could someone tell me were i can find 1/8" thick tubing in mild steel with a outer diameter of 1 3/4" or 1 7/8".
thanks for your help.

 

Hedman Headers 18 gauge. I know they offer weld up complete "kits".

 

1/8" thk? .125" ? that's about 11awg.
18awg is very thin, .049". Ok for headers, but not if you're going to hang anything off it (a turbo for examble - since this is the power adder section...)

Phone up your local steel place, see what they say.

 

For turbo headers, I've used 14ga from Stan's headers without a turbo support (small single turbo) with no problems.

For N/A I've used Columbia River Mandrel Bends (they are cheaper than Stan's for thin wall).

Both have good service, friendly on the phone and have lightning fast shipping.