Thread: I really am idling with 40 degrees advance

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My timing (just measured) is:
24 degrees static at 700rpm
40 static + vacuum at 700rpm
60-62 static + vacuum + centrifugal at 2800 rpm

The cam is Lunati Voodoo 60101
Advertised Duration IN/EX: 256/262
Duration @ .050 IN/EX: 213/219
Gross Valve Lift IN/EX: .454"/.468"
LSA / ICL: 112/108
Valve Lash IN/EX: Hyd/Hyd
RPM Range: 1000-5500

By the way, I was extremely careful to follow the break in to the letter. I'm learning alot, but now I know why people go and buy turn key crate motors. What the hell? It seems just fine, but the numbers just don't add up. I'm losing my motivation real fast with this damn motor.

Now what?

The engine idles ok at the higher advance rate because it takes a while for the lean idle mixture to burn.

Do you have an amplified ignition box
Something along the lines of an MSD6al?
And are you using a dial-back timing light?
Perhaps one of the Penske ones from Sears?

I found when timing my 462" Buick engine (455 series engine) with a Penske dial-back it was off about 20 degrees.
The original timing light - also a Penske - a non dial-back style showed the timing where it should have been.

I've discussed the dial-back timing lights being used with an MSD 6al box on another site (HAMB).
Most of the guys reported that their dial-back lights read the timing correctly and compare favorably with a non dial-back light.

The readings taken on my - owned for a short while, took it back - light was with the dial set at zero and getting the degrees off the degreed dampener.

A couple things you could do.
Take a reading with a standard timing light and see how it compares to the dial-back light if in fact that's what you're using.

The other, time the engine statically at your desired initial advance figure.

The manuals show centrifugal timing starting as low as 430 rpm in some cases so your 700 rpm idle probably has part of the centrifugal timing in.

Timing the engine statically would show you where you're at there.

As far as your cam timing goes, I'm not seeing a crank gear mark other than the yellow or black line in the pic.

Is that a 350 or a 305? They take different timing tabs and yours sounds like it may be a 305

The timing mark on the lower gear is a small circle obscured by the paint pen. I put in a better pic, you might be able to see it. Black mark is the keyslot I marked.

I have only an HEI with integrated (high voltage) coil. No MSD or dial back light. Using a standard timing light with the marks on the balancer up to 50(double checked against an 8" timing tape).

You may be right about the centrifugal, but would be surprised if it was that much difference down that low. I will try to get it to idle even lower.

On a separate note, I noticed my fuel pressure was very low (recent change showing 1-2PSI). I just thought I would mention it in case that had any impact on this. It might even be a bad gauge.

350 engine. Not 305 (pretty sure).

Thanks Pnut - I see the mark now.

Are you running a mechanical fuel pressure gauge with isolater for the gauge?
The isolaters I've been involved with usually make the gauge show 1# low in the 4# - 6# region.
And if they're full of air or entrained with air bubbles on the gauge side they'll show 1/2# - 1#.

If you're running a Holley red (street) electric pump sometimes the built in regulator hangs up due to roughness in the bore.

I had one do that and it stayed at 1/2# - 1# for quite a while.
I thought the gauge was bad, but nailing the throttle drained the float bowls fairly quick.

Easy to fix by dis-assembling the regulator and polishing - by hand - the regulator piston bore with some 400 - 600 grit wet/dry.

Clean well when done and it will pump pressure good as new - provided it was the regulator that was hanging up.

Most Holley fuel pump failures - and probably other brands - are caused by low voltage at the pump.
Long run of small wire etc.

Do you have a picture of the front of the engine? timing tag- vibration dampner?

I dropped off my Jeep with a friend of mine with a shop. He does lots of carb'd engines and Jeeps.

While talking to him, I think we figured it out. I checked that the marks on the balancer were right. I DID NOT check if the pointer was pointing to 0 at TDC. Both of us were almost sure that was it (since engine is original, and everything else is aftermarket, they may not line up correct).

I'll let you guys know.