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Old 06-27-2017, 12:51 AM   #1
88Stanger
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Join Date: Mar 2015
Location: Washington State
Posts: 1,644
help with new 383 stroker issue

sorry it is a bit long.....

background: 383 eagle specialties stroker kit -
5.7 i-beam rods
new crank
floating pin pistons with 12cc dish/valve reliefs
block .040 overbore
block clearance for stroker motor
Edelbrock head gasket - 4.125 bore with .041 compressed thickness
Edelbrock aluminum RPM heads with 70cc
Edelbrock aluminum RPM air-gap intake
large try y headers
Howards full roller cam and lifters
219 degrees @ .050 = intake
225 degrees @ .050 = exhaust
525 lift
106 intake lob centerline
110 separation
Fitech 600hp power adder system with FCC
full MSD new ignition, billet dist., coil, wires, and MSD6AL box
should be about static compression ratio = 10.0 to 1
initial timing set to 14 degrees
compression check = all 8 cylinders avg 190lbs

issue: starts and idles, but if you stab the gas pedal it pukes up and out the carb. i have removed the MSD and replaced with 1 wire HEI, still did it, removed the FI-Tech system and installed a 600cfm carb and it still did it. i Called Howards and talked with them on it and they suggested that the cam is too small and could be the cause of very high compression numbers (190lbs) and this with the smaller duration causing the higher compression and then forcing a backfiring up and out the carb.
Does this make any sense to anyone?!?!
any help is greatly appreciated!!
sorry this is so long.
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