Jump to content
The mkiv Supra Owners Club

Help with stainless manifold please


Suprakeith
 Share

Recommended Posts

Hello i purchased a 2nd hand stainless exhaust manifold for my n/a and am wits ends as it blowing on cyclinder 5 below the exhaust port, i have tryed new stock gaskets,new studs and nuts and have sanded the face of manifold and head using 1200 grit wet and dry, havent rushed the job and have taken time and effort to get everything perfect, i have quite alot of experiance working on cars and the only conclusion i can come to is the manifold is warped or bent on the face going to back of engine.

If anyone has any advice please on how to stop leak as dont want to fit old manifold back on it will be very helpfull

Link to comment
Share on other sites

Hi mate my manifold was warped quite bad infact if I remember right it was 3mm out from hight to low spots.

I give mine to a friend who kindly offerd to flatten the face on it. He used a blue mask type stuff then sanded it back untill it was level.

 

So If I was you I would take a metal ruler and place the edge on the face of the manifold to see how much it is out then spray it with black paint or use graphite powder and when you start to sand you will see the high spots stright away then just work on them untill it's almost level then a thick gasket should take care of the rest ;)

Edited by FOSTA (see edit history)
Link to comment
Share on other sites

1200 grit? Jeeez, that's more suited to flatting top coat. It needs either facing up on a milling machine (hard to hold it still and at the right angle, or, if you have a steady hand and nerve, try this. Find someone with a big industrial belt sander, install 60 grit belt, and belt sand it flat. It'll probably warp again, the flange is probably one piece (very bad on a straight six), too thin (needs to be 1/2 inch really), and made of toffee in China or Korea. You can certainly get it flat again, but how long it lasts before it warps again is anyone's guess :(

Link to comment
Share on other sites

Get it to a machine shop with a horizontal milling machine and fly cut the face ;) or if its a bitch to get square a universal

milling machine with an adjustable head that you can set at the required angle.

 

Probably cost you an hours labour so around £40 - £50

 

First off though i would get a straight edge and see how far its out, granite work top

would be good if you have one :) Or a machine shop should have a surface plate.

 

If its miles out then your probably better off just fitting another better quality one

or going back to stock.

Edited by Dnk (see edit history)
Link to comment
Share on other sites

What you have to remember is every head is different, my manifold has been on 3 different engines now, 1st one it had to be cut and welded, 2nd more cutting was involved and 3rd, well lets just say its now scrap, i am thinking being rubbish quality steel that they warp over time, i am actually going to remove mine and fit a st decat with standard mani until i can get one made or Mr Whiffin makes his.

Link to comment
Share on other sites

One thing Many people forget is to use some kind of support for the manifold and the turbos its LOT of weight and its easy to wrap the tubes and even the bolts holding it to the head. Take a look at the standard setup its held down with multiple support stands.

 

Dont imo try to streight it your self take it to a machine shop

 

 

---

I am here: http://maps.google.com/maps?ll=57.729243,11.786261

Link to comment
Share on other sites

One thing Many people forget is to use some kind of support for the manifold and the turbos its LOT of weight and its easy to wrap the tubes and even the bolts holding it to the head. Take a look at the standard setup its held down with multiple support stands.

 

Dont imo try to streight it your self take it to a machine shop

 

 

---

I am here: http://maps.google.com/maps?ll=57.729243,11.786261

 

I think his turbos fell off before it left the factory mate :)

Link to comment
Share on other sites

What you have to remember is every head is different, my manifold has been on 3 different engines now, 1st one it had to be cut and welded, 2nd more cutting was involved and 3rd, well lets just say its now scrap, i am thinking being rubbish quality steel that they warp over time, i am actually going to remove mine and fit a st decat with standard mani until i can get one made or Mr Whiffin makes his.

 

I doubt very much its anything to do with the cylinder head :)

Link to comment
Share on other sites

I doubt very much its anything to do with the cylinder head :)

 

I have had 2 very slightly different heads, when i had nics manifold, it fitted on one but not the other, so either i cant replicate fitting a manifold from one head to another or they were slightly different (not massively mind but enough to mean the mani would need attention)

Link to comment
Share on other sites

I still think alot of the problem when using tubular manifolds it comes down to the lack of support. People dont put support bars and it puts alot of stress to the manifolds and bolts and yeah everything. I had a cheap tubular on my 7M and i machined the flange to get it straight. And i used 2 support stands to it aswell worked verry well.

 

 

---

I am here: http://maps.google.com/maps?ll=57.749418,11.824583

Link to comment
Share on other sites

Thank you for all the advice am going to have play again today if no joy will remove it fit standard one and check the stainless one,its a nics manifold and meant to be a good make, the flange is in two halfs each one having 3 cyclinders on. havent fitted the rest of exhaust yet so dout can be lack of support bars, i am now thinking its wrapped major as have tighten the nuts down in difference order and number 5 at the bottom is always blowing its a headache. i did buy the manifold off a bloke from the club so if i check the manifold and it is warped does anyone think will have fair case if ask for money back?

Link to comment
Share on other sites

A lot of the aftermarket 2JZ-GE manifolds on the market I see use thin section plate for the flanges which can bend from the heat of the welding. Another common problem is the 2 flanges not lining up square, they need to be fabricated on a jig so that they don't pull out of line when fabricated. Easiest fix would be to get them machined square, slotting the holes in the flanges will also help.

Link to comment
Share on other sites

Try and find someone with a machine shop are ask them to face it off (if you know anyone in that industry). Without having something to guide you, you could actually just make it worst. Would be EASY job on a mill just to go across it. Less than a 1minute job with the right equipment.

 

Otherwise Id ask the guy you bought it from to get it sorted and your take it back or you want a refund.

Link to comment
Share on other sites

Thank you for all the advice am going to have play again today if no joy will remove it fit standard one and check the stainless one,its a nics manifold and meant to be a good make, the flange is in two halfs each one having 3 cyclinders on. havent fitted the rest of exhaust yet so dout can be lack of support bars, i am now thinking its wrapped major as have tighten the nuts down in difference order and number 5 at the bottom is always blowing its a headache. i did buy the manifold off a bloke from the club so if i check the manifold and it is warped does anyone think will have fair case if ask for money back?

 

Be carefull as you are putting extra tension onto the exhaust studs and you could end up

damaging the threads in the cylinder head.

 

If i were you i'd put the stock manifold on and check the custom one how i said to earlier, it

should be pretty obvious even by just looking at it to see if its warped.

Link to comment
Share on other sites

Try and find someone with a machine shop are ask them to face it off (if you know anyone in that industry). Without having something to guide you, you could actually just make it worst. Would be EASY job on a mill just to go across it. Less than a 1minute job with the right equipment.

 

Otherwise Id ask the guy you bought it from to get it sorted and your take it back or you want a refund.

 

Less than a minute ? hmmm yeh ok, i think it would take just a bit longer to actually set it up

and get it clamped to the machine table seeing as its not exactly the easiest thing to hold.

Link to comment
Share on other sites

Less than a minute ? hmmm yeh ok, i think it would take just a bit longer to actually set it up

and get it clamped to the machine table seeing as its not exactly the easiest thing to hold.

 

Less than a minute to face it off, I didnt say less than a minute to set up, carry it into the work shop, clamp it up, clean it off, debur it, 316 would take less than a minute to face off once its set up. It will take more than that by hand, that was my meaning.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.