connoisseur
iTrader: (23)
 
viperormiata's Avatar
 
Join Date: Aug 2008
Location: Key West
Posts: 6,065
Total Cats: 253
Default

I remember reading that Nissan used inconel bolts/studs on the Skylines and perhaps a few other cars. I'm sure they won't be M10, but a street car should get along just fine with inconel M8's.
viperormiata is offline   Reply With Quote
Old 10-18-2012, 04:20 PM   #3
Elite Member
Thread Starter
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,008
Total Cats: 583
Default Bolts Came In

So, I ordered the bolts (1990-1996 Nissan 300zx OEM Turbo to Downpipe Bolt).

$3.50 each!

The picture shows what I got. M8x1.25x28mm. Inconel. Nissan OEM. I think these are going to work really well. Happy with the purchase.

Easily drilled for safety wire, so long as your drill bit is sharp. The bolts do dull the bit quickly. Once it starts chipping rather than cutting, toss the bit. I've been using about 1.5 bits per bolt (I ordered 8 bolts).

Wouldn't use these on the manifold to turbo connection -- you want studs there for disassembly (got TSE's kit). But these should be just the ticket for the turbo to downpipe.
Attached Thumbnails
300ZX Turbo to Downpipe Bolts-granbury-east-20121018-00111.jpg  
hornetball is offline   Reply With Quote
Old 08-22-2014, 04:16 PM   #4
Senior Member
 
Join Date: Apr 2011
Location: Martin, Slovakia
Posts: 513
Total Cats: 71
Default

Bump

Great information Rick. +

Encouraged by your success I went to my local Nissan dealer and ordered some 300zx studs. It seems in addition to the bolt you ordered there are 2 additional types of inconel studs used on the 300ZX turbo setups.



1406440P01 is around 31 mm long and is the one used on the t2 flange. 1441417F00 is around 35mm long and is the one used on the downpipe flange. As far as I know they are inconel as
1) The Nissan man said the are
2) They are non magnetic


Originally the t2 side nuts look like they were locked in position with lock tabs. This shows the 1406440P01 part mounted on a t28 manifold.



I will test these and update with the results.
Attached Thumbnails
300ZX Turbo to Downpipe Bolts-turbostuds300zx_zps7642b8ba.png   300ZX Turbo to Downpipe Bolts-p1060319_zpsc30e7117.jpg   300ZX Turbo to Downpipe Bolts-p1060316_zps58e53bd2.jpg  
sturovo is offline   Reply With Quote
Old 08-22-2014, 04:26 PM   #5
Elite Member
Thread Starter
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,008
Total Cats: 583
Default

I should add that long-term, I've had good service from the Nissan turbo-to-downpipe bolts. I've disassembled/reassembled easily a couple of times over the last two years and been able to reuse the hardware with no issues.
hornetball is offline   Reply With Quote
Old 08-22-2014, 04:28 PM   #6
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,163
Total Cats: 2,573
Default

If anyone is looking for alternatives, I used Mazda rx7 FD bolts, which are also m10 and also inconel, and also work great.
18psi is offline   Reply With Quote
Old 08-22-2014, 04:28 PM   #7
Elite Member
iTrader: (3)
 
concealer404's Avatar
 
Join Date: Aug 2011
Posts: 8,460
Total Cats: 781
Default

This stuff should be bueno for any 2554/2560/2860, etc?
concealer404 is offline   Reply With Quote
Old 08-22-2014, 06:42 PM   #8
SadFab CEO
iTrader: (3)
 
hi_im_sean's Avatar
 
Join Date: Sep 2012
Location: your mom's house phoenix, AZ
Posts: 3,901
Total Cats: 602
Default

thanks for the long term report. i am in the middle of trying to find cheaper alternatives to TSE, and finally just broke down and bought some inconel bar and im having it machined by a friend. i may still get some of these for the DP though
hi_im_sean is offline   Reply With Quote
Old 08-23-2014, 02:26 AM   #9
Junior Member
iTrader: (5)
 
Join Date: Oct 2011
Location: San Diego, CA
Posts: 402
Total Cats: 21
Default

I also used a set of the Nissan ones for my turbine housing to exhaust manifold on my MSM and they haven't budged within almost 2 years. I was able to spare at least 4 of the original nuts that were on the MSM turbine/DP setup and used them with these studs.
slmhofy is offline   Reply With Quote
Old 08-24-2014, 06:21 PM   #10
Senior Member
 
Join Date: Apr 2011
Location: Martin, Slovakia
Posts: 513
Total Cats: 71
Default

Quote:
Originally Posted by 18psi View Post
If anyone is looking for alternatives, I used Mazda rx7 FD bolts, which are also m10 and also inconel, and also work great.
Good information Vlad. I guess the part no for these Mazda studs is 9YA9-21-003? They look like they are regular M10 x 1.5 mm thread pitch.
95 Rx7 Large Exhaust Manifold to Turbo Stud...


