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I have a 69 with what I believe to be a 73 454 engine.

It has a cam, head work, headers, dual 4's on a low rise and it's hooked up to a turbo 400. (I don't know the stall speed) I have a 12 bolt with a high, but unknown, numerical gear ratio. (It HAS to be at least 4.11's)

I also just installed a Mallory HEI and new 8.8 plug wires.

I don't intend to race this car.

I need recommendations for plugs and timing. Also, since the old single point came out and it did not have vacuum advance, I haven't hooked it up to the Mallory, either.

I'm a complete newbie at trying to get the timing right. (I know how to set timing, but I don't have an ear for setting it by sound, so I only know how to set it to factory spec which probably doesn't apply here.)

Any ideas would be much appreciated, and thanks in advance.
 

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but I don't have an ear for setting it by sound,
Forget the old school set timing by ear..it is BS

You best bet is set within the ball park, then from there dyno or street test for optimin
Disconnect vac advance, with timing light take the rpms up, check the advance is working, take up to max advance, (about 3000 to 3500 rpm) then set advance to 34 to 36 deg. what is at idle is what u have...
Connect vac advance, and set mixtures for best idle.
 

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with stock heads on my Gen IV, I run the AC R44TS plug, gapped @ .050 (MSD box, GM HEI dist, mechanical advance only). you might want a hotter plug with the dual 4 bbls.
as for the timing question, you need to determine degree @ top dead center, before you can establish a base. (it helps to first determine which plug is TDC~1st fire; mine was timed for #2 plug to be TDC~fired. :clonk:)
for example, mine @ static TDC is 8* after. it started (cranked) good there, but performance wasn't very impressive. (I suppose this number exists due to however and wherever the builder degreed or didn't degree the cam as-to "0" = TDC ?).
I added advance in small increments where I ended-up static @ 14* before the center-line mark on the timing tab.
2500 RPM yields the mark showing (with a timing light) to the left of the timing tab about 1/16th of an inch.
I haven't gone-into the workings of my distributor to know the amount of mechanical advance the weights and springs are giving, but,, I figure, as long as the car starts easy, runs relatively cool, and performs,,, the numbers don't really matter (to me).
if your engine is "noisy", as mine is,, be careful when adding advance, because at~RPM, you won't hear pinging, and you can bend or break something,, like pushrods.
for me, I judge my amount of advance~extreme by how the starter cranks the engine, then back-off a tick. I know this sounds and is probably primitive at best, but all engines that we're dealing with are different by build. what worked in the stock configuration doesn't apply today. myself, I like to adjust by sight, sound and feel.:yes:
inheriting someone else's build sure is fun,, isn't it ?? :thumbsup:
 

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for the love of good, id you have a good timing light that shows advance, FORGET that ridiculous "by-ear" method. Thats the most unserious thing I have ever heard. You want maximum power from your timing, you better get it exactly right.
As suggested try setting the timing at idle so that it totals at 34 degrees at about 3000 rpm. If your mallory distributor is a new one, it will probably have about 16 degrees of mechanical advance in it, so you wil probably need to advance initial timing ( remember time it at 750 rpm MAX ) to about 18 degrees. ( and just for the record, that is not too much, if your engine cranks fine when hot, it likes 18 degrees ). My concern now is that you can set timing to 34 total with no problems, but when you hook up vacuum advance again ( to manifold vacuum VERY important ) it might make your engine stumble at cruise-speeds. You most likely have an adjustable vacuum can, so adjust it to give 16 degrees advance. and your'e ready to go! then you recalibrate the miwture screws!
( Im new in this Forum btw, but i most certainly am not new to tuning V8's:) )
rgds Jacob
 
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