360 Tune Up

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mullinax95 said:
You might interested in this. Worked great on my distributor.
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Glad it worked for you. But its backwards for most factory distributors. Study the graph and you'll see why. Limiting the secondary spring shifts the curve up. Then its too much mechanical for using with vac advance in the mid rpms and retards with slew on the drag strips.
 
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Mattax said:
Glad it worked for you. But its backwards for most factory distributors. Study the graph and you'll see why. Limiting the secondary spring shifts the curve up. Then its too much mechanical for using with vac advance in the mid rpms and retards with slew on the drag strips.
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Guess I don't understand. The plate does exactly same thing but not having to weld up the slots. It's also adjustable.
 
mullinax95 said:
Guess I don't understand. The plate does exactly same thing but not having to weld up the slots.
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Don's plate stops the advance. To then get the initial and maximum where they should be, the distributor has to be rotatated. That shifts whole curve up. Alternatively the springs can be messed with and thats not easy for most folks. The secondary spring is the most critical and hardest to find for an advance that's been stopped early.

Welding up the inside of slots it cuts off the bottom of the timing curve. For most electronic distributors, that's it, all done. Curve is still correct when the initial is set like a pre-CAP engine (or higher initial if its hot cam).
 
Mattax said:
Don's plate stops the advance. To then get the initial and maximum where they should be, the distributor has to be rotatated. That shifts whole curve up. Alternatively the springs can be messed with and thats not easy for most folks. The secondary spring is the most critical and hardest to find for an advance that's been stopped early.

Welding up the inside of slots it cuts off the bottom of the timing curve. For most electronic distributors, that's it, all done. Curve is still correct when the initial is set like a pre-CAP engine (or higher initial if its hot cam).
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I understand now. You're welding up the inside of slots not the outside.

I installed different springs. Vacuum advance is plugged off. Initial is 16 and 34 at 3500 I believe that's right... been awhile since I tinkered with it.
234/238 .571/.576 roller cam
4speed
 
mullinax95 said:
I understand now. You're welding up the inside of slots not the outside.

I installed different springs. Vacuum advance is plugged off. Initial is 16 and 34 at 3500 I believe that's right... been awhile since I tinkered with it.
234/238 .571/.576 roller cam
4speed
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I got a lil less cam and similar timing.
 
Mattax said:
Don's plate stops the advance. To then get the initial and maximum where they should be, the distributor has to be rotatated. That shifts whole curve up. Alternatively the springs can be messed with and thats not easy for most folks. The secondary spring is the most critical and hardest to find for an advance that's been stopped early.
Click to expand...

Thank Mattax ! I have the limiter plate but have yet to install it. Now I'm going to weld my inner slots. Good Info.
Rock Able, I hope the pulley does the trick for you. I thought for sure your shroud was the culprit blocking flow on highway but the FABO menbers here are much more knowledgeable than myself and will for sure get this figured out with you. Sweet ride you got there.
I always thought A/C water pumps move coolant slower so the radiator can cool down more and not send coolant back through hot but I don't really know .
 
I took it for a drive today and drove it in lower gears and same speed. This has the effect of increasing rpm and water pump speed. Result - nada. Same temps as before. So, the pulley thing is not my problem, apparently.

I spoke to George at Champion Radiators later. His suggestion is that my shroud is restricting flow at speed. He wants me to remove the shroud and do some testing. On a 41 Plymouth, this is much easier said than done. After I get finished dreading it, I will do it and let you know what I find. Thanks for all your help.
 
Kendog 170 said:
I always thought A/C water pumps move coolant slower so the radiator can cool down more and not send coolant back through hot but I don't really know .
Click to expand...

At one time I followed the same logic but that's not how it works. Heat is always transferred the fastest when there is the largest difference in temperature; the hotter the antifreeze in your radiator (OR the colder the air outside), the faster the heat is being absorbed by the air flowing through the fins. So you actually want the coolant flowing faster so that the temp of the water in the rad is always as high as possible; that will reject the most heat. This is also why using a colder thermostat actually puts more load on your cooling system and can make it easier for your engine to overheat. The t-stat opens when the coolant in the block gets up to temp and lets the coolant circulate until the whole system cools down again; that takes longer the lower the temperature the t-stat is rated for.

@Rock Able just try to imagine being able to cruise worry-free and not have to even think about cooling issues. I have to replace the whole radiator, fan, add a thinner fan clutch, and add a solid motor mount in my Duster because I had an incident a couple weeks back where a worn mount allowed the engine to move and the fan hit the top tank and sliced a huge gash in the core of my new ECP aluminum radiator. So I have an idea of your pain lol.
 
MopaR&D said:
At one time I followed the same logic but that's not how it works. Heat is always transferred the fastest when there is the largest difference in temperature; the hotter the antifreeze in your radiator (OR the colder the air outside), the faster the heat is being absorbed by the air flowing through the fins. So you actually want the coolant flowing faster so that the temp of the water in the rad is always as high as possible; that will reject the most heat. This is also why using a colder thermostat actually puts more load on your cooling system and can make it easier for your engine to overheat. The t-stat opens when the coolant in the block gets up to temp and lets the coolant circulate until the whole system cools down again; that takes longer the lower the temperature the t-stat is rated for.
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Good to know. I'm old school but open minded I love learning stuff from this site ! Thanks
 
I'd try living with it and doing some more monitoring.
As long as it doesn't creep up 210 is fine.
On the measurement side,
Might boil some water and hang the sensor in it to confirm 212 is close to 212.
Most thermometer devices are not particulaly accurate.
Might add an oil temperature gage. That's another really useful indicator of how the engine is managing heat.

Check system pressure is holding.

