Final thoughts on Exhaust porting
On the 92-95 L27/L67 tubular manifolds, there is the risk of welding the outside of the flange in order to be able to port out the OEM weld on the inside. There is huge advantage to doing this (you can port an extra 16-20% on each pipe outlet).
Our manifolds are gasket-less from the factory. To play it safe, weld like I did in my other topic, 'stitch' welding the outside, and letting it cool in between, or pre-heat the entire assembly first. There is still a risk of warping or misshaping the flange from the localized heat caused by the welder. The best solution at this point is to use manifold gaskets, which are available. This also allows for a little flexing of each manifold to help prevent the cracking problem I found and had repaired.
Mine is going back together with Fel-Pro gaskets from Autozone. They're $8.99, but I don't know if that'* a pair or not. I'll find out when they come this week. FYI, I got every gasket on the engine for under $60.
Gasket maker (tube)
Thermostat housing gasket
Thermostat rubber seal
EGR valve gasket
Exhaust manifold gasket
Timing cover gasket
Water pump gasket (fel-pro, in case the water pump comes with something cheap)
Doughnut gasket for the downpipe to rear manifold
LIM manifold gaskets (4 pieces)
Valve cover gaskets
The only gasket I could not get from there was the TB gasket, and the Supercharger gasket I already got from the dealer.
I'm a firm believer that had the exhaust manifolds come with OEM gaskets, they would not have cracked, or at least not as badly.