Recommendations on manifold?

Discussion in 'Non Technical' started by SuperZ, Jul 2, 2015.

  1. SuperZ

    SuperZ Resident Z lunatic


    I know a few manifolds changed design recently, what's the latest on recommendations from the forum? (saw a comparison a while ago before the changes)

    I have 5 Bolt Z dumps 3inch and GT2860RS / 800cc sard twins/ nistune /ARP etc

    Planning 500-600HP (I know stockies can do it, but clearly there are benefits o some of the aftermarket ones)

    What's a good manifold to run with?



  2. SuperZ

    SuperZ Resident Z lunatic

    I found the answer!


  3. SrAfciGeR

    SrAfciGeR Member

    I went with Stainless Steel Design.


    Size of GT2871R required some extra space and the fact SS don't have that extra bent on the pipe like cast ones do...
    That pretty much made my decision to go with the SS...
  4. SrAfciGeR

    SrAfciGeR Member

    However if you go with those you will need to cut the slot for oil measurement stick, as the Chinese manufacturer didn't think about that...
    As well I deleted the EGR by welding the washer over EGR outlet ...
  5. rob260

    rob260 Administrator Staff Member

    They'll be fun to pull out when they crack...,
  6. rob260

    rob260 Administrator Staff Member

    Mike Smith Performance
  7. SrAfciGeR

    SrAfciGeR Member

    You need to wrap them so they won't
  8. bRACKET

    bRACKET Do Right Dean

    They don't crack because they aren't wrapped, they crack because the weight of the turbo, coupled with the heat and engine/drivetrain vibrations crack the welds.

    I would never run a stainless exhaust manifold. Steam pipe if available, or cast in a situation like ours where removing a manifold/turbo is an engine out job.
  9. SrAfciGeR

    SrAfciGeR Member

    Well big factor is temperature and expansion contraction on the joints/welds ... when wrapped welds do have time to contract on slower paste so "crack the welds" doesn't occur...

    I very well know about weight of the turbo and my setup is supported thus 90% crack factor is eliminated.

    However cast iron also creaks... Maybe not as much as tubular still but it does!

    If there are Mid still manifolds available of the shelf I would be going with them... But there are not!
    My welding skills aren't that bad but I wouldn't go and make my own manifolds...

    No 1 choice would be Cast Stainless Still but no one makes it! And 99% chance that never will - for our cars at least !!!

    So there you go ... wave your options and go for the one you think will do the job for you.
  10. Anti

    Anti 14.7 x 14.7 = 44.1

    You can get stainless steampipe. That's what my manifolds are made of. Thick wall
  11. Jinxed

    Jinxed Moderator

    if its the weight and vibration that cacks them, could they be braced or supported (like a engine mount style) to stop them cracking
  12. rob260

    rob260 Administrator Staff Member

    Stainless manifolds are nothing new -Pentroof, Greddy, SpecialtyZ have all made and subsequently discontinued them. Those stainless manifolds you pictured ship from China @ $90/set, I wouldn't peg too many expectations on them "breaking the mould" (excuse the pun).

    I'd love to see pics of how you've braced the turbos in the Z32 such as to take the weight off the manifolds?

    If you haven't assembled the motor yet I'd strongly suggest looking at MSP cast manifolds. They support plenty of power, fit perfectly, and will never break. Sometimes spending more up front is spending less in the long run.
    Last edited: Jul 4, 2015
  13. Madcow

    Madcow Active Member

    MSP manifolds also use the oem heat sheild if slighly trimmed. This is what you want on a 300zx.

    Heatwrap will eventually fall apart. I would not like to rewrap a manifold while it is still on the car.
  14. SuperZ

    SuperZ Resident Z lunatic

    Yep - it seems AMS or MSP are the only real choices from what I have read so far.

    SS tube types can hold up to the heat /vibration and cracking only if the welds are consistent - that's the problem though - how do you know its consistent even with a top class welder? - it has to be X ray tested and given nearly all of them are not - its a simple choice to go cast (for me anyway)

    MSP claims their new upgraded manifold does have a flow equal or better to the tubular types.

    From memory the comparison between AMS and MSP was negligible but the price was not ! (comparison was the older MSP version - the AMS is 40% cheaper)

    Is it justifiable to pay for the MSP's over the AMS versions ? (noting the new MSP has extra flow)

    Or have AMS had issues with their manifolds?


  15. SuperZ

    SuperZ Resident Z lunatic

    There re a multitude of welds available to do the job quite well - the problem is the consistency of the welds regardless of type.

