Hey why don't you guys try a weiand manifold http://store.summitracing.com/partdetail.asp?part=WND%2D7516&autoview=sku This manifold makes power from 1500 to 7000 rpm right out of the box and it's cheap. It fits the CHI-3V heads with the CHI spacers that they make and 15 min of port matching perfectly. I have this setup on my 398 Cid. motor. It fits under the stock screen and is also fuel injected .Let me know if you need any more info on this.
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