recently my ca18 i gained an exhaust leak with my high mount stainless manifold for a t3/t4, after going over all the gasketes thoouroughly a tech pointed out that the weld aroundthe wastegate flange looked pretty suity and should be checked…
so tonight off comes the manifold and to an exhaust shop tomorrow to get fixed up, while its off i was consedering going the extra mile and have it protected properly, ive heard some things about ceramic coating… heatwrap … what are my best options? im also going to be looking into having a flex pipe installed to relieve some weight off the manifold. Please let me know of any pointers , do’s, donts etc 
A ceramic coated / heat wrapped manifold will not stop stress cracks from an improperly braced tube manifold.
see if u can take it to a fabrication shop and see if they can weld another seam over the one that looks weak.
definitely get the flex pipe in there… i went through 2 sets of exhaust gaskets before i put in a flex piece… the exhaust should hang exactly where it attaches to the downpipe without being attached to it… ie, no weight from the exhaust should be put on the manifold… I put in a few extra spots to hang from…
… if your header is a chinese ‘Stainless steel’ header then forget repairing it and toss it out, get one made with north american made SS tubing. regardless, you’d best hope that whatever exhaust shop you took your header to has TIG welder or has the brains to change over their MIG to a SS wire and new( non mild steel contaminated ) core and shield or you’ve just wasted money and a header ( again provided it’s not a POS chinese product)…
SS has a greater rate of thermal expansion then mild steel does and ceramic cracks off of mild steel headers all the time, becuse of thermal expansion… so it makes no sense to coat a SS header with ceramic unless you enjoy wasting money and having little bits of ceramic sailing into your turbine impeller…
heat wrap or a heat shield are the options for SS parts.
well to start off i think i didnt do enough research, i picked up a kit form ss autochrome, ive heard some good some bad after the fact but figred id stick with it.
so ive already done alot of work to fit in this t3/t4 turbo, custom exhaust, oil lines, plus fmic, relocated air filter etc etc… i kinda dont wanna backtrack to far lol but i sorta am just twidling my thumbs right now as to what to do.
i have a cracked manifold with a good turbo and everythign else ready to go… can i find a quality ss manifold that will roughly fit back in without mods?
or i throw in the old low mount manifold, shell out more money and get a t28 and have everythign re-configured… again
building a new manifold that matches the existing setup is not that hard… jus comes down to money… no one can build a custom part for anywhere near the rice of the Ebay model… but then again that’s why the Ebay ones, ( when i say Ebay this also includes a whole plethora of locally sold ‘cheap headers’ ), are crap… The right materials alone are worth more then a finished ‘cheap header’ can be bought for. You also need to consider quality, design and warrenty offered when buying a custom header… Eg: I warrenty the parts I make for my customers even if someone else’s product wrecked it. But I’m also not the cheapest fabricator out there… however I’m far from the most expensive…
Take a look at what you can spend, what you plan to use it for and what matters the most in your purchase. Get references and if you can, get a look at product after a few months or even years of use…