I have a 340 of unknown origin with stockish heads 525 solid cam 248@ .050.I am currently using a 3310 vacume secondary 750 holley and I can't seem to get the timing right.I have to retard the timing to stop detonation but that leaves me with not enough initial.......thoughts?BTW using a msd dizzy Pro billet ? Mech advance only ? If so, you can use a combination of the springs and bushes included to get the most suitable advance curve. Edit: Link to instructions: https://documents.holley.com/frm29056_8534_85345_8543_8544_0817.pdf
Last edited by Tig; 09/24/23 08:04 AM.
'74 Challenger..9.46 @ 145.9 1/4, 6.001 @ 118 1/8 so far. 4023lb !!! # N/A, Marsh performance 655ci, Indy Maxx, T/R, Indy 600-13 X's, Street legal, pump gas, full interior, Cal-Tracs, mufflers, 3:73's and real 10.5 radials.
9.51 @ 142.4 1/4, 6.003 @ 114 1/8 with our old mule KB, 572-13, 580 wedge.
RHD '68 Barracuda Fastback 323ci street/strip. Best ET 13.88 @ 99.03
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