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It's all in the timing!


FuzzFace2

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They might work. You can check their tension by hooking one of them to one of the existing springs and pulling to see which one gives first. Obviously that is the one that will let the timing advance faster.

But, there's also the length. IIRC, one of the springs has an oversized loop on one end that lets the other spring control everything until you hit the end of the loop So the length has to be right as well.

You are correct, the heavier (high rpm advance) spring has a longer loop which (a) serves as the stop for the low rpm advance and (b) can be made longer or shorter during manufacture to change the amount of initial advance.

Unfortunately, other than the GM top weight models, in order to change the springs or weights involves disassembly and reassembly of the internal parts, and is best done with a distributor machine. I had a nice Allen one from my old shop that the clamp was bad on and the elevation mechanism used to compensate for different shaft lengths was frozen from not being used for years. I had it at a friend's shop in Suffolk, where we took it apart for repair. Somewhere in the time from taking it apart to repair and going back over there it disappeared. He swears I came and got it. It would do 9000 engine rpm, but was only for breaker point systems. Part of the disassembly was to see if it could be modified for breakerless systems, probably with an HEI module.

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You are correct, the heavier (high rpm advance) spring has a longer loop which (a) serves as the stop for the low rpm advance and (b) can be made longer or shorter during manufacture to change the amount of initial advance.

Unfortunately, other than the GM top weight models, in order to change the springs or weights involves disassembly and reassembly of the internal parts, and is best done with a distributor machine. I had a nice Allen one from my old shop that the clamp was bad on and the elevation mechanism used to compensate for different shaft lengths was frozen from not being used for years. I had it at a friend's shop in Suffolk, where we took it apart for repair. Somewhere in the time from taking it apart to repair and going back over there it disappeared. He swears I came and got it. It would do 9000 engine rpm, but was only for breaker point systems. Part of the disassembly was to see if it could be modified for breakerless systems, probably with an HEI module.

I had time and help from my son to get the timing curve I have now so lets see if I can get it posted up.

Idle is @ 800 RPM, timing @ 16* BTDC, vacuum @ 19 HG steady.

No vacuum hooked to dist.

Idle 800 RPM - 16*

1000 RPM - 18*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 24*

3000 RPM - 24*

Vacuum hooked to dist. and adjustment all the way CCW

Idle 800 RPM - 16*

1000 RPM - 16*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 32*

3000 RPM - 34*

Vacuum hooked to dist. and adjustment all the way CW

Idle 800 RPM - 16* - 18*

1000 RPM - 20*

1500 RPM - 26*

2000 RPM - 30*

2500 RPM - 51*

3000 RPM - 51*

It looks all timing is in by 2200 to 2300 RPM

Vacuum to dist. starts at 1600 RPM - just starts to move vacuum gauge

vacuum to change timing starts @ 2300 RPM @ 11 to 12 HG

vacuum to change timing @ 2200 RPM @ 9 HG with adjustment all the way CCW

vacuum to change timing @ 1900 RPM @ 2 HG with adjustment all the way CW

I bumped the timing back to 10* BTDC and left the vacuum hooked up, all the way CW to see what happens when I take it out next time. I will plug off the vacuum if pinging get bad like I did before.

Even with the vacuum disconnected I had pinging with timing @ 16* BTDC

So where do I go from here :nabble_anim_confused:

Thanks

Dave ----

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I had time and help from my son to get the timing curve I have now so lets see if I can get it posted up.

Idle is @ 800 RPM, timing @ 16* BTDC, vacuum @ 19 HG steady.

No vacuum hooked to dist.

