Ignition

michael mayben said:
if the "new" carb is a list 7448 Holley, for your current location/altitude the setup I'd use is:

1) adjust float/fuel level so that it's 1/32" (nominal) below the bottom of the thread on the sight hole in the side of the bowl...do this first.

2) I'd run a #65 power valve. That should be what is in it if the carb was a new one out of the box.

3) original main jets would be #61 from the factory. I'd start off with #56 or #57.

4) out of the box, that carb should have #85 power valve which is ok, but a #45 would be better.

5) electric choke cap should be set one tick Mark to the "Rich" direction form the exact middle position (long tick Mark).

All this tuning setup is based upon the use of autolite #85 (or #303) spark plugs or equivalent heat range. Don't change heat range or all the tuning stuff goes to hell!
Click to expand...

I will start with this shortly first question where is the p/n located on the carb so I can verify what equipment I do have I will run with the above but will probably let a shop do the work as I am more of an electrical guy than a Holley carb guy (too many small parts and short fat fingers) I will shift to the carb section after this as I have to read up on what a power valve is and get more familiar with the jetting needle sizes and all that this engine is supposed to be rebuilt and bored .040 over so I will need to submit what I have been told (sold) I have I am also new to automatic transmissions as all the trucks I have are standard except the spirit of 76' which has not run since I was about 5 (all numbers match though :) )
 
Our knowledge base for the Holley carbs (in this case the 2300 deign series) is contained in this thread:

http://www.forums.IHPartsAmerica.com/carb-tech/512-Holley-23xx-series-modular-carb-stuff.html

And in the carb tech sub-forum, you will find many threads regarding the subject of tuning these carbs, especially for higher altitude operation.

The "list" number is Holley's methodology for identifying each distinct calibration of any given design series unit. The number is stamped on the front of the airhorn when looking at the carb from fuel bowl end, upper right hand corner. Sometimes the word "list" is stamped in, sometimes not.
 
So new problem. Started fine a little miss and was missing off throttle on the way to work. Started leaving work evened out a little and then started stuttering almost to the apt got out pulled the power filter started up stuttered to the apt started evening out when off throttle in the parking lot before I left was goosing the top of the carb to see if I had some trash throttled her up and she revved but uneven and smelled a lot of gas like it wasn't burning all the day before it ran perfect. I changed the fuel filter as there was a lot of rust in it (bought spares) but with all the ignition problems I'm not sure where to start she starts she idles she misses a little at idle something has changed overnight and I need some help any thoughts/ideas would be mighty appreciated never have had this many issues with keeping a Scout running
 
If you are seeing crap in the fuel filter, then the tank has the typical rot disease which is very common on this stuff.

My suggestion is that "stuff" has also now gone through the filter (most of those have a micron rating of around 50) and contaminated the inlet needle seat assembly inside the carb. When you pull the plug out of the sight hole on the side of the bowl to look at fuel level, gas will pour out. These carbs are extremely sensitive to correct fuel level which should always be verified/adjusted once a new carb or fresh rebuilt is installed and running.

Fuel level with the engine running at idle should be just below the bottom of the threads in the sight hole.
 
So with the symptoms described are you thinking fuel contamination at the carb? With all the ignition problems it's hard to not want to start there. So if I pull the screw by th sight glass at idle should fuel come out or should it stay steady? If fuel comes out does that mean I need to drop the bowl or do I need to pull the "new" carb all the way down?
 
scoutpappa said:
so with the symptoms described are you thinking fuel contamination at the carb? With all the ignition problems it's hard to not want to start there. So if I pull the screw by th sight glass at idle should fuel come out or should it stay steady? If fuel comes out does that mean I need to drop the bowl or do I need to pull the "new" carb all the way down?
Click to expand...

If trash went through the filter, then it contaminates the needle/seat cartridge. As fuel continues to flow though that point, it will normally "self-flush and the debris will fall to the bottom of the fuel bowl and metering black and simply lay there...looks like extremely fine rusty power (which is what it is). Only if it should build up to the point it begins to block one or both main jest will create a drivability issue. Larger chunks/flakes of rust will lodge in the needle/seat cartridge and create a major flooding issue with raw fuel running right down the throats.

