So very stuck...

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TT5.9mag said:
Ok you need to seriously stop messing around and MAKE your timing do what you want it to do. 42 is too much and likely the reason it’s rattling. Forget vacuum advance FOR NOW, after you get a good baseline you can add that in later. Almost any mildly modified street type engine will run pretty good with 18 or so initial and 32 total with one light and one medium spring. So I always recommend that as a starting point. So find a way to limit the mechanical to 14 degrees, set the initial at 18, verify that as you rev the engine it increases to 32 around 3000 rpm or so and then, only then you can start tuning on it.
Click to expand...
Okay, sounds good. I'm going to open up the distributor tomorrow and take a look at the springs. I may have gone light spring and heavy spring, like I said I set the distributor a few years back so I cant remember which springs I used. I will post pictures.
 
R3N0 said:
I was adjusting the distributor by retarding the timing I would start to get a tapping noise. I'm making a guess that it's the rockers, but in all honesty it could be the hydraulic lifters as well.
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Um, which way are you turning the distributor? Sounds like you're dialing in MORE advance until it starts to ping...
 
R3N0 said:
I was adjusting the distributor by retarding the timing I would start to get a tapping noise. I'm making a guess that it's the rockers, but in all honesty it could be the hydraulic lifters as well.
Click to expand...
Got it. So something was making noise. Here’s the deal, timing is not something to dilly dally with. MAKE your timing what you want it to be. The numbers I listed above are a good starting point for a street engine with mild compression and a mild cam. Don’t guess, don’t assume, don’t make it “about” 32 degrees. Set it dead on nuts. Then move on to something else if it still makes noise. Also, before you even begin to set anything, do yourself a favor and verify the TDC mark on the balancer is accurate. If it’s slipped or off a few degrees your timing will never be what you set it to.
 
Okay, so yesterday I spent all day retarding the distributor. My timing mark on the balancer says it is sitting at 5*, I am assuming that with the mechanical advance that means it's about 19*. Is this correct? If so this is where the top end pinging stopped. I changed out the springs in the distributor... my brother who had( and I mean HAD) been helping me with this build apparently put both the silver springs in and I was going all in at about 2300 rpm. It is now back to factory. Both blue springs, going in at about 3000 -3200 rpms. Hes also the one who put the tape on the balancer... which means at this point I'm not even sure that's correct and I will need to get out my piston stop and verify that the balancer is correctly timed as well as not slipping. It is a new balancer, installed when the motor was built. Motor has about 15k-20k miles on it at most. I checked the piston tops with my micro camera through the spark plug holes and no holes thankfully. But I'm pretty sure if I had a hole static timing would not of held at 180 psi. I'm not sure if the videos I upload are providing good enough sound but I'm getting alot of popping above 2k. I'm assuming this means I'm running rich. I can dial that back, as I changed the rods and springs when I noticed that the spark plug was dry and dark brown. I thought I was lean, now im too rich. But the spark plug looks alot better. Had to deal with the shot pump piston as the rubber on it was too large and had bound itself making the truck stutter at take off. Chinese crap. Bought an edelbrock made plunger and installed it. Now theres no more stutter. I will check the balancer and make sure it hasnt slipped when I find my piston stop... buried in my tool box somewhere. So as a summary if I'm correct, I'm at 19* @ idle and 29-30* all in. But pinging is gone on the top end. Now I did hook up the vacuum assist on the distributor and I immediately went from 5* on the balancer to 20* on the balancer...again my brother was playing with this so he may have turned it up, or is this normal? Timing is not my strongest skill and I have alot to learn apparently. But I want to say thank you all for helping and the advice. You guys are two thumbs up in my book.
 
I'm trying to upload a video from youtube I took and posted there... give me a few.