Idle 800 RPM - 16*

1000 RPM - 18*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 24*

3000 RPM - 24*

Vacuum hooked to dist. and adjustment all the way CCW

Idle 800 RPM - 16*

1000 RPM - 16*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 32*

3000 RPM - 34*

Vacuum hooked to dist. and adjustment all the way CW

Idle 800 RPM - 16* - 18*

1000 RPM - 20*

1500 RPM - 26*

2000 RPM - 30*

2500 RPM - 51*

3000 RPM - 51*

It looks all timing is in by 2200 to 2300 RPM

Vacuum to dist. starts at 1600 RPM - just starts to move vacuum gauge

vacuum to change timing starts @ 2300 RPM @ 11 to 12 HG

vacuum to change timing @ 2200 RPM @ 9 HG with adjustment all the way CCW

vacuum to change timing @ 1900 RPM @ 2 HG with adjustment all the way CW

I bumped the timing back to 10* BTDC and left the vacuum hooked up, all the way CW to see what happens when I take it out next time. I will plug off the vacuum if pinging get bad like I did before.

Even with the vacuum disconnected I had pinging with timing @ 16* BTDC

So where do I go from here :nabble_anim_confused:

Thanks

Dave ----

Dave, I tried the Mr Gasket distributor spring kit on my 460. And it pinged or knocked worse.

As I’ve been fixing things on this truck I keep finding more. Familiar tune on this forum I think.

I could get it to almost stop knocking when timed at 8°. Disconnecting the vacuum advance didn’t make a difference.

Decided to order a recurved distributor from Scotty the mad porter, Parkland Auto Machine in Tacoma Washington. I heard of him on here. He only had small cap distributors and I got one.

Installed it, still had knocking. Finally after trying different timing settings, contacted Scotty via email (he’s been very helpful), he asked if I tried disconnecting the vacuum advance, I said no I had tried it before with no success, but I would. And sure enough it quit knocking. He said to adjust the vacuum advance, I don’t think it’s adjustable because I couldn’t get an allen wrench to fit, the one in my original distributor adjusted easily with a 3/32 allen I believe. I told him I had no success but did have one I could install and would try when we got better weather and the holidays are over.

Also he asked what temperature of thermostat it had in it, I said 195°. He said to try a 180° because he’s seen these big iron heads knock with 195° thermostats in them. I hadn’t thought of that. So because of the EGR being disconnected and now blocked off, it’s harder to get this 460 from knocking.

So I’ll try a 180° thermostat and get the vacuum advance adjusted when I can and hopefully get the total timing up around 35°.

Thought I’d mention this in case it helped.

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I had time and help from my son to get the timing curve I have now so lets see if I can get it posted up.

Idle is @ 800 RPM, timing @ 16* BTDC, vacuum @ 19 HG steady.

No vacuum hooked to dist.

Idle 800 RPM - 16*

1000 RPM - 18*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 24*

3000 RPM - 24*

Vacuum hooked to dist. and adjustment all the way CCW

Idle 800 RPM - 16*

1000 RPM - 16*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 32*

3000 RPM - 34*

Vacuum hooked to dist. and adjustment all the way CW

Idle 800 RPM - 16* - 18*

1000 RPM - 20*

1500 RPM - 26*

2000 RPM - 30*

2500 RPM - 51*

3000 RPM - 51*

It looks all timing is in by 2200 to 2300 RPM

Vacuum to dist. starts at 1600 RPM - just starts to move vacuum gauge

vacuum to change timing starts @ 2300 RPM @ 11 to 12 HG

vacuum to change timing @ 2200 RPM @ 9 HG with adjustment all the way CCW

vacuum to change timing @ 1900 RPM @ 2 HG with adjustment all the way CW

I bumped the timing back to 10* BTDC and left the vacuum hooked up, all the way CW to see what happens when I take it out next time. I will plug off the vacuum if pinging get bad like I did before.

Even with the vacuum disconnected I had pinging with timing @ 16* BTDC

So where do I go from here :nabble_anim_confused:

Thanks

Dave ----

Dave - We need to discuss the ignition timing in two stages, initial + centrifugal, and then that + vacuum.

Your initial was 16 degrees and your centrifugal was another 8 degrees at 1500 RPM, for a total of 24 degrees by 1500. Compare that to David's timing of 14 degrees initial and 10 degrees of centrifugal @ 1700, giving a total of 24 degrees but at 1700 instead of 1500.

