scarecrowX

okay, the one thing i haven't read anything about yet as far as manifolds is the issue of warping. i'm not a very good welder (i was gonna have a friend weld it for me) but i wanna know if any of you guys have had problems with the head flanges warping. i still have the stock manifolld for my integra, maybe i could bolt the flange to that before welding? the head flanges i'm looking at are 3/8" but maybe it would be worthwhile to go for the 1/2" to prevent this... input is much appreciated...

45psi

good idea to bolt to a spare head. that will prevent warping. not sure on the size though. it seems thicker would be better, but why add the weight if 3/8's will do.

Todd

I normally use 1/2".. if you get too much heat in one spot you will get warping. the best bet is to do small areas and let it cool down inbetween welds. Just take your time.

civic_racer

to prevent any warping, get a wet rag and put it over the metal after welding it, thats what i do when welding thin sheetmetal. like a door or some other body part

XDEep

from maximum boost. i need to get me that damn book someday