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Topic Review (Newest First)
01-01-2019 05:48 AM
MonzaRacer i set gears at dot to dot, then crank engine over till #1 intake is closing then with cut down clothes hanger or other simple rod hold against piston as someone turns crank with wrench till piston comes all the way up(slows down as it hits tdc.
Also one handed use a starter button and crank till compression pushes finger off plug hole and then creep up. The timing mark should be at/near tdc.
Most big blocks I have tuned under 11-1 we have good gas and I generally set 14deg up to edge of timing tabe which if right is usually about 18deg. On HEI I make sure to piggy back new 12 guage wire from firewall connector to HEI plug. I just remove bulkhead connector, remove wire from connector. If I have spare 52 series connectors I will simply remove braided covered resistor wire and install new IGN wire, If customer doesnt want that terminal removed and folded back I also open strain relief tabs, with cleaned terminal and some liquid flux Ill lay my 12 ga wire under strain reliefs and solder it on top of the crimps. Push that black gooey crap back around and tape wire to the harness or few small zip ties depending on length of time it may stay HEI.
New HEI plugs are available everywhere.
I always crimp as solder electrical stuff.
On street engines with moderate cams STOCK HEI weights with lightest springs in Accel kit or MSD kit works well. Make sure the centrifugal stop bushing is present on bottom stop pin of distributor. 14-18 initial and the light spring generally give best road performance w/limited track. Listen for spark knock, starter buck.
After setting timing and adjusting carbs idle mixture and speed, THEN hook vacuum advance up to manifold vacuum. and readjust final carb adjustments.
This generally gives you proper off dyno starting place. If you get spark knock, hard surging or starter buck pull 2 deg initial. If you total goes past 55-58 you have distributor stop bushing issues or long travel vac advance. or possibly the vacuum advance can is adjustable for maxlength through vac hose port.
Again I like 53-58 MAX advance at 2500-3000 vac advance hooked to manifold vacuum(revs up engine and timing goes up) What vacuum advance is for is mileage. and you want it to DROP when you open throttle.
In car way to dial in initial and centrifugal is start at 14 and advance 2 degrees till it bucks starter hot, back off 4 deg. This is base and can be tweaked as needed.
Centrifugal advance needs to be in BY CRUISE RPM IE 55mph=2800 or just below. or what ever your final gear gives you at 55mph.
Then adjusting mechanical/centrifugal max with stop bushing. and mixing and matching springs, I sart tose with both lightest then swap in on light one medium, then two medium etc. BUT best seat of pants/track time dial is a working from their.
Adjusting max mech advance and initial for best 60 ft/ET. Street cars can keep vac advance line on as open throttle negates it if vac adv spring is good.
Some cars with lumpy cam racing needs vac line removed and plugged.
07-01-2018 09:13 AM
daturbosix
Quote:
Originally Posted by Blownbyyou View Post
So disconnecting the vacuum advance puts the timing in normal range... wtf
base timing should always be set with vacuum advance disconnected
06-30-2018 09:33 PM
Blownbyyou So disconnecting the vacuum advance puts the timing in normal range... wtf
06-25-2018 08:42 PM
Ti28 That key way should be in the 12 o'clock spot. Line cam and crank up dot to dot. Distributor pointing at number 1.


Hard to tell from the pic where the dots are.

TDC 1 both rockers should be loose.
06-25-2018 04:45 PM
Blownbyyou
Quote:
Originally Posted by Mr_Roboto View Post
https://www.youtube.com/watch?v=RENhHI9n65I

Go buy a piston stop and establish TDC. I think the Comp one I have was $15ish.

You probably have a mix of early pointer (which was located at 2:30 or so till 1969) and late balancer (which was located at 12:00.)

http://www.crankshaftcoalition.com/w..._TDC_lines_SBC
THANK YOU! I am thinking this is why all the numbers are way the eff off. If the pointer and the balancer dont match then no one knows what the fuck is going on lol!

I told him to order a new balancer and pointer and will reply with findings..
06-25-2018 12:00 PM
Blownbyyou Yeah thats why he is confused as fuuuu lol.... I am going to see if he will adjust the distributor again. But he unfortunately doesn't have a good timing light with advance on it.
06-25-2018 11:59 AM
daturbosix EIGHTY DEGREES ADVANCED?!

turn that bitch back a tooth or two
06-25-2018 11:50 AM
daturbosix batavia 60510
06-25-2018 11:34 AM
Blownbyyou
Quote:
Originally Posted by daturbosix View Post
< this guy
but id prefer it to come to me

also, what kind of ignition are you running? points still, or electronic?
HEI... new distributor.. actually two new distributors lol. . It went to a shop previously (2 shops actually) and they are saying the total advance is around 80 degrees lol.