20221023_135014.jpg
 
R3N0 said:
Okay, so yesterday I spent all day retarding the distributor. My timing mark on the balancer says it is sitting at 5*, I am assuming that with the mechanical advance that means it's about 19*. Is this correct? If so this is where the top end pinging stopped. I changed out the springs in the distributor... my brother who had( and I mean HAD) been helping me with this build apparently put both the silver springs in and I was going all in at about 2300 rpm. It is now back to factory. Both blue springs, going in at about 3000 -3200 rpms. Hes also the one who put the tape on the balancer... which means at this point I'm not even sure that's correct and I will need to get out my piston stop and verify that the balancer is correctly timed as well as not slipping. It is a new balancer, installed when the motor was built. Motor has about 15k-20k miles on it at most. I checked the piston tops with my micro camera through the spark plug holes and no holes thankfully. But I'm pretty sure if I had a hole static timing would not of held at 180 psi. I'm not sure if the videos I upload are providing good enough sound but I'm getting alot of popping above 2k. I'm assuming this means I'm running rich. I can dial that back, as I changed the rods and springs when I noticed that the spark plug was dry and dark brown. I thought I was lean, now im too rich. But the spark plug looks alot better. Had to deal with the shot pump piston as the rubber on it was too large and had bound itself making the truck stutter at take off. Chinese crap. Bought an edelbrock made plunger and installed it. Now theres no more stutter. I will check the balancer and make sure it hasnt slipped when I find my piston stop... buried in my tool box somewhere. So as a summary if I'm correct, I'm at 19* @ idle and 29-30* all in. But pinging is gone on the top end. Now I did hook up the vacuum assist on the distributor and I immediately went from 5* on the balancer to 20* on the balancer...again my brother was playing with this so he may have turned it up, or is this normal? Timing is not my strongest skill and I have alot to learn apparently. But I want to say thank you all for helping and the advice. You guys are two thumbs up in my book.
Click to expand...
I should also mention that this is all happening ATDC.
 
You don’t seem to understand how ignition timing and advance (static and mechanical) work. As engine speed increases you need to light the fire sooner (BTDC) to give time for the burn and expansion of gasses to act on the piston at the right time. At idle there should be no mechanical advance. So if it reads 5* then the timing is at 5*. Now if you hooked the vacuum advance to manifold vacuum it will pull in timing at idle. But you should not be concerned with that level of tuning at this point. Unhook and plug the vacuum advance for now. It should not take “all day” to set the timing. Before you do anything else, verify that your TDC mark on the balancer is correct, and that your brother put the timing tape on the balancer correctly. What ignition system and distributor are you using?
 
TT5.9mag said:
All of this should be happening BTDC.
Click to expand...
Okay so, FML. Iether the tape is wrong or the distributor gear is off? I'm gonna say the tape is probably wrong... I'm gonna pray that it's just the tape. I wish I could show the timing tape and light but every video doesnt come out. Any thoughts on next step, I know that I set up the cam with a cam degree wheel. The piston was set to TDC with the cam gear facing #1 sparkplug on the compression stroke. I guess I'm pulling the radiator to get to the balancer and checking that it hasnt moved. I'll take a picture of the tape as it sits on the balancer. I know this doesnt tell you whether or not the tape is in the right position but I think its facing the wrong way now.

20221023_160347.jpg
 
Okay, what I'm saying by " all day" is I would retard the timing a few degrees then test drive, come back retard a few degrees and then test again. No i cant say that i understand timing at this point. When i retard the the distributor its turning clockwise, another indicator that something is wrong as everything I'm reading says it should be CCW. At this point I'm just glad there is no damage to the motor. Everything seems to be intact and together. Now i just need to find a starting point. I'm thinking the balancer. The distributor is a summit racing HEI capped with vacuum advance. Part number 850033 if I remember correctly. And the coil is a MSD.
 
The cam is a comp cam xe256H ,the timing gear had 3 key holes but only 1 that would fit the cam. I cant imagine that the motor is turning backwards and still running, so I'm confused as to why the distributor would be going the wrong way. The manual for the distributor says the #1 wire should be pointing at the #1 piston but in that position is where I'm getting detonation. I'm lost now, I fear I may have to pull the timing cover now. If i remember correctly the balancer only had 1 keyway to insert into, but again it's been a few years and remembering how the balancer sat is lost on me. This truck has been almost a ten year project so it sat for a couple of years at a time.
 
