Any timing experts out there that can explain some some timing paremeters

[Rickysnickers]

Originally Posted by 1970-CST

10” of manifold vacuum is pretty low. The 30-30 cam in my vintage vette made 10” and it needed A LOT of timing.

For discussion purposes, that engine (327/365hp 30-30 cam) idles at 1200 RPM, and setting base timing is near impossible, as the mechanical fly weights begin to add centrifugal advance around 700 rpm, lower then engine idles. So setting 10* initial timing was deceiving, as some of that was mechanical. In this case, I unhook the vacuum adv hose, and rev the engine until no more advance is added by the fly weights, in this case that was 2450 RPM. So at 2500 RPM I would move the dist. to set 38* advance.

If I set it at idle, I was leaving 6* of timing on the table, as the fly weights were contributing to the timing at idle. So setting 10* on the tab, was actually 4* base timing. When optimizing for performance, 6* is a HUGE amount.

What is your Idle RPM?

Timing is everything, and all the tuning and widgets to make HP are worthless unless you can optimize the timing map for your particular setup.

One needs to remember that “ported” vac adv, and low initial timing was a bandaid to get the engine across the emissions finish line. It was FAR from optimum.

Here is the engine I am running, https://blueprintengines.com/product...lock-bp4002ct1 . I have the ECU set to idle at around 850 rpm. As per the Edelbrock instructions, the initial timing is set at 12 degrees. This is set for the firing of the injectors and that they are firing correctly. The distributor included with the fuel injection is all electronic. There are no vacuum lines to it at all. The timing and vacuum advance is done through a tablet.