So your centrifugal is coming in earlier than his, but the total isn't too bad. However, dropping back to 10 degrees is probably going to hurt your power and gas mileage.

I would focus on the initial + centrifugal for the moment and drive with the vacuum disconnected. Check to see if at 10 initial you get pinging w/o the vacuum, and note at what RPM you get it. If no pinging, bump the initial up to 12 degrees and go for a drive. Then 14 and test it. You need to determine how much total timing you can handle - without vacuum.

As for the vacuum, it doesn't matter what the RPM is, it'll advance the timing the same at 800 RPM as at 8000 RPM if you give it the same vacuum.

So the key here are these two statements:

  • vacuum to change timing @ 9 HG with adjustment all the way CCW

  • vacuum to change timing @ 2 HG with adjustment all the way CW

And you said that with full vacuum the total timing was 51 degrees, so the vacuum advance gives you a total of 27 degrees all in. That is probably going to be a problem as David's vacuum advance gave a max of 18 degrees. And that may be too much. But the vacuum advance unit can be limited or changed out, so we can deal with that - once we have the initial + centrifugal sorted.

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I had time and help from my son to get the timing curve I have now so lets see if I can get it posted up.

Idle is @ 800 RPM, timing @ 16* BTDC, vacuum @ 19 HG steady.

No vacuum hooked to dist.

Idle 800 RPM - 16*

1000 RPM - 18*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 24*

3000 RPM - 24*

Vacuum hooked to dist. and adjustment all the way CCW

Idle 800 RPM - 16*

1000 RPM - 16*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 32*

3000 RPM - 34*

Vacuum hooked to dist. and adjustment all the way CW

Idle 800 RPM - 16* - 18*

1000 RPM - 20*

1500 RPM - 26*

2000 RPM - 30*

2500 RPM - 51*

3000 RPM - 51*

It looks all timing is in by 2200 to 2300 RPM

Vacuum to dist. starts at 1600 RPM - just starts to move vacuum gauge

vacuum to change timing starts @ 2300 RPM @ 11 to 12 HG

vacuum to change timing @ 2200 RPM @ 9 HG with adjustment all the way CCW

vacuum to change timing @ 1900 RPM @ 2 HG with adjustment all the way CW

I bumped the timing back to 10* BTDC and left the vacuum hooked up, all the way CW to see what happens when I take it out next time. I will plug off the vacuum if pinging get bad like I did before.

Even with the vacuum disconnected I had pinging with timing @ 16* BTDC

So where do I go from here :nabble_anim_confused:

Thanks

Dave ----

Two questions.

1) Are you running an OE stock smog head? I assume you are.

2) Is the 51* total at 3,000 rpm a cruise setting or is it what it flashed to when reving to 3,000?

If you are going down the road pulling in 51* total timing at 3,000 rpm with light load I dont believe that is too much to cause pinging with OE heads. My 351W with the economizer vacuum valve pushes my light load advance at idle to 54* I think it is at 750 rpm idle with no sign of pinging.

I look forward to hearing what you find when you go run the truck around with the 10* initial and full cw adjustment on the vacuum advance.

That is one thing I think I am going to have to fine tune on my truck is the vacuum advance as I know mechanically its going to be limited to 32* - 34* advance to prevent ping under load. Not sure how far I can go with vacuum advance to dial it in.

Dave, I tried the Mr Gasket distributor spring kit on my 460. And it pinged or knocked worse.

As I’ve been fixing things on this truck I keep finding more. Familiar tune on this forum I think.

I could get it to almost stop knocking when timed at 8°. Disconnecting the vacuum advance didn’t make a difference.

Decided to order a recurved distributor from Scotty the mad porter, Parkland Auto Machine in Tacoma Washington. I heard of him on here. He only had small cap distributors and I got one.