Is there any sceening of the radiator in front? I know its likely but figured I'd mention it. Screens start to look like walls the faster its moving.

Poking around Speedtalk, there's discussions of coolant temperatures up to 230-240*F can be fine, depending the pressure. That is there has to be enough system pressure to keep it from boiling at those temperatures.
Chevy at 220- 230 Coolant Temp - Page 2 - Speed Talk

Engine wear, test summary quoted from Stockel on page 2.
optimum coolant temp for longevity - Speed Talk

Distilled Water? - Page 2 - Speed Talk
Sequence of failure when coolant overheats? - Speed Talk

This guy was worried about 220, so some of it is personal tolerance, and again what the system can handle.
PONTIAC 350, circle track race engine, RUNNING HOT. - Speed Talk
 
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Too late. Removing it wasn't as big a deal as infrared. (Hardly ever is.) I've made a new mount and will give it a try today.
 
Shazam! Took the shroud off, fabricated new mounts and took it for a spin. At 70 mph, 91 degrees ambient, it stayed on 180! I guess my homemade shroud was too shallow and too restrictive after all. Looks like it will stay cool when idling with the A.C. on, as well. Thanks for everyone help And suggestions!

Now, I'm anxious to test that mileage.
 
That's interesting.
I'm sure you can come up with a modified or partial shroud if needed for sitting still.
 
Funny, I can be right with other peoples problems but can't fix my own lol. Glad you got it figured out .
 
Hi Guys. Reopening this thread because it's been pretty informative for what I am trying to do.
After about 700 miles on my fresh 5.9 Magnum build I figured I would do some fine tuning.
It 's a .030 mild 218/226, air gap, 600cfm with headers. Stock electronic ignition. Has a 904 and 3.55's.
Initial timing I have been running was at around 16 degrees at 650 rpm. No issues.
Started my tuning and it appears my advance timing is coming in really fast.
Measured with dist vacuum disconnected and plugged. engine warm.
After build:
650 rpm. 16 deg
1000. 20
1500. 27
2000. 34 full advance

Yesterday I drove the car and adjusted distributor seat of the pants for best performance and measured again.
650. 25 deg
1000. 27
1500. 32
2000. 39
2200. 40 maxed

I must admit that I am no expert at ignition timing and usually set it and then adjust to what feels right and leave it.
I do have a vacuum gauge and set carb mixture at highest reading. Any thoughts on what I am seeing and how best
to set this up for best overall performance for street/highway/twisties?
 
JoePole1 said:
Hi Guys. Reopening this thread because it's been pretty informative for what I am trying to do.
After about 700 miles on my fresh 5.9 Magnum build I figured I would do some fine tuning.
It 's a .030 mild 218/226, air gap, 600cfm with headers. Stock electronic ignition. Has a 904 and 3.55's.
Initial timing I have been running was at around 16 degrees at 650 rpm. No issues.
Started my tuning and it appears my advance timing is coming in really fast.
Measured with dist vacuum disconnected and plugged. engine warm.
After build:
650 rpm. 16 deg
1000. 20
1500. 27
2000. 34 full advance

Yesterday I drove the car and adjusted distributor seat of the pants for best performance and measured again.
650. 25 deg
1000. 27
1500. 32
2000. 39
2200. 40 maxed

I must admit that I am no expert at ignition timing and usually set it and then adjust to what feels right and leave it.
I do have a vacuum gauge and set carb mixture at highest reading. Any thoughts on what I am seeing and how best
to set this up for best overall performance for street/highway/twisties?
Click to expand...
Does it ping? 40° total is pretty strong.
 
Another thing to consider is that it's an AC car and I will have to bump the idle speed to about 1000-1200rpm otherwise it wants to die in gear with AC on.
 
JoePole1 said:
Another thing to consider is that it's an AC car and I will have to bump the idle speed to about 1000-1200rpm otherwise it wants to die in gear with AC on.
Click to expand...
A/C cars should have a idle speed solenoid.
 
It's on the "to do" list. Not settled on a carb yet. Currently Edelbrock 1903 600cfm. Also have 670 Street Avenger but just picked up an 850 Thermoquad that needs going through.
 
JoePole1 said:
Hi Guys. Reopening this thread because it's been pretty informative for what I am trying to do.
After about 700 miles on my fresh 5.9 Magnum build I figured I would do some fine tuning.
It 's a .030 mild 218/226, air gap, 600cfm with headers. Stock electronic ignition. Has a 904 and 3.55's.
Initial timing I have been running was at around 16 degrees at 650 rpm. No issues.
Started my tuning and it appears my advance timing is coming in really fast.
Measured with dist vacuum disconnected and plugged. engine warm.
After build:
650 rpm. 16 deg
1000. 20
1500. 27
2000. 34 full advance

Yesterday I drove the car and adjusted distributor seat of the pants for best performance and measured again.
650. 25 deg
1000. 27
1500. 32
2000. 39
2200. 40 maxed

I must admit that I am no expert at ignition timing and usually set it and then adjust to what feels right and leave it.
I do have a vacuum gauge and set carb mixture at highest reading. Any thoughts on what I am seeing and how best
to set this up for best overall performance for street/highway/twisties?
Click to expand...
Well that's about everything opposite and diffferent than what @Rock Able was doing and did.

If you're jumping on this thread it might pay to go back and see what he did.
it turned out timing was not the primary problem, but he squared it away in the process of figuring out the cooling issue.
 
I found this thread by search hence "360 Tune-up" and my timing issue applied except the OP had low initial timing and it appears that my initial is high. The thread then morphed into a cooling issue after the timing was squared away. If I am off base I will start another thread.
 
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