Originally Posted by mytmousemalibu

Well, as this car is, errr....was, my daily driver, I'd like to have it back under that moniker asap. There is some urgency besides my desire to turn the key the first time! I really want to get all the major internal engine work done so that I hopefully don't even need to open the engine up again. Exterior parts I might give passage to for the sake of getting it going. Like sticking the stock 603 pump on it for temporary. If I can, it'll go to Sweden to visit Goran before the first start I was thinking about trying to use the stock exhaust manifold as an interim part but the outlet is so pitifully small and I'm going to use a 60mm inducer Turbonetics T60-1 with a T4 flange. So it would require a goofy adaptor tube, plus adding a wastegate port, etc, etc. And all that when I want to replace it with a proper pulse tuned header down the road.... I'll just save the delay and build the header now. More work and money but such is life...

I don't think theres nearly enough room to cut 1/4" out of it. I was rather disappointed by how dinky it was and the non-standard 3-bolt pattern. You might be able to improve it a little bit, get a porting kit, some flapwheels, etc. Not going to get to all of it. I don't know what a manifold would cost but I had ExtrudeHone do my Duramax injector nozzles, honed 50% over stock, and it cost me north of $600 It's not cheap, its a really good service but yeah. I would guess about $300-400 to hone one of those. About 1/3 to 1/2 the cost of a header if you bought one. I did a little reading on the STD forum and supposedly the max seen made with a stock manifold was about 450hp. I wonder what the EGT's were! Thats all hearsay. I did also have the idea of cutting off the stock 3-bolt flange about flush with the tubes and buying a cast iron T3 or T4 adaptor off fleabay and cutting one end of it off and match fit the holes. Either me or someone experienced with welding cast weld it up. Need a proper preheat and post heat which the best I could do is my shop stove