If when you remove the sight hole plug fuel runs out, then the fuel level is too high, that also creates the internal flooding issue. Fuel level is adjusted with the engine running at idle...and that is based upon the fuel pressure being correct and within the nominal 4>6psi range. The float and needle seat can handle that, any greater pressure will force the needle off it's seat and flooding will occur. Those carbs are rated at a standard inlet fuel pressure of 5.5psi, that is within tolerance for the oem mechanical fuel pump.

Fuel level is adjusted by barely loosening the slotted lock screw on top of the bowl, then using a box end wrench to carefully raise or lower the seat by gently turning the adjusting nut, then locking down the screw for verification. Put a rag under the hole in the side of the fuel bowl so that spilled fuel won't hit the hot exhaust crossover on the intake manifold and ignite it!
 
Back to ignition failure. Re-built the carb today was not in real bad shape but discovered that I have a list 4412-3 500 cfm race application carb. The only thing I can think of now is that when I ran the accel mdule with out the ballast resistor I screwed her up. I will order the mallory module (more expensive) and keep the wiring per mallory as I have it now. Try that and see. Are there any other interlocks that could cause a problem. When it died today after the carb rebuild run in it didn't want to turn over for a second. Shifted it from park to drive back to park and it turned over. Is it possible the safety switch could be part of the problem and should I replace it or jump it out and not worry about it (except maybe turning the motor over in gear) also the float valve was sticky so the rebuild was worth the while couldn't get any smaller jets and couldn't get a smaller power valve did get a contact to maybe get the parts needed as well as smaller squirters the resident Holley expert said that the #32s' stock in that carb are way to big
 
The 4412 is exactly the wrong 2300 carb for your engine application! It's way too fat in all circuits and it's just not possible to tune it "down". It's all about the passages that are machined into the main body and the metering block.

I've spent hundreds of hours on that carb trying to make it work nicely, it simply is wrong, even at sea level.

The shooter in it is a #31. Changing that to the next lower flow part (#25) will do nothing and neither will changing out the accel pump cam to a different profile, the accel pump system is not the issue with the 4412, it's simply wrong for the application. And internally (and externally) it's somewhat "different" as compared to the list 7448 (350cfm) version, they are apples and oranges! We will not sell a list 4412 knowingly to any ihon customer for use on a 304/345.

Yes, an nss switch can be problematic after 30+ years! And so can the relay that it works through! Even more likely, the pigtail connector that attaches to the the three pin nss switch on the trans. The horn relay and the nss relay are identical and interchangeable. There is information regarding servicing this stuff in the transmission sub-forum if ya search.
 
Wanted to sit down at work and ask all this but didn't get the opportunity. So here we go
have you ever heard of so many problems with a unilite dist?
Should I replace the module this last time with the mallory rplcmnt?
Do you know anyone that would want a brand new shiny Holley 500cfm "race" carb or would like to trade for a regular 350 cfm stock carb (prefably with electric choke)
can the safety switch on the transmission cause the ignition to to stop firing?
 
Summit was quick to replace the module. Wonder what that means. New module on the way next week when they re-stock. One positive.
 
scoutpappa said:
wanted to sit down at work and ask all this but didn't get the opportunity. So here we go
have you ever heard of so many problems with a unilite dist?
Should I replace the module this last time with the mallory rplcmnt?
Do you know anyone that would want a brand new shiny Holley 500cfm "race" carb or would like to trade for a regular 350 cfm stock carb (prefably with electric choke)
can the safety switch on the transmission cause the ignition to to stop firing?
Click to expand...

The nss system (neutral safety system or switch) does not interact with the ignition system in any manner unless someone has badly botched some wiring around! In original form it only interacts to prevent starter operation if the transmission control lever on the shift shaft of the tf 727 is any position other than park or neutral.

As we discussed in the beginning, if the mallory unilite distributor is used only with an oem-type coil of the correct primary resistance factor, then it must use the proper ballast resistor added to the oem primary wiring to the coil. That is specific only to the unilite distributor trigger system and is the controlling factor to proper unilite module operation and life expectancy. This mallory system is totally unlike any other oem or aftermarket distributor/electronic trigger system.

My opinion...the previous owner or whoever originally installed the unilite distributor obviously did not follow the very simple instructions! This is fairly common, and the unilite system has received harsh criticism over the last 20+ years in regards to failure which can always be traced to incorrect installation. Every electronic device has it's own unique methodology for keeping it troublefree, this stuff functions perfectly if installed correctly.

