Mine are mild steel, made by Tim Holt. He'd only just started building them when I bought mine, but planned to try stainless.
holtsampson@aol.comI bought a couple of pre-formed mild steel bends, (about 5 to 10 quid each. Plenty of suppliers on Ebay etc). Shortened the manifold pipe & welded the bend on.
OJZ Engineering supplied the stainless bends for my truck project.
http://www.ojzengineering.co.uk/product.php?product=3The EBay Merchant is pauline holt
Email address is
david.holt.wood@talktalk.netand the guy I am dealing with is called Tim.
'Sounds like the same guy to me'