Need Help With Hf Build-up

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My Buddy Mugencrx and I picked up a si head from a 90si hatch with about 50k my friends hf has 170k so we figured when we rebuild your head well swap the si head on well I'm not a D series pro but the head is missing the intake manifold and we have the manifold from a 89 DX hatch will sombody tell me if it will work because I'm worried about the MPFI( we have the DX ecu)
 
first off for the si head to work right with out a wiring hasle you are going to need an si intake manifold and ecu... and if you are going to use the si cam you will need an adjustable cam gear... The DX intake manifold is DPFI and the HF is MPFI, so you will need to at least use the HF manifold but the si manifold is recommended...
 
does your hf have the stock engine in it? if so i would personally use the hf manifold over the dx any day dpfi sucks. get rid of the dpfi and get a si ecu. if using the hf block next problem you'll run into is that the valves will make a lovely tapping sound against the pistons. hf model cars are 8 valve motors, not enough valve reliefs for the 16 valve head. you'll also need si or dx pistons so take your pick.
 
so you guys are saying your gonna need adjustable cam gear and dx or si pistons to make the all motor hf article true????
 
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