Ok i just orderded my BP manifold today, and the welder needs a good exhaust flange. i used the search feature and came up with

http://weirtech.ca/
which has mild steel 3/8 flange

http://www.etdracing.com/flanges.html
mild steel but no idea on thickniess?? any one know??

and
http://www.jgstools.com/turbo/mx5bp.html
i was told to stay away from there flange poor round to oval design.

is there any other componys who make flanges? has anyone had any experience with them? the welder wants a 1/2 flange and i think he said it would be better in mild any opinions?

Thanks

 

just stick with wier, you'll be fine with 3/8's
ask the welder to brace the flange, maybe bolt it down to your stock manifold while welding, and have him weld short 1'' lines at a time and you don't have to worry about warping

 

For some reason I'm having a similar issue. For a mild flange I'd recommend Wier. Good guy, and he'll take care of you. I just wish my welder would agree to use a mild flange.

 

Edit: I missed that the OP is looking for a BP flange. This is a B6 flange. I'll leave it here for future reference.

Full-race.com

Head flange for 92-93 Mazda Miata motors. Laser cut from 1/2" 1018 Mild Steel. $50.00

 

Uh, you do know the difference between the B6 and the BP, right?

 

No, I've never heard of either of them.

I missed the BP part.

 

my ETD manifold has a 1/2" flange. presumably their flanges are also 1/2".

http://jgsturbo.com/index2.html has half inch flanges. $78.50

 

Maybe you can get Aaron (wier) to make a one of 1/2" if thats big of a deal.
Or just use the 3/8".

 

doe doe doe people on other boards where saying "3/8 is more then enoguh" i rather go thicker to, i did order the weir one today but maybe ill odred the etd if i can verify that it is a 1/2 in i rather have thicker neukin is building my manifold.

 

To the OP: Go with the Weir for flanges.

I will weld a mild steel flange to your stainless primaries.

 

The way I sometimes think about it (maybe incorrectly) is that the thinner 3/8 flange is closer in cross section to the pipe you are welding to it, so you have more even penetration of the weld, and it's just easier to weld if you're new at it.

 

ok i called etd today and at first the guy said there 3/8 and i asked him to check (he wasnt happy) but it turns out the b6 is 3/8 and the bp is 1/2!! so i ordered that one so now i will have the weir one as a paper weight and the etd for te manifold