I recently bought a 1975 blazer with a SB 400. In the first week I abused it and really the only problem that arose was the timing going out and a tick (sticky valves) in the heads. I planed on rebuilding or replacing the heads anyway so all is good. My problem is related to the conversion to a tpi fuel injection. Can I use a 1986 tpi system directly on top of SB heads or is there more to this swap? Any help or advice positive or negative is appreciated. I have a lumpy cam and I am also not sure of where to go or how to reprogram the computer for these tpi systems. I will probably end up with a westers garage chip. Thanks for any advise.