Hello all,
I have a 1972 Demon 4 speed, 3.91 gears, with a LA 410 CID stroker, it's 12.3-1 Comp, Ported Eddy heads with 2.055" intake valves, Hughes 242/246 @0.050 cam with 0.587/0.592 lift with Hughes 1.6 shaft rockers, Hughes PN 1129 springs installed with 145# closed pressure and 360# open pressure. Eddy Performer RPM intake port-matched, TTI Step headers with dual 3" exhaust with X pipe and a Gen 1 FAST EZ EFI, FBO Limiter plate in the Dizzy running 20 deg initial advance with 30 deg total. I built this motor about 7 years ago and it has never wanted to rev past 6000rpm I always thought it was a problem with the old Mallary High Fire 6 that was on it (rev limiter set to 7000 in both the High fire and in the EZ EFI). The car Dynoed 416 RWHP and 475 RWTQ so it has always been allot of fun to drive. But I finally got a wild hair and removed the High-fire 6 and installed a NEW FBO box and new coil, and the car idles better on the FBO and seems to have better throttle response but still falls on its face at 6000 rpm. Attached is the Dyno Chart, you can see it droppes off hard like it's hitting a rev limiter. Anybody have experience with a set-up like this with a problem reving? Could be valve float? Performer RPM just cant flow enough? Not Enough cam? I have thought about going to a solid roller the lighter solid lifters may kill 2 birds with one stone...
I know the A/F is kind of all over the place but the old EZ EFI only allows 3 Target A/F , Idle, WOT, and Cruise. No provisions for A/F based on RPM it just tries to reach the target A/F at WOT does not seems to do the best job of it... WOT set to 12.8-1 A/F...
Any help will be appreciated
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