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Need help tuning!!!

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  • Need help tuning!!!

    Hi:
    I am a new member, retired and 66 years old and I hope to get some advice from fellow members. I purchased a 1969 ProStreet Opel GT last fall, I have worked on it this winter on many issues(more than 200!!) that had to be fixed. I have finished car this week. I want to do everything RIGHT on engine tuning. I am new to supercharged cars, but not new to race cars, show cars, etc. I have had race cars with Hilborn injectors so I know a little bit on tuning, but nothing on superchargers! The engine in the car is 540ci Dart “Big M” block with Edelbrock “Victor” Heads. The supercharger is BDS 8:71 with 2- Holleys 750’s double pumpers 4160 single power valves. I have tried to find who built engine but have had no luck. The engine is maybe 5 years old. I can give some information on facts of engine that I have figured out. I have rebuilt carbs with new gaskets, power valves,etc I did not change any of the jetting. The carbs are jetted;

    Front carb: .074 primary jets .091 secondary jet 30 cc accelerator pump (primary) 50cc accelerator pump(secondary) .031 pump shooter
    Rear carb: >.074H primary jets .092H secondary jets 30cc accelerator pump(primary) 50cc accelerator pump(secondary) .031 pump shooter.
    Both carbs have Boost referenced power valves (6.5) (The engine builder did this right ,I have read on internet on how to do this and everything is machined and plugged correct for manifold reference under blower). I do not know if he has the right jetting, power valves, etc.
    I did not have enough time this year to check what cam is in engine. I was told it is a Crane. I checked lift with my dial indicators and found….. Intake .683 lift Exhaust .658 lift….. The valve lash was .028 on all valves. This seem to be a very Hot cam for the street to me. Next year I want to install a more mild cam for street only, not racing. The rockers are Crane Roller (1.7) with Competition girdle. I could see the best on everything was put in engine built.
    Ignition is
    MSD Distributor Pro-Billet #85551 MSD 6AL #6420 box I changed over (previous had flying magnet crank trigger) to Mechanical advance in distributor from BDS recommendations, running 22’ initial 34’ total all in by 3000
    I changed rear end gears (Ford 9” Strange engineering axles Detroit locker) with 3:15 for street use. The transmission is as 4 speed Lenco. It had a 3:89 (spool) rear gear but it has so much power I do not need that low of a gear for street and do not need the spool for street. The car will only be for street use mainly going to car shows. It has a aluminum radiator and will run all day at 160’!!! I only drove car last year for 1 hour so do not know how reliable it really is!! I will be testing next week.

    I would appreciate any information anyone could help me with!!!!
    (1.) I would like to know if any one is running this combination and are the jets, carbs in the ballpark?
    (2.) What is the difference on .074 jets and .074H jets?
    (3.) Any other ideas or recommendations?
    (4.) Anything I should watch out for?
    (5.) Is this cam too hot for street only?
    (6.) Thank you very much, Jim
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