I know nothing abiout the "accel"-version of a replacement unilite module. However...as you can see when leafing through the current prestolite/mr.gasket/accel/mallory catalog pages, many of the mallory components are now being rebranded for marketing at a "popular" price point under the accel label. They are not alone...this is the trend amongst all aftermarket parts manufacturers/distributors today since their business is in the shitter and everyone is attempting to sell on "price" rather than quality.

As for the Holley 4412...I have at least four of those right now! Most came from folks who acquired 'em off egay after "assuming" they were correct for a 304/345, they either had smoke blowed up their butt or believed the hype pimped by summit and jegs. Those are astounding carbs when used on the correct engine app such as a 450+hp sbc inna circle track "class" application...but they ain't worth crap for an ihc-produced truck motor that struggles to see 4000rpm. The classifieds are full of 4412 offerings, but they move fast since the dirt-track dudes want a slew of 'em , they all know how to build cheaters out of 'em and as such they are in demand in that arena.

You cannot buy an out-of-the-box Holley list 7448 2300 carb with electric choke which is perfect for your application as you have seen over and over in these posts. The proper Holley electric choke kit must be installed after removing the manual choke actuation components. And the electric choke kit for the 4412 is not the same animal as the similar item used on the 7448! It cannot be "adapted". You must pay attention to part numbers when dealing with this stuff. The Holley website gives complete information in this regard, the summit and jegs crap just wants to push parts off on unknowledgeable customers and then they let their "customer service" department deal with the fallout!
 
The oem coil primary resistance is between 1.4 and 1.8ohms for an ihc sv engine (v8). That also works "ok" for a six cylinder application (IH "diamond" series 12volt, and the amc 232/258). For the I-4 (four cylinder) engine, we want a coil with a primary resistance of 2.4>3.0ohms. And...there is no difference in the coil mused with breaker points vs. Any of the electronic ignition systems that ihc also used (prestolite, Holley, and delco).

Secondary resistance of a conventional "bobbin"-type coil insulated with oil or pitch (or epoxy) is not real critical and is always going to be a factor of the "turn ratio" of the particular design and the gauge number of the wire used in the forming of the secondary winding. But an average secondary resistance for diagnosis purposes would be in the range of 5k>12kohms. That is for a battery ignition coil (not a magneto type).

All this data is for the coil only. Do not confuse the "resistance" used in the primary feed to the coil "run" circuit. And this information is only for an ihc-produced vehicle, along with virtually all GM, chrysler, and amc-produced systems. For the most part, Ford did not use a "ballasted" feed to the coil for engine "run". They used a coil with a higher primary resistance factor and did not incorporate a "by-pass" circuit used for starting purposes only. There for...no conventional canister coil for a Ford breaker point or some electronic ignition systems is suitable whatsoever for use in any IH application.

However..the evolved Ford "eec"-series electronic ignition variations started using the "e"-core design coil (those were developed by the motorcycle, marine, and industrial engine world way before the stuff was ever used in domestic automobile/truck systems). This would be such as the Ford "tfi" coil, etc. Those are ok items (though I think lacking in quality and durability, I personally would not use that stuff) that happen to have a primary resistance factor in some versions (not all) that is suitable to use directly with ihc breaker points, a mag trigger conversion, or with a pertronix (hall effect) conversion.

I totally enjoy working with this ignition stuff, my favorite part of scruuin' with junkiron nowadays! And it's a real challenge to work through all these typical po-induced problems that you see posted around here almost daily! While they can all be kinda different in the way the stuff was jury-rigged (such as using a coat hanger for a wire run to a sparkplug), once all the virus stuff is eliminated, there is no single area on these rigs that will do more for the enjoyment of operation than having a functional/reliable ignition system!

And soon...I'll be posting some additional information to our "performance" ignition system stickee. Hopefully...in the next few months we'll also see an IH sv motor running a roots blower and being lit off by a mallory unilite distributor and cd box...for street use!
 
I hear you man. It only sucks when you are on this end. Accel 8140 super stock = primary resistance of 1.2 ohms. I'm in the hole on another part. What coil would you suggest for a replacement as I only want to do this once more.
 
scoutpappa said:
I hear you man. It only sucks when you are on this end. Accel 8140 super stock = primary resistance of 1.2 ohms. I'm in the hole on another part. What coil would you suggest for a replacement as I only want to do this once more.
Click to expand...

