exhaust manifold replacement .

[RichC]

hi folks, long time since i posted . So long in fact that the forum design is new to me lol!
Happened to notice telltale tick tick tick sound coming from manifold. Years ago I wrapped the pipes to keep heat down & this had disguised a rust hole right at top of number 4 pipe... I imagine this one gets a little damp when car is standing in rain.
For now I've stuck a little exhaust gum on it as a very temporary measure .
I'm looking for a replacement manifold & what i find on google is SJ's stainless system or Kelvedon's mild steel one ( which i think i prefer ) .
Can anyone add anything to this? Years ago i seem to recall reading about ceramic coated headers ... if you know more pls advise.
cheers
Rich

[jono]

I had a new set of headers made in stainless, slightly oversized, by a firm in Nottingham and then sent them for ceramic coating by a firm called Camcoat.

Brian Clarke off this forum very kindly arranged it all as he was getting a set made for his Sprint at the same time.

Including the coating it was not cheap buy, hey, life is too short to put up with half measures

I think it all cost juts shy of ?500. Te coating was around ?180 I seem to recall.

Jon

[RichC]

thx. what's your opinion regarding stainless v mild steel then, regarding stress cracks ?
I understood that stainless was more prone.
Ceramic coating is on outside only, yeah?
....what about mild steel with ceramic coating then....
I agree no point in half measures ... do it properly and u do it once .
Rich

[rgh0]

Stainless is more prone to cracking in vibrating service. Typically they are also made of thinner material so more delicate and harder to weld.

Personally I prefer a good mild steel set that is ceramic coated.. The coating guy I use at least does them both inside and out. The ceramic coating is not as good a heat insulation as wrapping them with tape but it sure looks nicer and protects the steel when done on the inside by keeping it cooler

I then use a stainless steel tail pipe and muffler.

cheers
Rohan

[Jeff@Jae]

When we were having Elan headers made (1.5" OD primaries, 4/2/1 design) we did them in mild steel and ceramic coating inside and out. They seem to last forever and the reduced heat in the engine bay is very nice.

[RichC]

thanks guys,
took the quick route and ordered standard double s manifolds from susan miller. were with me in under 48hrs .
apparently she doesn't do mild steel anymore 'cos her supplier priced themselves out of market .
they look very nice for ?180 (exl vat)..
Gonna wrap them with some titanium fibre tape before assembling...it came thru this morning from someone online

[AHM]

Before you exert too much effort check that the flanges are true.

Some years ago I bought one from Double S and they weren't so it went back - the second one was ok but still needed filing.

[RichC]

well AHM I guess you were right. Quite surprised how the flanges didn't sit flush, but then with the long primaries i thought it okay to torque down the bolts to pull them up tight. Bit of a job & i hadn't realised how messy the old titanium /fibreglass wrap was until i removed the old manifolds. Each manifold was ripe with rust & was holed at the join with its flange. I suspect that the titanium wrap was instrumental in causing this by holding moisture. It's also quite fragile after a few years in place and falls to pieces when rubbed. The whole car & myself were covered in a fine gold dust of the old dsintegrating titanium wrap and I itched like hell for a day afterwards.
What i noticed straight away was that the manifolds Susan Miller sent me were the same OD as my old stainless steel Y piece and that the old mild steel manifold was smaller OD .
Susan sent me overnight a new Y piece which was much better made and had a bigger lumen than the old one (which was quite narrow and restricting). I don't know if it was for this reason but the performance of the engine has been transformed ! I was certainly much better able to balance and tune the carbs
The double S manifold ends did not end together ..they needed cutting - one about 1 cm the other about 2cm in order for the exhaust to fit . ( siting the transverse silencer dictated the exact length).
Can't fault Susan for her 100% customer service .
They say you can be certain of only 2 things in life ...death & taxes.
I'd like to propose a third ...efficient service from Susan