1978 F-fun hundred 3/4 tons and 37s

Heads arrived. Gotta tear them apart because they weren’t bagged. Quality looks good but they’re full of shipping debris. Maybe I should just clean the popcorn out with a carbide burr???
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Both air filter bases were punched and tapped for 1/8 npt for the pcv fresh air.
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Finished the heat riser today. Final install this weekend when the 1” carb spacer arrives. I’ll test between open and 4 hole. The 4 hole I have actually came off this manifold from my 77 F150. Wondering where that came from. Stock engine ran damn good with this manifold/spacer/1406 carb. Heat riser will be removed in the summer months-Cold air connected.
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Wanted to test out the color match against the harbor freight tool boxes.
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You wouldn’t believe it but I cleaned up the vacuum stuff. It just doesn’t photograph well especially with my other nonsense to clean up.
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Ordered a duraspark distributor from madporter. We discussed the custom tailored timing curve and where he wants my baseline tune. I’m excited to actually know what my timing is. He recommends the 6AL. Another recommendation was staying at 180* thermostat for detonation control. That shortens up my work list.

Next on the purge list is the steering reservoir in favor of an integral model TC pump.

Also dreaming up a coil relocation integrated with the ignition module somewhere and revamping my wiring harness.
 
Did he mention a 160* at all?? Asking for a friend.

I think the carbide bur on a die grinder is the standard recommended method for cleaning up shipping debris.
 
He did not. Asked me what I’m currently running so I mentioned bumping it up and that was a no-go. Very adamant for the 180*. I have the radiator profile fully blocked (corrugated plastic) (there’s an air gap, the plastic isn’t directly on the fins) and it’s warm enough to actually excite the fan now at traffic idle.

Seriously though, one of the roughest castings I’ve had my hands on. No fault of the machine shop. This is a foundry issue. Lots of flash in the water jackets, one intake runner seriously looks full of sand and there’s core shift in the exhaust ports. Might as well grind out the thermactor bumps, port match exhaust and fix intake runner.
 
You can also pull out the valves and port/cleanup the bowls if your that far in. It will make the biggest gain in flow, especially the exhaust side.
 
Thought about going as far as polishing the combustion chamber but that’s an unrealistic investment compared to my list of projects.

A thorough blend job should be sufficient as you mentioned.

Dumping the 1/2” dual plenum spacer was a very noticeable performance improvement. No supportive tuning. Just parts swapping.

1” open very crisp off idle, low end was ok but noticeably lacking once you got to the top end and how hard it pulled. Really light weight design spacer. Negligible color difference in plugs.
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Fun fact, this spacer is from this same intake when I purchased my 77. 1” 4 hole, same crisp off idle, way more consistent spectrum of powah! Haven’t checked plug color.
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Wall of garage art. ‘70 Boss 302 valve covers
:smokin:
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No block heater and I’ve successfully started in the single digits. Tuning advancements are noticed since a year ago being thrown to the sharks (no fair weather tuning)
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Capped off the end of my heat riser with metal tape. Draws air solely from the 1-3/4” ports. Also plugged up cold draft sources on filter housing. Noticeably warmer but not enough to open the switch for cold air intake. Hard to believe an engine can run on 2” intake source of air. Without using a gopro I’d say the cold air flapper does not open at WFO. Vacuum tool activates motor @ 3”
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Had to make a low pro vent tube for the OE filter housing
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Duraspark fun begins
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Random picture to troll the oiling mods on FB. You can’t remove the bypass line. You’ll have no pressure! It’s all same/same. I only notice approximately 5psi less on full cold start. 65 vs 70. Same 15 psi idle @ 100% operating temps. What’s better it how quickly it builds oil pressure on start up.
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DS module and coil mounting
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Mimicking this bump out on the fender support for the bracketry. Wanted to utilize the pattern of existing holes but duraspark holes wouldn’t clear the dimple die.
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Paper template to find holes. Going to move the e-core coil up to this bracket.
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MSD vibration isolators
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Might have this ignition retrofit finished next week. Biggest hold up is coil decision. Stock canister or can the summit coil be reused (with or without additional resistor??) Lessons in primary and secondary resistance……
 
are both coils the appropriate turn ratio for the DS?

The resistor limits current into the coil. Why?
because the coil typically saturates magnetically below it's short circuit current rating. There is some current value at which more current/flux won't provide a benefit while running.
Then why does the resistor get bypassed during starting?
Simplest method to get more energy in non-running condition.
 
Turn ratio hasn’t come up in my research. I’m aware of the spec when shopping coils but haven’t read in context what I need for DS.

Not sure if I follow your rhetoric…full spice is nice to chooch the noise machine but long duration of full spice will cheech the sparkler devices.

At some point the threshold is crossed where more spark is ineffective or unnecessary. All the xx,xxx volts aren’t needed for “normal” combustion pressures etc.

Coil in use
Summit Racing SUM-850617 Summit Racing™ High-Output Ignition Coils | Summit Racing
 
WiscoF100 said:
Turn ratio hasn’t come up in my research. I’m aware of the spec when shopping coils but haven’t read in context what I need for DS.

