Spark plug reading for timing and correct heat range

[hunt2elk]

Posting this question up in the racers section even though this is just a street driven car. Can any of you give me your opinion if I am close for heat range and timing?
Been messing around with the motor a lot the past couple of years getting it running decent. Found out I had a bad distributor causing most of my problems. Now running a FireCore set at 18 initial and 33 all in by 3400rpm no vacuum advance. The motor runs great with more initial timing, but I have experienced hot starting issues and also run on when turning off. Recently I have installed an AEM air/fuel gauge and have been working on the carb and feel I am getting close. I am putting in a fresh set of plugs this weekend.
Car is a 69 RR, 451 with Source heads, NGK BKR5E #7838 plugs.

 

[dvw]

Are you talking full power? If so make a hard run through the gears with a fresh plug. At the end of the run put it in neutral , shut it off and coast to a stop. Pull the plug you want to read an show it to us. Side view as well.
Doug

 

[lewtot184]

in a street driven car, especially city driving, you spend more time on the idle circuit than you'd think. it's obvious your too rich. pictures not perfectly clear for me but timing looks ok. a vacuum advance may help clean the plugs up; I won't drive without one.

 

[cdr]

in a street driven car, especially city driving, you spend more time on the idle circuit than you'd think. it's obvious your too rich. pictures not perfectly clear for me but timing looks ok. a vacuum advance may help clean the plugs up; I won't drive without one.

As said , I run a vac advance on mine, ported vacuum, 1st I had it bring in 5deg & now have 10 deg,try it you will like it initial 24, total 34, under VERY light cruise 44, it even made the exhaust quieter when on the freeway.

 

[747mopar]

I remember you stating that your vacuum was to low for an advance? I know you probably don't want to throw money at it but I did some looking (you got me curious) and there's a distributor that might help you? MSD makes one that you can electronically simulate a vacuum advance along with the mechanical advance, don't know much about them but maybe somebody who does will chime in.

 

[lewtot184]

I use the mopar stuff. it's simple and adjustable.

 

[Bill Monk]

http://4secondsflat.com/Spark_plug_reading.html

 

[hunt2elk]

I know they look rich, and I have it running leaner all around now according to my new gauge. I am more wondering what you guys think of the 2 timing marks on the strap. And the reason is that I have run the motor with as much as 22 degrees initial and it runs great, but I do get desieling when shutting off. Would a different heat range alleviate that issue?

 

[hunt2elk]

Also don't know exactly what to think about running vacuum anymore. Don at FBO was trying to get me to run it on this motor hooked to manifold. It just plain won't work that way on this motor because it only makes 8.5" at idle. I have run it on ported and may go back to that once I get this tuning straightened out. Brian at IMM Engines just built me a 408 that just flat out rocks. He says there is no way in hell he would run vacuum advance on these motors. After seeing how this 408 runs got me to playing more with the 451 I am inquiring about.

 

[lewtot184]

it seems to be human nature to dislike what you don't understand. anybody who denies the benefits of a vacuum advance on a street car has not seriously worked with them. this head in the box stuff. the only time I can think of to not use a vacuum advance on a street car is if the vacuum is so low it's impossible to use it; and with the units being able to be adjusted down to a low vacuum it makes not trying silly. your 8.5'" of vacuum is not indicative of ported vacuum. do a simple test and hook a vacuum gauge to the ported a nipple, take a drive, and see what it does. if that doesn't satisfy you then hook the vacuum gauge to manifold vacuum and see what that does. this is too easy!

as far as Don wanting you to use manifold vacuum I disagree with that. Don had an article on this website from a GM engineer saying some stuff about ported being strictly for emissions, IIRC. I looked at some older pre-emissions carb info and they all used ported, or at least the info I have does. I limited my comments about this due strictly for my respect for Don. I buy his stuff; 'nuff said.

if you don't try something else then you'll never solve issues. these mopar websites can be a blessing or a curse and firmly believe they are a curse more often than not.

 

[cdr]

As far as desieling, turn the Idle down a little, I will admit i turn mine off in gear.