Installed it, still had knocking. Finally after trying different timing settings, contacted Scotty via email (he’s been very helpful), he asked if I tried disconnecting the vacuum advance, I said no I had tried it before with no success, but I would. And sure enough it quit knocking. He said to adjust the vacuum advance, I don’t think it’s adjustable because I couldn’t get an allen wrench to fit, the one in my original distributor adjusted easily with a 3/32 allen I believe. I told him I had no success but did have one I could install and would try when we got better weather and the holidays are over.

Also he asked what temperature of thermostat it had in it, I said 195°. He said to try a 180° because he’s seen these big iron heads knock with 195° thermostats in them. I hadn’t thought of that. So because of the EGR being disconnected and now blocked off, it’s harder to get this 460 from knocking.

So I’ll try a 180° thermostat and get the vacuum advance adjusted when I can and hopefully get the total timing up around 35°.

Thought I’d mention this in case it helped.

Are you running a new distributor? I hear a lot of the new distributors are not that accurate on the mechanical advance aspect. The guy who will be recurving my 85 mustang 302HO Cardone distributor informed me of that said that he will have to start off by welding the spring notches up and recutting them to get them where they need to be for my engine build.

Temp wise on the thermostat it can have knocking with too much timing and a 195* thermostat or a carbon up cylinder with a 195* thermostat that bumps compression up. I have installed a failsafe high flow 195* thermostat installed in my 302 build since I am going aftermarket EFI, but I am making sure the recurving of the distributor is taking everything into account from the deletion of all emission systems, the use of higher compression aluminum heart shaped chambered heads and a aftermarket roller cam. Why I will just be letting this guy work his magic on my distributor then I will take over fine tuning the light load advance via the adjustable vacuum advance.

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I had time and help from my son to get the timing curve I have now so lets see if I can get it posted up.

Idle is @ 800 RPM, timing @ 16* BTDC, vacuum @ 19 HG steady.

No vacuum hooked to dist.

Idle 800 RPM - 16*

1000 RPM - 18*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 24*

3000 RPM - 24*

Vacuum hooked to dist. and adjustment all the way CCW

Idle 800 RPM - 16*

1000 RPM - 16*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 32*

3000 RPM - 34*

Vacuum hooked to dist. and adjustment all the way CW

Idle 800 RPM - 16* - 18*

1000 RPM - 20*

1500 RPM - 26*

2000 RPM - 30*

2500 RPM - 51*

3000 RPM - 51*

It looks all timing is in by 2200 to 2300 RPM

Vacuum to dist. starts at 1600 RPM - just starts to move vacuum gauge

vacuum to change timing starts @ 2300 RPM @ 11 to 12 HG

vacuum to change timing @ 2200 RPM @ 9 HG with adjustment all the way CCW

vacuum to change timing @ 1900 RPM @ 2 HG with adjustment all the way CW

I bumped the timing back to 10* BTDC and left the vacuum hooked up, all the way CW to see what happens when I take it out next time. I will plug off the vacuum if pinging get bad like I did before.

Even with the vacuum disconnected I had pinging with timing @ 16* BTDC

So where do I go from here :nabble_anim_confused:

Thanks

Dave ----

Two questions.

1) Are you running an OE stock smog head? I assume you are.

2) Is the 51* total at 3,000 rpm a cruise setting or is it what it flashed to when reving to 3,000?

If you are going down the road pulling in 51* total timing at 3,000 rpm with light load I dont believe that is too much to cause pinging with OE heads. My 351W with the economizer vacuum valve pushes my light load advance at idle to 54* I think it is at 750 rpm idle with no sign of pinging.

I look forward to hearing what you find when you go run the truck around with the 10* initial and full cw adjustment on the vacuum advance.

That is one thing I think I am going to have to fine tune on my truck is the vacuum advance as I know mechanically its going to be limited to 32* - 34* advance to prevent ping under load. Not sure how far I can go with vacuum advance to dial it in.

Dave, I tried the Mr Gasket distributor spring kit on my 460. And it pinged or knocked worse.

As I’ve been fixing things on this truck I keep finding more. Familiar tune on this forum I think.

I could get it to almost stop knocking when timed at 8°. Disconnecting the vacuum advance didn’t make a difference.

