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To gain power at low RPM on a DOCH you want to advance the intake cam and retard the exhaust. This improves low speed driveablilty and fuel economy but hurts high engine speed performance.
Of the 4 valve opening and closing events, the closing of the intake valve has the greatest effect on engine performance. The other 3 open/close events pale in comparison. That is why VVT works so well even on single cam engines. Being able to control intake valve timing is far more important than exhaust valve timing.
Retiming the cam will have the most effect for good around 3400rpm or below and will have bad effects mostly isolated to above 3600rpm.
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1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
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