 

[lewtot184]

I've been fortunate in that I never have dieseling issues with either of my cars. I don't run more than 18 degrees initial on either car. I do think some dieseling is due to dirty combustion chambers. i'm sensitive to dirty chambers but realistic enough to know that this can be a constant battle. I do run fuel cleaners just to help this problem.

 

[67 coronet]

what kind of fuel do you run? todays crap fuel can make fine tuning tuff. how big is your cam? i end up running a bit rich on my street eng to run well.
my 383
93 octain
590 purple shaft flat tappet
22 deg initial, all in 35 at 3200
plugs always read rich and smells like it, but runs like a raped ape.

 

[hunt2elk]

As far as desieling, turn the Idle down a little, I will admit i turn mine off in gear.

I have it at 850 now, which is about as low as I want to go.

 

[hunt2elk]

what kind of fuel do you run? todays crap fuel can make fine tuning tuff. how big is your cam? i end up running a bit rich on my street eng to run well.
my 383
93 octain
590 purple shaft flat tappet
22 deg initial, all in 35 at 3200
plugs always read rich and smells like it, but runs like a raped ape.

91 octane, which is the best we have around here. Can is a Racer Brown ssh-44 hydraulic 242/242 @ .050.

 

[oldbee]

Gotta agree with lewtot, vacuum advance always on the street. Street/strip is always a compromise for what you want.

 

[hunt2elk]

it seems to be human nature to dislike what you don't understand. anybody who denies the benefits of a vacuum advance on a street car has not seriously worked with them. this head in the box stuff. the only time I can think of to not use a vacuum advance on a street car is if the vacuum is so low it's impossible to use it; and with the units being able to be adjusted down to a low vacuum it makes not trying silly. your 8.5'" of vacuum is not indicative of ported vacuum. do a simple test and hook a vacuum gauge to the ported a nipple, take a drive, and see what it does. if that doesn't satisfy you then hook the vacuum gauge to manifold vacuum and see what that does. this is too easy!

as far as Don wanting you to use manifold vacuum I disagree with that. Don had an article on this website from a GM engineer saying some stuff about ported being strictly for emissions, IIRC. I looked at some older pre-emissions carb info and they all used ported, or at least the info I have does. I limited my comments about this due strictly for my respect for Don. I buy his stuff; 'nuff said.

if you don't try something else then you'll never solve issues. these mopar websites can be a blessing or a curse and firmly believe they are a curse more often than not.

I agree with you that vacuum advance should help, but Brian got me nervous about running it on his motor. His reasoning is that you can't always hear the detonation, the advance varies by rpm and load, and vacuum advance was developed only for smog engines when the government was forcing the manufactures to comply with their new emission standards. Not for these higher horsepower motors we are driving.
This 451 in my RR that I am inquiring about in this thread runs fine with the vac hooked up to ported, and I will hook it back up again after getting all this tuning figured out. The problem with hooking this motor to manifold is that the lowest start point on any can made is right around 8". It will start great and then advance to a mid to high 20's. As soon as you put the car in gear and let out the clutch, it hangs up and pulls the idle speed up with it. If you unhook the can it will drop right back to a nice idle.
On the other hand, my Charger with a milder cam with 12" of vac at idle works great hooked up to manifold. Starts at 16*, goes to 24* at idle, and runs strong.
I have hooked a vacuum gauge up in the cabin and drove around recording what the vacuum does in all situations.
As far as Don, I do like his control boxes and use them on all my cars. His distributors, not so much. I can curve them to my cars better than he can on a machine trying to guess what they need. He does have some very strong opinions though and lets you know them.
I am learning more and more about tuning these cars everyday, and enjoying it immensely. Sure wish you or someone with your knowledge lived near me to steer me in the right direction sometimes though....

 

[lewtot184]

whoever told you vacuum advance was developed just for smog engines is a loon.

 

[Budnicks]

 

[coloradodave]

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
What lewtot184 wrote....I don't know about being a loon, but vacuum advance canisters have been around way before anyone was talking about limiting emissions from cars. To give him the benefit of the doubt, maybe he was talking about 'ported' vacuum.

Oh, and thanks, Budnicks, for posting those charts. Great information...