Not sure if I follow your rhetoric…full spice is nice to chooch the noise machine but long duration of full spice will cheech the sparkler devices.

At some point the threshold is crossed where more spark is ineffective or unnecessary. All the xx,xxx volts aren’t needed for “normal” combustion pressures etc.

Coil in use
Summit Racing SUM-850617 Summit Racing™ High-Output Ignition Coils | Summit Racing
Click to expand...
additionallly, going full voltage during cranking offsets the many times the battery voltage drops low during cranking, helps keep the ignition firing
 
The summit coil listed is 72:1 turns. Claims universal. it will work.
Similar to the summit 72 turn coil I use with a CD/MSD box on my 351, listed as 'CD' type

55000 V / 72 = 763 V primary voltage needed to get 55,000 volts out secondary. (CD box is 500 600 V)

The other flavors of hot 12V coils are more like 100 to 120 turns. MSD, pretronix.
 
The coil life is greatly extended by limiting heat, done by limiting current. The coil has current through it almost all the time, only not when spark is generated.

Just some thoughts on resistor or not.
 
So limiting current even to a 12v coil is beneficial?

I think the best route is a stock coil for now. The new harness wouldn’t have to be chopped up and there’s no question regarding reliability. The “hot rod factor” of moving my ecore coil to the new bracket etc is cool but I don’t need to roll the dice.
 
Yes. I'd say only old school 12V coils use an R. Should have the resistor they were designed for.

There is no external current limit resistor on cap discharge or most any modern ignition system. The coils can be designed to not need them, have an internal resistor, or driven with a current limited supply.

Ignoring magnetic saturation and wiring losses, from a DC standpoint;
Summit coil has primary R of 0.24 ohms. at 12 V
I = V/R = 12/0.25 = 50 Amps !
P = I*I*R = 600 watts Hot, not going to last long....

If you add 2 ohms series R
I = 5 amps
P = 55 watts

The ignition system uses a DC pulse, as only AC signals can pass through a transformer, which is what a 'ignition coil' really is. The transformer matches the impedance mismatch from low impedance (12V battery) to really high (spark plug gap).
 
WiscoF100 said:
So limiting current even to a 12v coil is beneficial?

I think the best route is a stock coil for now. The new harness wouldn’t have to be chopped up and there’s no question regarding reliability. The “hot rod factor” of moving my ecore coil to the new bracket etc is cool but I don’t need to roll the dice.
Click to expand...
if the coil is designed for 12v, don't limit it. let it run at 12v+, to whatever the alternator is putting out.

as said above, it's really just the older externally resisted coils that it matters. The oil bath isn't the best thing for dealing with the heat the old windings make. newer style stuff doesn't have that concern (well, unless you have a new old style coil intended to run on lower than 12v)
 
rattle_snake said:
Yes. I'd say only old school 12V coils use an R. Should have the resistor they were designed for.

There is no external current limit resistor on cap discharge or most any modern ignition system. The coils can be designed to not need them, have an internal resistor, or driven with a current limited supply.

Ignoring magnetic saturation and wiring losses, from a DC standpoint;
Summit coil has primary R of 0.24 ohms. at 12 V
I = V/R = 12/0.25 = 50 Amps !
P = I*I*R = 600 watts Hot, not going to last long....

If you add 2 ohms series R
I = 5 amps
P = 55 watts

The ignition system uses a DC pulse, as only AC signals can pass through a transformer, which is what a 'ignition coil' really is. The transformer matches the impedance mismatch from low impedance (12V battery) to really high (spark plug gap).
Click to expand...
Thanks for the detailed explanation. I don’t know the definition of I and P in your equations though. And if I understand correctly, your example says 12v will cook the coil? (600watts) Pretty sure it was never more than luke warm as is but controlled from a CD box. Some argue these controllers aren’t constant voltage to the coil. Idk I’m just lost at sea and trying to make sense of a “new to me” ignition system. Always been a full aftermarket (XYZ brands) or points. Never approached DS, much less introducing a “hot” coil into the system.

Reading through many decades of DS tech, folks say 1.5ohm resistance is carry-over technology from 6v coils (or that 12v coils were really 6v leftovers etc. hence 6-8v with resistor)

Some argue that the higher current load with 12v applied to the coil is shared upon the breakerless ignition module. I don’t know if I agree because the relation between the module and the distributor is simply a breaker communication. On off on off on off. The module is telling the coil to fire, dwell etc
Provience said:
if the coil is designed for 12v, don't limit it. let it run at 12v+, to whatever the alternator is putting out.

as said above, it's really just the older externally resisted coils that it matters. The oil bath isn't the best thing for dealing with the heat the old windings make. newer style stuff doesn't have that concern (well, unless you have a new old style coil intended to run on lower than 12v)
Click to expand...
I’ll give it a shot a little further down the road. It’s also an opportunity to compare stock vs spicy. I’m buried in snow and single digit temps. I need to keep it simple.
 
