428 stumble and dyno question
Here is the setup in my 67 GTO convertible.
428 stock rods and crank. .30 over.
#62 heads
1.65 rollers
comp cams xe268h
edelbrock 750 and performer manifold
1 5/8" headers.
PYPES 3" exhaust w/ X pipe
MSD billet distributor set 12 degrees btdc
muncie 4 speed
The car pulls like crazy from around 1500 to about 4000 rpms. The problem is that it has a stumble from the line. If i keep the rpms up before letting off the clutch, its fine. If i take off really really slow, its fine. If I take off normally, it stumbles/bogs, almost to the point of stalling. The guys at the dyno think that it may be a carb/cam combo problem. Also, the HP seems to fall off fairly early if you look at the dyno sheet.
Please have a look and throw me some suggestions if you have some.
thanks,
matt
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