Decided to order a recurved distributor from Scotty the mad porter, Parkland Auto Machine in Tacoma Washington. I heard of him on here. He only had small cap distributors and I got one.

Installed it, still had knocking. Finally after trying different timing settings, contacted Scotty via email (he’s been very helpful), he asked if I tried disconnecting the vacuum advance, I said no I had tried it before with no success, but I would. And sure enough it quit knocking. He said to adjust the vacuum advance, I don’t think it’s adjustable because I couldn’t get an allen wrench to fit, the one in my original distributor adjusted easily with a 3/32 allen I believe. I told him I had no success but did have one I could install and would try when we got better weather and the holidays are over.

Also he asked what temperature of thermostat it had in it, I said 195°. He said to try a 180° because he’s seen these big iron heads knock with 195° thermostats in them. I hadn’t thought of that. So because of the EGR being disconnected and now blocked off, it’s harder to get this 460 from knocking.

So I’ll try a 180° thermostat and get the vacuum advance adjusted when I can and hopefully get the total timing up around 35°.

Thought I’d mention this in case it helped.

Are you running a new distributor? I hear a lot of the new distributors are not that accurate on the mechanical advance aspect. The guy who will be recurving my 85 mustang 302HO Cardone distributor informed me of that said that he will have to start off by welding the spring notches up and recutting them to get them where they need to be for my engine build.

Temp wise on the thermostat it can have knocking with too much timing and a 195* thermostat or a carbon up cylinder with a 195* thermostat that bumps compression up. I have installed a failsafe high flow 195* thermostat installed in my 302 build since I am going aftermarket EFI, but I am making sure the recurving of the distributor is taking everything into account from the deletion of all emission systems, the use of higher compression aluminum heart shaped chambered heads and a aftermarket roller cam. Why I will just be letting this guy work his magic on my distributor then I will take over fine tuning the light load advance via the adjustable vacuum advance.

Rusty, yes I told Scott what I had before he recurved the distributor. It is a new one.

I may send him my original to recurve because the small cap bugs me a little.

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Dave, I tried the Mr Gasket distributor spring kit on my 460. And it pinged or knocked worse.

As I’ve been fixing things on this truck I keep finding more. Familiar tune on this forum I think.

I could get it to almost stop knocking when timed at 8°. Disconnecting the vacuum advance didn’t make a difference.

Decided to order a recurved distributor from Scotty the mad porter, Parkland Auto Machine in Tacoma Washington. I heard of him on here. He only had small cap distributors and I got one.

Installed it, still had knocking. Finally after trying different timing settings, contacted Scotty via email (he’s been very helpful), he asked if I tried disconnecting the vacuum advance, I said no I had tried it before with no success, but I would. And sure enough it quit knocking. He said to adjust the vacuum advance, I don’t think it’s adjustable because I couldn’t get an allen wrench to fit, the one in my original distributor adjusted easily with a 3/32 allen I believe. I told him I had no success but did have one I could install and would try when we got better weather and the holidays are over.

Also he asked what temperature of thermostat it had in it, I said 195°. He said to try a 180° because he’s seen these big iron heads knock with 195° thermostats in them. I hadn’t thought of that. So because of the EGR being disconnected and now blocked off, it’s harder to get this 460 from knocking.

So I’ll try a 180° thermostat and get the vacuum advance adjusted when I can and hopefully get the total timing up around 35°.

Thought I’d mention this in case it helped.

Thanks as every little bit helps if not me maybe someone else.

I dont have "big iron heads" but 1 long iron head on this 300 six motor.

Like you I do have the EGR blocked off and I have heard that a working EGR keeps the combustion temps down.

I also have a 195* stat and hate to go colder as I have "milk shake" going on on the oil fill cap & the dip stick tube and think running cooler would only make it worse?

Thanks

Dave ----

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Dave - We need to discuss the ignition timing in two stages, initial + centrifugal, and then that + vacuum.