WiscoF100 said:
Thanks for the detailed explanation. I don’t know the definition of I and P in your equations though. And if I understand correctly, your example says 12v will cook the coil? (600watts) Pretty sure it was never more than luke warm as is but controlled from a CD box. Some argue these controllers aren’t constant voltage to the coil. Idk I’m just lost at sea and trying to make sense of a “new to me” ignition system. Always been a full aftermarket (XYZ brands) or points. Never approached DS, much less introducing a “hot” coil into the system.

Reading through many decades of DS tech, folks say 1.5ohm resistance is carry-over technology from 6v coils (or that 12v coils were really 6v leftovers etc. hence 6-8v with resistor)

Some argue that the higher current load with 12v applied to the coil is shared upon the breakerless ignition module. I don’t know if I agree because the relation between the module and the distributor is simply a breaker communication. On off on off on off. The module is telling the coil to fire, dwell etc

I’ll give it a shot a little further down the road. It’s also an opportunity to compare stock vs spicy. I’m buried in snow and single digit temps. I need to keep it simple.
Click to expand...
I = Current (amps)
P = Power (watts)

 
The other day I had a no-start condition. Just solenoid clicks. Couple tries and it fired off. Figured the solenoid or starter was to blame. Last night when it was 2* the starter quit mid cycle followed by nothing but clicks. Used my snow scraper to beat the solenoid and starter. It worked but would grind horribly before the engine would chooch. Made it home.

Cleared the snow off today to bring it in the shop. While browsing new starters last night I discovered that my nippondenso starters have been wired incorrectly since 2005. I’ve run the battery to solenoid solenoid to starter with a jumper wire at the starter. Turns out that’s a dumb way to do it. Instead it should be battery to starter and fender solenoid to starter solenoid. Takes the heavy load off the fender solenoid. Makes sense just never thought about wiring it that way.

The problem. Jumper wire terminal nuked itself. Hopefully 12ga and matching yellow terminals will be enough?
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Wouldn’t you know? The starter performs as expected now :homer:
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Added rivnuts for solenoid mounting. So happy to have that tool now. I’ve stocked up on all the mandrels and organizer box full of inserts.
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Trimmed off the “coil” portion of the DS bracket.
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Coil mounted. Holidays, weather, road trip and sick family threw everything off. Need a solid day or two so all the wiring can be properly consolidated and routed to swap over ignitions.
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WiscoF100 said:
Added rivnuts for solenoid mounting. So happy to have that tool now. I’ve stocked up on all the mandrels and organizer box full of inserts.
Click to expand...
Nice, they are handy. As you know I'm all about rivnuts.
The starter solenoid coil is grounded through the two mounting holes. Rivnuts aren't really the best method to electrically ground something with. Yes they work fine, and better if the hole surfaces front and back are ground to fresh metal. The current isn't that high (but is required to use at least 12 ga wire to starter solenoid), nor does any voltage offset matter.

But from an electrical standpoint they add more layers of stuff between the contact points. Not sure what the electrical conductivity of the rivnut plating is, but its not optimized for contact resistance, its for corrosion. Assuming they use yellow zinc chromate, it's meh and get worse with age. Salts and oxides in general are are poor conductors. Most things don't matter some do.
 
I can make a little ground jumper for it. 👍 Going to do the same for the DS box since it’s mounted on rubber isolators.

Incredible how fast the engine cranks and easily starts just by correcting the circuitry. I feel so dumb.

Also worth mentioning in my research, by connecting PMGR or Denso type starters in the old school fashion (fender solenoid carrying the load) (jumper wire at starter) the starter becomes a generator under some circumstances and will run-on. Over the last year, mostly in extreme cold, (high load) that has occurred to me several times. I blamed the starter quality or stuck bendix/cold grease. Luckily only for a brief moment and released/de-energized. Most report catastrophic failure and epic broken starters when this occurs. I surely didn’t like the angry noises mine made.
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Don't need a jumper just an aspect to consider when using them as a gnd.

No shame in finding and improving the starter wiring. That's how this hobby goes.
 
I need a vacation just to work on vehicles. No time to cut-over new ignition system or replace heads or block heater…..

Ford wouldn’t even chooch on starting fluid but partly the batteries fault for only being good for 2 start cycles.

-12* lows and Thursday-Sunday expect lows of -22* highs -8*. Just two more years just two more years. There’s enough warm weather folks in this chat, save me a spot somewhere.

I’d bet 15 minutes of this would’ve been good but it was more like 45…lit right off!
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Lake smoke topped off with some cloud seeding. They did wonderful today. My crystal blue sky has perfect cross hatch/no sun
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RAM temps can’t get where they need to. Don’t know why I’ve never done this before. Suspect block heater may be inoperative. Could’ve been bad receptacle at work (didn’t use an illuminated cord) Adding a 4a tender to this rig as well
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1 hour delayed sunrise because lake smoke
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SableDuty battery is a fat girl. Not sure if weather, battery tender or inoperative condition caused this. Haven’t driven in a year because dumb old truck is more gooder. Has fuel leak, cooling fans won’t shut off and secondary cooling fan blade came off the motor shaft.
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Please let the Jeep survive for the family🙏
 
How’re you supposed to tell a bad one from a good one? Old heater has evidence of touching cylinder wall. Shiny copper.
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