Where are you at?
06-25-2018 11:02 AM
daturbosix he doesnt really have to find "exact TDC". just pull the cover and watch the rockers on #1 to make sure its left on the ignition stroke.
06-25-2018 10:57 AM
Mr_Roboto https://www.youtube.com/watch?v=RENhHI9n65I

Go buy a piston stop and establish TDC. I think the Comp one I have was $15ish.

You probably have a mix of early pointer (which was located at 2:30 or so till 1969) and late balancer (which was located at 12:00.)

http://www.crankshaftcoalition.com/w..._TDC_lines_SBC

Quote:
The pre-1969 damper has the TDC line on the outer ring at the 2:30 o’clock position- or 2º before the keyway centerline- i.e. the line is to the LEFT of the keyway, looking at the front of the damper or engine. The keyway is seen in the ID of the damper nose. Includes a majority of the 2.30" small journal main engines and the 1967-69 2.45" large journal engines.
The damper used from 1969 to about 1995 (some 1978-86 GM automobiles do not use the 2 o'clock position balancer and associated timing cover where there is some overlap usage e.g. G-series vans which retained the 2 o'clock balancer while the passenger car and C/K light duty trucks transitioned over to the 12 o'clock position which used a centrally located timing pointer spot welded) has the TDC line at the 2 o’clock position- or 10º before the keyway. You'll find that aftermarket dampers are the 10º type, as are the bolt-on tabs sold by the aftermarket, unless they're adjustable. The 2 o'clock position was reintroduced during the 1987 model year trucks with the 8" balancer (only with the LO5-optioned 350/5.7L).
06-25-2018 10:42 AM
daturbosix < this guy
but id prefer it to come to me

also, what kind of ignition are you running? points still, or electronic?
06-25-2018 10:29 AM
Blownbyyou I am 99% sure he has done that (he is pretty good with this shit), Ill have him try again but its to a point he just wants to pay some one lol.


Anyone have any recomendations?
06-25-2018 06:57 AM
IceCreamAssassin
Quote:
Originally Posted by daturbosix View Post
409 in 1966? nah.

if cam timing is correct, then set at TDC on #1 cylinder.
- drop distributor in with rotor pointed towards #1 cylinder
- the closest plug wire to where the rotor is lined up is #1 now.
- 18436572 in clockwise direction on the cap from there
- snug up the distributor hold down, but still be able to turn the distributor
- start cranking it and moving shit until it fires, then jump on the light
-depending on specs of the engine, id say 30 degrees advanced(total) would be a good starting point

Fixed

I’d check and make sure all those wires are in the right place. Also when it’s idling throw a vacuum gauge on it to make sure you have full vacuum and not leaks. It’s also a great way to set a good base timing. Just turn the distributor slowly till you have reached peak vacuum at idle for a good starting point.
06-24-2018 10:22 PM
Blownbyyou
Quote:
Originally Posted by daturbosix View Post
409 in 1966? nah.

if cam timing is correct, then set at TDC on #1 cylinder.
- drop distributor in with rotor pointed towards #1 cylinder
- the closest plug wire to where the rotor is lined up is #1 now.
- 18436571 in clockwise direction on the cap from there
- snug up the distributor hold down, but still be able to turn the distributor
- start cranking it and moving shit until it fires, then jump on the light
-depending on specs of the engine, id say 30 degrees advanced(total) would be a good starting point
Sorry its a 402, dont know why i typed 409 lol.....

The car is in countryside (near la grange), whats weird right now is the rotor is pointing to cylinder 2 and running fine @ idle lol...

We know 0 specs on the engine lol..
06-24-2018 08:44 PM
daturbosix where are you located?
06-24-2018 08:44 PM
daturbosix 409 in 1966? nah.

if cam timing is correct, then set at TDC on #1 cylinder.
- drop distributor in with rotor pointed towards #1 cylinder
- the closest plug wire to where the rotor is lined up is #1 now.
- 18436571 in clockwise direction on the cap from there
- snug up the distributor hold down, but still be able to turn the distributor
- start cranking it and moving shit until it fires, then jump on the light
-depending on specs of the engine, id say 30 degrees advanced(total) would be a good starting point
06-24-2018 08:29 PM
Blownbyyou FYI that picture indicates it’s incorrect as the cam timing was off 180 degrees. It was rectified today with a new timing chain set (fucked up two cars in my family had timing chain issues this month lol)
06-24-2018 08:28 PM
Blownbyyou
Ignition timing on a big block?

Is anyone on here capable and interested in helping me set timing on 66 impala with a 409?

My dad bought this car a while back from a widow of some guy who “restored” it. But turns out he was an alcoholic who really didn’t do much if anything right.


The scenario right now is that the cam timing is set right for a stock cam (Assumed) as we just did it today Attachment 32873. The ignition timing, Is really jacked up and we can’t figure it out. To put it in perspective at idle the timing mark on the balancer is lighting up at 12 o’clock vs 2 o’clock where the timing mark indicator is (hope that makes sense).

Anybody have true knowledge/skill set to help? Or at least point me in the direction of someone who can do it?

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