R3N0 said:
Okay so, FML. Iether the tape is wrong or the distributor gear is off? I'm gonna say the tape is probably wrong... I'm gonna pray that it's just the tape. I wish I could show the timing tape and light but every video doesnt come out. Any thoughts on next step, I know that I set up the cam with a cam degree wheel. The piston was set to TDC with the cam gear facing #1 sparkplug on the compression stroke. I guess I'm pulling the radiator to get to the balancer and checking that it hasnt moved. I'll take a picture of the tape as it sits on the balancer. I know this doesnt tell you whether or not the tape is in the right position but I think its facing the wrong way now.

View attachment 1716001907
Click to expand...
When looking at your timing tape picture, the numbers below the 0 are degrees advanced and the numbers above the 0 are degrees retarded. Read your timing tape at the 0 mark of your timing cover.....And no, your engine is not running backwards :)
 
[1] Turning the dist CW retards ign timing. And vice versa.
[2] You are going off in all different directions....& getting nowhere.
[3] First thing to do is understand detonation. It is caused by heat, load & insufficient octane.


-load. It doesn't ping in neutral......because there is very little load on the engine. I will also bet that if you load the engine [ just as a quick test ] when cold it doesn't ping or if it does, only slightly.
- heat. Hypereutectic pistons. They require a very large top ring gap because the crown runs very hot. This is supposed to make more power because the combustion gas stays hotter, less pressure loss. But I often wonder if this makes the engine more detonation prone.
Lean mixture generates more heat, so avoid lean mixture.

[4] Make sure the engine cooling system is efficient. Make sure the rad cap maintains pressure. Make sure you use a t'stat 180 or 160. If the engine runs hot at idle, try a smaller w/pump pulley.
[5] Cold air induction. Not only does it give more hp, but it helps reduce detonation.
[6] Try richening the cruise cct of the carb.
[7] Only after you address the fundamentals above do you start playing with ign timing.
[8] It is mooooooooooost important to have the vac adv working. It should be connected to a manifold vac source [ NOT ported ]. Any port below the t/blades. You can tee into the brake booster port, any man vac port except the PCV line. Why is MVA so important compared to PVA? Because MVA adds timing at idle. PVA does not. The extra idle timing makes the engine more efficient, reduces running temp. If the engine has MVA & has been idling & you give it load, the engine is cooler as the instant the load is applied; it is less likely to detonate. You should have an adj vac unit [ large hex behind nipple ]. Adjust the Allen key fully CW.
[9] This type of engine will likely want about 30-32* of timing at idle. That can be ANY combination of initial + MVA. Since it has a propensity to detonate. I would use 8-10* init + the remainder from MVA [ example, 8* + 22* ]. Most adj VA units have a total of about 30* with the plunger fully deployed. You will need to fabricate a stop to limit travel to 22*. This is ALL part of tuning.
[9] You will need to experiment with the centri curve in the dist. Vac adv drops to zero under load. So if you used 8* init & you want 36* @ WOT, the internal curve needs to be 28*. If you have a GM type HEI dist [ excellent choice ], you can use the two inner holes on the cross bar [ that the rotor attaches too ] with a small nut & bolt to limit total travel. You may have to use stronger springs to delay the advance &/or grind the weights to achieve same.
[10] I doubt your bal has 'slipped'.
 
Okay I found a major opsie, only have myself to blame as I installed the distributor gear. Notice the location of the distributor rotor... this is while the motor is a TDC, so the gear is in the wrong position. I own that. Also the balancer pic is with the motor at TDC on combustion cycle. Do I need to turn the number so they cascade upward instead of downward. The Tstat is a 180, and I'm using the ram jet to bring air into the motor, so in affect it kinda has cold air intake .I no longer get any detonation or ping since i retarded the motor, but with the distributor gear in the wrong position relative to the number 1 piston it's a wonder its firing at all. This would explain why timing is all over the place. The zero on the timing tape and the zero on the timing cover match up at TDC. my thought is is it upside down.