    Supporting the weight of the turbo can help reduce cracking from the weight only if they don't induce more vibration. Weight is only part of the equation

    Gaskets dampen vibration and if used on all points would help massively however ultimately - if the weld is weak or thin in any one SS section, once the temps go right up and this weak section becomes heated, it can blow a small hole and start a minute crack and once that happens, the cracking will continue it until it shears off.

    XRAY testing is the only way to be sure that the weld is consistent in thickness even with the best top class welders because they cannot look through welds to see the pockets or bubbles that may have even formed inside the welds even with gas or gas-less welding!

    Hope that explains the issue


    P.S. The issue for me is 5%-10% more performance from the manifold for 40% more in price - is it justified?? (MSP vs AMS cast manifolds)
  16. andy

    andy Member

    AMS have had serious quality control issues in the past with their exhaust manifolds.

    In my opinion you can either have a roll of the dice with the AMS copy or you can buy MSP and support the the innovator.
  17. ProckyZ89

    ProckyZ89 Senior Member

    Quality control issues?
    The cars I know with them have no issues apart from varying exhaust angles by a marginal discrepancy car to car sometimes causing interference on the rails of steering rod (easy to overcome)

    AMS or MSP easily (ash manifolds don't bother with.. I'll explain if needed)

    And steel manifolds? Well there's a reason no high hp zeds use them at all or reliable supplier stocks them.
    Other points are all covered :)

    And yes
    OEM heat shields can be used on AMS or MSP with manipulation :)

    Also to start a fight haha
    Didn't AMS self propaganda state that AMS manifolds flowed more than MSP ;)
  18. SuperZ

    SuperZ Resident Z lunatic

    Is that why MSP have since upgraded their manifold with a newer higher flow rate? :rofl:

    Typical isn't it :rolleyes:

    Leaning towards the AMS only because the flow rates of both are not a bottleneck at my intended HP max (less than 700 HP) I mean its only 5-10% less flow rate at max but 40% cheaper than the MSP

    Does that make sense to any others or have I missed something else?

    (or unless others have had other quality issues with AMS that is?)

    Apparently all casts have variance issues by some degrees and this is not typical of just AMS manifolds but all of them

    MSP are made in the GARRETT foundries in the USA and that means quality casting (less variation) whereas AMS are china foundries and the composition is not made public ! (the concerning part is always the gambling part and the word china is scary when it comes to quality)


    P.S. They are probably so close because its alleged that AMS copied the MSP manifold :rofl: They even started a website specifically about this (won't allow me to type it in here I think because it has a pirate word in it!LOL)
    Last edited: Jul 4, 2015
  19. andy

    andy Member

    This is one example where three sets of AMS manifolds had the turbo studs out of alignment so the turbo could not be fitted or the exhaust port out of alignment with the studs or both.

    They may have improved quality control since or maybe not. If you buy though someone like Z1 that can check the manifolds before shipping to Australia then you should be ok. If they are drop shipped directly from a manufacturer in China then you will be rolling the dice.

    There was some flow testing discussion on

    The bitterness of poor quality remains long after the sweetness of low price is forgotten.
    Last edited: Jul 4, 2015
  20. SuperZ

    SuperZ Resident Z lunatic

    Cheers Andy

    Seems to be a sh...storm in teacup right there!
    Thought the dust had settled by now - but both have been "upgraded" since creating a whole new world of confusion

    There is now websites dedicated to this sh..storm!

    USA vs CHINA (are superpowers behind this - LOL)

    I note MSP and AMS both claim new higher figures with their new versions :rolleyes:

    The issue is not flow rates with me as stated earlier as the HP I am after (500-600HP), can even be achieved with stocks and a little work. My concern is the bolt / mounting issues but it neither has AMS stamped on them nor does it appear to be the upgraded version - so the evidence is still not there for me.

    There is too much propaganda involved in the sh..storm to really know what's going on anywhere really.:rofl: :(

    When too many people who know a lot about Z's are arguing with each other, its generally fairly close and its hard to believe anyone - lol

    I have seen both types yield high HP!

    So I have been speaking to Coz and am now waiting for him to tell me if the AMS will have any issues with mounting etc. I trust Coz to decide the fate of my car given his knowledge and ability to measure on site as well as the feedback he obtains - he has never let me down before.

    Cannot wait for Coz's response - he sells both and has for a while!

    Appreciate the help everyone ! :zlove::zlove::zlove:


Share This Page