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Hi All, I'm about to add an engine to my '71 SB and have a question. Can you hop up motor and still run the FI? I've fallen in love with the FI on my son's '69SB and want to keep it on my car. As I understand the FI, it is working mainly on the manifold pressure. This seems to be based on the idea that the manifold pressure would exactly relate to actual volume of air passing throught the intake tubes. So. . . it seems that if I added large valve, hi flow heads and a mildish cam to take advantage of the flow, the FI system would compensate and continue to add in just the right amount of fuel. The BMEP would stay the same, only at higher RPM's, thus giving more power. I guess the specific questions would be: 1. If I keep the displacement the same, can I add a mild cam (275-285 degrees, like in a Porsche 912) and hi flow heads with the same compression ratio, will the FI work? Target red line would be about 5200 rpm. 2. What happens if I increase compression, or achieve the same result by ceramic coating piston domes and combustion chambers? 3. Will the FI work with an increase in displacement? 4. I see two easy ways to make adjustments to the FI, by fooling with the Pressure sensor, and with the fuel pressure regulator. Upping the fuel pressure would seem to richen the whole range from idle to WOT. I'm not exactly sure how fooling with the Press sensor would affect things. 5. I remember reading at some point in the past that there was a company somewhere on the west coast that could rebuild the ECU, onyone know who that was and if they are still around? Any comments or experience about this would be greatly appreciated. I know, it sounds like I wanna be a darksider and not, like having my cake and eating it too. :o) My sons '69SB just runs better and better, the more miles we put on it. I think it had been running terribly rich for some long period of time before we got it, and perhaps we are dong the proverbial "hi rev tune up" now that the mixture is right again. Anyway, it sure is a fun car to drive. I much prefer driving it over my LS400 Lexus. Thanks in advance, Jim Showker '57 based Manx type buggy '69 SB stock '71 SB stock (parts) '71 SB w/ T4 motor (not running) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~