20221023_174940.jpg


20221023_174922.jpg
 
The timing tape only goes to 12* BTDC in the orientation that its taped in.
 
Bewy said:
[1] Turning the dist CW retards ign timing. And vice versa.
[2] You are going off in all different directions....& getting nowhere.
[3] First thing to do is understand detonation. It is caused by heat, load & insufficient octane.


-load. It doesn't ping in neutral......because there is very little load on the engine. I will also bet that if you load the engine [ just as a quick test ] when cold it doesn't ping or if it does, only slightly.
- heat. Hypereutectic pistons. They require a very large top ring gap because the crown runs very hot. This is supposed to make more power because the combustion gas stays hotter, less pressure loss. But I often wonder if this makes the engine more detonation prone.
Lean mixture generates more heat, so avoid lean mixture.

[4] Make sure the engine cooling system is efficient. Make sure the rad cap maintains pressure. Make sure you use a t'stat 180 or 160. If the engine runs hot at idle, try a smaller w/pump pulley.
[5] Cold air induction. Not only does it give more hp, but it helps reduce detonation.
[6] Try richening the cruise cct of the carb.
[7] Only after you address the fundamentals above do you start playing with ign timing.
[8] It is mooooooooooost important to have the vac adv working. It should be connected to a manifold vac source [ NOT ported ]. Any port below the t/blades. You can tee into the brake booster port, any man vac port except the PCV line. Why is MVA so important compared to PVA? Because MVA adds timing at idle. PVA does not. The extra idle timing makes the engine more efficient, reduces running temp. If the engine has MVA & has been idling & you give it load, the engine is cooler as the instant the load is applied; it is less likely to detonate. You should have an adj vac unit [ large hex behind nipple ]. Adjust the Allen key fully CW.
[9] This type of engine will likely want about 30-32* of timing at idle. That can be ANY combination of initial + MVA. Since it has a propensity to detonate. I would use 8-10* init + the remainder from MVA [ example, 8* + 22* ]. Most adj VA units have a total of about 30* with the plunger fully deployed. You will need to fabricate a stop to limit travel to 22*. This is ALL part of tuning.
[9] You will need to experiment with the centri curve in the dist. Vac adv drops to zero under load. So if you used 8* init & you want 36* @ WOT, the internal curve needs to be 28*. If you have a GM type HEI dist [ excellent choice ], you can use the two inner holes on the cross bar [ that the rotor attaches too ] with a small nut & bolt to limit total travel. You may have to use stronger springs to delay the advance &/or grind the weights to achieve same.
[10] I doubt your bal has 'slipped'.
Click to expand...
My air gap manifold has a vacuum tree on it, it most certainly sits below the blades as does the vacuum advance on the distributor, if I tee onto the brake booster above the blades it should be okay place?
 
It doesn't really matter where the rotor is pointing as long as the tower in the cap has the spark plug wire going to #1 cylinder. Having the rotor pointing a little more towards the #1 plug will give you more clearance for the vacuum advance running into the firewall. If you move the intermediate shaft so the rotor points more towards the #1 plug, you will need to pull the plug wires off the cap and rotate one tower. Like I mentioned, the rotor could point towards the firewall as long as the plug wire over the tower on the cap is running to #1 plug while at TDC and you follow the 18436572 firing order. Hope that makes sense!!
 
Like 66fyssh said, the rotor can point any darned place as long as THAT place is where you put #1 plug wire on dist cap. AMD follow cw around cap with 18436572.
66fyssh said:
It doesn't really matter where the rotor is pointing as long as the tower in the cap has the spark plug wire going to #1 cylinder. Having the rotor pointing a little more towards the #1 plug will give you more clearance for the vacuum advance running into the firewall. If you move the intermediate shaft so the rotor points more towards the #1 plug, you will need to pull the plug wires off the cap and rotate one tower. Like I mentioned, the rotor could point towards the firewall as long as the plug wire over the tower on the cap is running to #1 plug while at TDC and you follow the 18436572 firing order. Hope that makes sense!!
Click to expand...
 
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