Your initial was 16 degrees and your centrifugal was another 8 degrees at 1500 RPM, for a total of 24 degrees by 1500. Compare that to David's timing of 14 degrees initial and 10 degrees of centrifugal @ 1700, giving a total of 24 degrees but at 1700 instead of 1500.

So your centrifugal is coming in earlier than his, but the total isn't too bad. However, dropping back to 10 degrees is probably going to hurt your power and gas mileage.

I would focus on the initial + centrifugal for the moment and drive with the vacuum disconnected. Check to see if at 10 initial you get pinging w/o the vacuum, and note at what RPM you get it. If no pinging, bump the initial up to 12 degrees and go for a drive. Then 14 and test it. You need to determine how much total timing you can handle - without vacuum.

As for the vacuum, it doesn't matter what the RPM is, it'll advance the timing the same at 800 RPM as at 8000 RPM if you give it the same vacuum.

So the key here are these two statements:

  • vacuum to change timing @ 9 HG with adjustment all the way CCW

  • vacuum to change timing @ 2 HG with adjustment all the way CW

And you said that with full vacuum the total timing was 51 degrees, so the vacuum advance gives you a total of 27 degrees all in. That is probably going to be a problem as David's vacuum advance gave a max of 18 degrees. And that may be too much. But the vacuum advance unit can be limited or changed out, so we can deal with that - once we have the initial + centrifugal sorted.

Gary you are right this needs to be done in stages.

I did not look at the readings all that close yesterday but you say "1500 RPM" and I was getting pinging below that and even above that with no vacuum.

If runing down the high way at 1800 RPM (or a little more) and floor it I would get pinging.

I would like to get the initial timing back up to 168 but 148 would not be that bad either but I know that 10* its at now is going to kill power.

At the 16* the truck started so nice cold & hot. Cold tap the pedal to set choke, not even put fuel in the intake, tap the key and it fires right up, hot dont need to hit the pedal just tap the key.

I also have a little dieseling at the 10* that I did not have at 16* and the idle RPM is lower now, that is strange?

Guess I have a little work ahead of me. Need to get that spring kit and and may pick up a new vacuum advance unit for this truck as I am sure the one one it is for a car.

Thanks

Dave ----

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I had time and help from my son to get the timing curve I have now so lets see if I can get it posted up.

Idle is @ 800 RPM, timing @ 16* BTDC, vacuum @ 19 HG steady.

No vacuum hooked to dist.

Idle 800 RPM - 16*

1000 RPM - 18*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 24*

3000 RPM - 24*

Vacuum hooked to dist. and adjustment all the way CCW

Idle 800 RPM - 16*

1000 RPM - 16*

1500 RPM - 24*

2000 RPM - 24*

2500 RPM - 32*

3000 RPM - 34*

Vacuum hooked to dist. and adjustment all the way CW

Idle 800 RPM - 16* - 18*

1000 RPM - 20*

1500 RPM - 26*

2000 RPM - 30*

2500 RPM - 51*

3000 RPM - 51*

It looks all timing is in by 2200 to 2300 RPM

Vacuum to dist. starts at 1600 RPM - just starts to move vacuum gauge

vacuum to change timing starts @ 2300 RPM @ 11 to 12 HG

vacuum to change timing @ 2200 RPM @ 9 HG with adjustment all the way CCW

vacuum to change timing @ 1900 RPM @ 2 HG with adjustment all the way CW

I bumped the timing back to 10* BTDC and left the vacuum hooked up, all the way CW to see what happens when I take it out next time. I will plug off the vacuum if pinging get bad like I did before.

Even with the vacuum disconnected I had pinging with timing @ 16* BTDC

So where do I go from here :nabble_anim_confused:

Thanks

Dave ----

Two questions.

1) Are you running an OE stock smog head? I assume you are.

2) Is the 51* total at 3,000 rpm a cruise setting or is it what it flashed to when reving to 3,000?

If you are going down the road pulling in 51* total timing at 3,000 rpm with light load I dont believe that is too much to cause pinging with OE heads. My 351W with the economizer vacuum valve pushes my light load advance at idle to 54* I think it is at 750 rpm idle with no sign of pinging.