If M10 x 1.25mm pitch is needed then Subaru 800910340 are an option.
Attached Thumbnails
300ZX Turbo to Downpipe Bolts-kgrhqvl0e9kchgvsbplsloslg60_12_zps9ebb1fe3.jpg  
sturovo is offline   Reply With Quote
Old 08-24-2014, 07:00 PM   #11
Junior Member
iTrader: (6)
 
Join Date: Feb 2011
Posts: 420
Total Cats: 8
Default

We used the 300zx studs and stage8's on billybobsters turbo to downpipe and a TSE manifold to turbo kit. Its been 2 seasons now? they are holding perfectly. also bracing the downpipe probably helped a ton.
Twibs415 is offline   Reply With Quote
Old 08-24-2014, 07:32 PM   #12
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,163
Total Cats: 2,573
Default

Quote:
Originally Posted by sturovo View Post
Good information Vlad. I guess the part no for these Mazda studs is 9YA9-21-003? They look like they are regular M10 x 1.5 mm thread pitch.
95 Rx7 Large Exhaust Manifold to Turbo Stud...


If M10 x 1.25mm pitch is needed then Subaru 800910340 are an option.
Yep, thanks for the part#. I always forget to look that up. Depending on which turbo you use you sometimes gotta trim them - they're about 10mm too long.
And yes on the subaru studs too - I've actually used those too with no issues before. Though I'm not sure those are inconel - at least I never noticed that word in any of the part names or descriptions.
18psi is offline   Reply With Quote
Old 08-24-2014, 09:09 PM   #13
Moderator
iTrader: (11)
 
sixshooter's Avatar
 
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 15,630
Total Cats: 1,559
Default

I was using the Inconel M10 stud kits from Full Race as a less expensive alternative to TSE, fwiw.
sixshooter is online now   Reply With Quote
Old 08-24-2014, 10:23 PM   #14
Elite Member
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,091
Total Cats: 90
Default

Yep, 300ZX turbo to manifold studs here. Holding up well. I need to remember to recheck my nuts again and see if the copper ones backed off. If they did it will be time to order the M8 stage 8 fastener kit on amazon for cheap.
Leafy is offline   Reply With Quote
Old 08-25-2014, 01:35 PM   #15
Junior Member
iTrader: (5)
 
Join Date: Oct 2011
Location: San Diego, CA
Posts: 402
Total Cats: 21
Default

Also, these may work for an M10 option. One of the other RX-7 studs.

9YA9-01-002
slmhofy is offline   Reply With Quote
Old 10-27-2014, 12:19 PM   #16
Junior Member
 
Join Date: May 2008
Location: Grants Pass, OR.
Posts: 449
Total Cats: 14
Default

Leafy Make sure the kit has steel tear drop tabs, I ordered a Stage 8 kit from Summitt that turns out had aluminum tabs and liquidfied 2 of them.
jmann is offline   Reply With Quote
Old 10-27-2014, 12:22 PM   #17
Elite Member
iTrader: (1)
 
Leafy's Avatar
 
Join Date: Jun 2012
Location: NH
Posts: 9,091
Total Cats: 90
Default

Cripe. I havent had the nuts loosen up this time. I put extra effort into making sure the two hard to tighten nuts were tight and they didnt loosen up this time.
Leafy is offline   Reply With Quote
Old 10-28-2014, 05:55 AM   #18
Junior Member
 
Join Date: Aug 2010
Posts: 81
Total Cats: -9
Default

Quote:
Originally Posted by viperormiata View Post
I remember reading that Nissan used inconel bolts/studs on the Skylines and perhaps a few other cars. I'm sure they won't be M10, but a street car should get along just fine with inconel M8's.
No OEM uses Inconel. It is way too expensive for production vehicles.

Inconel looks similar to stainless steel. These studs are 12.9 heat treated steel.
Lloyd_D is offline   Reply With Quote
Old 10-28-2014, 08:07 AM   #19
Newb
iTrader: (1)
 
Join Date: Feb 2014
Location: Palm Harbor FL
Posts: 16
Total Cats: -2
Default

^incorrect, lots of nissan cars have used inconel, as stated lots of OEM turbocharged aplications, particularly those using small turbine housings relative to displacement used inconel fasteners. If they didint there would be lots of factory failures.
MrSauce is offline   Reply With Quote
Old 10-28-2014, 08:52 AM   #20
Moderator
iTrader: (11)
 
sixshooter's Avatar
 
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 15,630
Total Cats: 1,559
Default

12.9 steel is very brittle and would do very poorly in a high temperature, heat-cycled application. It also has a very different coefficient of expansion than the cast steel it is being used to retain. See the 70 page thread where this has been beaten to death for years on this forum. Inconel is the droid you are looking for.
sixshooter is online now   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Another Cast Manifold Corky Bell Prefabbed Turbo Kits 18 11-22-2016 10:01 PM
Back to Stock Part Out!! Turbo Parts, MS2 Enhanced 01-05, Suspension, and MOAR! StratoBlue1109 Miata parts for sale/trade 16 10-02-2015 10:39 AM
Low oil pressure after 1.8 swap and new turbo setup JesseTheNoob DIY Turbo Discussion 15 09-30-2015 03:44 PM
1996 Turbo Build Goldwar DIY Turbo Discussion 2 09-29-2015 10:20 AM


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 10:34 PM.