Thanks Grumpy. I hope that I've helped cure this XT of what its flow ceiling. The as cast tests I've seen with it show what can only be described as a ceiling or plateau where it really hits the wall. While the XT 435, Eddy's own crate motor using the XT manifold, power cuts off at 6K. It makes 442 hp, but drops like a rock from about 5K. The same was true of the 383 install. That one used a too small cam for the heads and short runner intake, but I still blame the runners for much of the low ceieling that motor displayed. It is too bad I don't have before and after dyno results. Still, my own experience tells me that this intake should know support 6,500-6,800rpm from a 350 and 6,300-6,500 from a 383. Peak torque may not have moved much from the 5K it has shown in previous installs, I expect though that the bulk of under curve torque will have moved northward 500+rpm. I know that I probably moved the torque more than I had originally intended. Since this intake will find its way onto a largr motor in a few years, I'm not too worried about it. As I said from early on, this is a bit of old school work here. No solid data on my heads and no flow bench or dyno to quantify the results. I can think of a few 5th gen Camaro owners however that will come to fear this little 355 after it runs past their LS3s at the dragstrip. That will just have to be proof enough of my results.
Here are photos of the second pair of runners, #s 6 & 8. I still have smoothing and radius work to do. Some detail work still to do where the rear of runner #8 meets the rear plenum wall.
Here are photos of the second pair of runners, #s 6 & 8. I still have smoothing and radius work to do. Some detail work still to do where the rear of runner #8 meets the rear plenum wall.