I look forward to hearing what you find when you go run the truck around with the 10* initial and full cw adjustment on the vacuum advance.

That is one thing I think I am going to have to fine tune on my truck is the vacuum advance as I know mechanically its going to be limited to 32* - 34* advance to prevent ping under load. Not sure how far I can go with vacuum advance to dial it in.

Dave, I tried the Mr Gasket distributor spring kit on my 460. And it pinged or knocked worse.

As I’ve been fixing things on this truck I keep finding more. Familiar tune on this forum I think.

I could get it to almost stop knocking when timed at 8°. Disconnecting the vacuum advance didn’t make a difference.

Decided to order a recurved distributor from Scotty the mad porter, Parkland Auto Machine in Tacoma Washington. I heard of him on here. He only had small cap distributors and I got one.

Installed it, still had knocking. Finally after trying different timing settings, contacted Scotty via email (he’s been very helpful), he asked if I tried disconnecting the vacuum advance, I said no I had tried it before with no success, but I would. And sure enough it quit knocking. He said to adjust the vacuum advance, I don’t think it’s adjustable because I couldn’t get an allen wrench to fit, the one in my original distributor adjusted easily with a 3/32 allen I believe. I told him I had no success but did have one I could install and would try when we got better weather and the holidays are over.

Also he asked what temperature of thermostat it had in it, I said 195°. He said to try a 180° because he’s seen these big iron heads knock with 195° thermostats in them. I hadn’t thought of that. So because of the EGR being disconnected and now blocked off, it’s harder to get this 460 from knocking.

So I’ll try a 180° thermostat and get the vacuum advance adjusted when I can and hopefully get the total timing up around 35°.

Thought I’d mention this in case it helped.

Are you running a new distributor? I hear a lot of the new distributors are not that accurate on the mechanical advance aspect. The guy who will be recurving my 85 mustang 302HO Cardone distributor informed me of that said that he will have to start off by welding the spring notches up and recutting them to get them where they need to be for my engine build.

Temp wise on the thermostat it can have knocking with too much timing and a 195* thermostat or a carbon up cylinder with a 195* thermostat that bumps compression up. I have installed a failsafe high flow 195* thermostat installed in my 302 build since I am going aftermarket EFI, but I am making sure the recurving of the distributor is taking everything into account from the deletion of all emission systems, the use of higher compression aluminum heart shaped chambered heads and a aftermarket roller cam. Why I will just be letting this guy work his magic on my distributor then I will take over fine tuning the light load advance via the adjustable vacuum advance.

Rusty,

1) First this is a 300 six motor if that makes a difference.

I would think it is a smog head as the motor I think came from a car based on the exh. manifold I pulled off after the 81 head pipe would not fit it. I am running EFI exh manifolds and factory pipes less cat.

Also the motor color, gray, I dont think was used on 81 truck 300 six motors?

So yes on smog head, no smog equipment on motor, EGR blocked off.

2) I dont know if you would call that "flash" at 3000 RPM but was not driving down the road LOL

It was 51* at 2500 RPM and I believe it was in by 2300 RPM from what testing I did.

With vacuum hooked it either CCW or CW the pinging was really bad. With vacuum disconnected it was a lot less but still there.

As Gary pointed out mechanical is coming in at 1500 RPM and at 45 / 50 MPH I am below that in OD.

So I will work on getting this up to about 1700 / 1800 RPM with out vacuum and see if that stops the pinging with out vacuum then move on the vacuum advance.

Thanks

Dave ----

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Rusty, yes I told Scott what I had before he recurved the distributor. It is a new one.

I may send him my original to recurve because the small cap bugs me a little.

Was he just out of the large cap dist. or he dose not do them?

Cant you use the adapter the large cap uses to fit the small body to run the large cap?

Thought that is all Ford did?

Wait the dist. that uses the adapter screws to the dist. the small body dist. uses clips right? :nabble_smiley_blush:

Dave ----

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