Timming...how do I set it?.

[eightbanger]

Ok I did a search on this and not much luck so I've got to ask. Does anyone know how to set the timming on a 454 with HEI?

This is what I know....
Truck up to temp and in idle, attach timming light and connect to #1 lead, disconect Vac hose and plug end of vac hose, point light at timming mark then loosen Distributer and adjust if wrong, then take a reading with the Vac hose attached and adjust Distributer accordingly...BUT...this is were I don't know what the reading should be and when, and what position I should have the Dial set on the timming light to even take the reading, and in what order I should do any of this.
Below are some pics of what I have now, using 0 and 36 on the Dial of the timming light. I just chose to set it at 36 on the light cause I thought I read it somewhere, I have not touched anything yet and untill someone can tell me if the readings I have are even wrong and what I should be doing to get the correct readings then I won't go near it.

Vac hose on and 0 on Dial


Vac hose on and 36 on Dial


Vac hose off and 0 on Dial


Vac hose off and 36 on Dial

[haysonj]

set your light between 8 & 12 and the mark should line up with 0 or if you know the year of the 454 look up in book what the timing is supposed to be and set that on your light. 36 would be full advance under load

[eightbanger]

Originally Posted by haysonj

set your light between 8 & 12 and the mark should line up with 0 or if you know the year of the 454 look up in book what the timing is supposed to be and set that on your light. 36 would be full advance under load

Thanks haysonj, if I set the light between 8-12 should the mark be at 0 when the Vac hose is on or 0 when it is off and plugged?
I think it's 78/79 crate so i'll google that and see what comes up unless someone here knows.

[haysonj]

Originally Posted by eightbanger

Thanks haysonj, if I set the light between 8-12 should the mark be at 0 when the Vac hose is on or 0 when it is off and plugged?
I think it's 78/79 crate so i'll google that and see what comes up unless someone here knows.

Off and plugged 79 454 is 8 degrees

[eightbanger]

Thanks again mate...i'll do that when I get home from work tomorow, and see what reading I get then.

[Jtrux]

Generally the numbers in the book are good to go by, but different engines might be a little different, when you get the hang of it, you can really fine tune it and get it running like a top.

[redhead69]

The 36 your are referring to is your total timing. To set that with an advance light you would dial in 36.. run your rpms up to 3k and turn your dizzy till your mark lines up with zero. If your timing is not locked out by 3k rpms you need lighter springs in your dizzy. Bring it back to idle, and return your light to zero.. your balancer mark will indicate a number (probably between 8 and 12 as stated) this is your new base timing. Test drive and listen for pinging under load!! Retard if necessary. I know small blocks like 36 degrees timing (generally) but not sure if big blocks like the same?? never had one.

[eightbanger]

This is great you guys, I am now a wiser man..."I hope". Gonna have a go armed with all this new info. Though you'll probably hear back from me if I bugger it up.

Thanks very much.

[Lippyp]

Useful info as I will need to do mine soon when I fit my edelbrock performer eps and replace my mallory twin point dizzy with a facotry HEI setup, although mines a small block not a big block.

[Mudder]

Good thread.

[eightbanger]

OK...here are some pics of my timming after using the advice given above.

First pic is with the dial on the light set between 8-12 Degrees, I chose 10 with Vac hose off and plugged.


And this is with the same setting...10 Degrees, but with Vac hose attached.


This one is with 3k on the tach and 36 Degrees set on the light.


I'm pretty happy with how it's set up it idles good and under load too, but if anyone can see from looking at the pics that my timming marks are a bit out...then please chime in on this..

[redhead69]

What rpms did it stop advancing?
Did you run the rpms up with the vacuum plugged?

[eightbanger]

I had my son sit in the cab and keep the RPMs at 3,000 while I took the reading with the Vac on...problem was he's only twelve so I think he found it hard to keep the pedal steady, he said it kept moving from about 28k-32k.

Thanks redhead69 your right from what you said origianaly it should be at 0 while I got 36 on the dial, so i'll have another go and report back.

[Lippyp]

You could try just screwing the throttle stop in/out to set the idle at the right RPM to set the timing and then adjust it back again. Works well when you're working solo.

[eightbanger]

Hi Phill, it is awkward doing this on my own. And that's the thing when doing your timming there so many bloody variables and diferent things you can do which can change the reading. Bought a new toy today that measures my Vacuum...just to throw another thing in the mix....not sure if this really matters as far as the timming is concerned, but anyway I hooked it up and these are the readings.

At idle


And at 3k on the Tach


According to the read outs marked on the gauge my engine when in the Red is in poor conditon. To be at optimum the needle would have to sit between 18-22.

[Lippyp]

My understanding is that the wilder the cam the less vacuum you get so that will have a bearing too. I'm in the same boat as you really, I've done plenty with four pot motors, can balance twin SU's by ear but this is my first V8 so its all new. Got loads to do to mine over the winter as its been off the road a couple of years now due to various things including the wife having twins start of last year. A big block must be nice having driven a friends 68 Impala with a tweaked 454 under the hood the torque is awesome compared to my small block although even thats no slouch at the lights..

[cruiserman]

You're getting more vacuum at 3000RPM than at idle?

Maybe I'm reading it wrong, but you have more advance with the dizzy vac line plugged than hooked up to the dizzy (referring to post 11)?