Thread: Ceramic coated TD5 exhaust manifold

Originally Posted by Catmatt

High EGTs usually from a 'chipped'or remapped ECU combined with a manifold that hasn't had the webs 'eased' like the pic from the 1st post.

If you haven't destressed the manifold, they tend to warp and pull a exhaust stud....first indication is the classic 'whistle' from the exhaust when accelerating - especially when cold and telltale exhaust soot around the warped area.

Not a big deal to fix and when you get the manifold back after getting it surface milled flat, remove the webbing between the ports and if you are really motivated, replace all of the original exhaust studs with better after-market items and you won't have any further problems

Hmmmmm! I'm chipped and fitted an EGT gauge at the same time - what is the danger zone for warping of the manifold? i don't think i've been above 550 deg C

onebob

Originally Posted by Catmatt

Not a big deal to fix and when you get the manifold back after getting it surface milled flat, remove the webbing between the ports and if you are really motivated, replace all of the original exhaust studs with better after-market items and you won't have any further problems

Actually better to remove the webbing before you get it milled.

I measured mine on a sheet of flat plate glass and it was warped 1.3mm , when I ground away the webs the warp relaxed to about .75 mm , then I machined it flat.