I have several of the accel "super stock" coils myself, all of which exhibit oil leakage from the secondary tower down inside where you see the screw slot. This is a common failure on all oil-filled canister coils I've used from pertronix, msd, and accel. I've never used/purchased a mallory canister coil so I can't comment on those. The accel coil spec'd primary resistance is 1.4 ohms which is a bit under the typical resistance factor found in an aftermarket replacement "oem" canister coil.

In my personal work now for my own systems, I only use some form of an "e" core coil, even for an oem replacement. Whether it's potted inside some sort of outer shell or manufactured in an "open" form doesn't matter to me. What does matter is that it has the proper primary resistance factor going in.

All the common aftermarket "brands" offer "e" core coils of some sort....in many different resistance factors for many different ignition system "systems". Some are suitable for a stock replacement coil. Most are only suitable for use with either an add-on capacitive discharge ignition box or spec'd for a replacement for use with only a delco hei amplifier, Ford eec amplifier, or older chrysler electronic ignition amplifier.

When doing ignition system upgrades, we must look at the total package as a system, ya can't just toss components at an engine based upon smokeblow from summit and jegs! System means everything from the initial wiring from the ignition switch, through matching the components chosen, through chosing an adequate mounting location, and then integrating whatever distributor is used with proper wiring and matching. Then comes the secondary cabling and sparkplugs.

To simplify (but I'm in no way endorsing one product over another)...an "e" core coil suitable for use with either a stock ihc-produced breaker point ignition distributor, or either a prestolite or Holley electronic ignition system would be mallory promaster "e", p/n 30450. That same coil will also work well with the mallory unilite distributor with no external add-on cd box.
 
Aha. A part number (regardless of brand promotion) I will look locally and if not order the part online. The replacement optical trigger will not be here till the 12th. Gives me time to get the coil. I will be looking at carb replacement soon and as there are dirt tracks here maybe I can dump the "race" carb.
 
Street and strip performance for mallory unilite and magnetic breakerless distributors and conversion kits. Delivers optimum performance when used with these mallory ignition products: unilite distributor, magnetic breakerless distributor, or mallory electronic ignition conversion kits. Easy to install - connects directly to 12 volts wire with no ballast resistor required. Effective to 6500 rpm when used with a mallory unilite or magnetic breakerless distributor (depending on engine combination). Do not use with mallory hyfire electronic ignition control or any other high energy, inductive storage or capacitive discharge ignition system.
Model number: 30450

you must select an option


note: the purpose of an ignition ballast resistor between the ignition switch (12v) and the ignition coil positive
terminal is to restrict current flow through the ignition coil. Failure to use an ignition ballast resistor will
eventually destroy the ignition module.
Exception: if your vehicle is equipped with a hyfire® electronic ignition control or similar aftermarket ignition
control, use the wiring procedures stated in the instructions included with the ignition control.
To prevent false triggering and possible premature ignition failure, you must use suppression type (carbon core,
spiral core, or radio suppression core) spark plug wire.
Do not use solid core (copper core or stainless steel core) spark plug wire with any electronic
ignition system.

Which is the right option? If I buy the coil I seem to end up in the same situation as what I had before. I'm confused
 
The marketing information in the mallory catalog is an attempt to cover all possible applications and types of ignition /distributor trigger systems. As such it only adds to the confusion. Whether or not a resistor is used is entirely dependent upon the entire system.

This type of inadequate marketing explanation is exactly why mallory, msd, accel, etc. Have a huge knowledge base of customer questions asked repeatedly over and over and over! They simply do not explain the details of this stuff in an adequate fashion and due to catalog description limitations, they simply don't have room to explain this stuff.

The mallory 30450 coil is exactly the same primary resistance as any oem or aftermarket replacement coil for the oem item. Therefore, it gets wired exactly the same as a stock coil in a stock ignition system, in that respect it's just a replacement coil. That is why I recommended that particular coil, it will work just fine with either the unilite module or breaker points. It is not the right choice to use with any other form of amplified ignition add-on systems such as the hyfire series cd stuff, those use the super-low primary resistance coils which are a proper match.

But...your mallory unilite is a special case! It cannot be thought of as a simple "replacement" for an oem distributor, it's light cell trigger has totally different electrical requirements as compared to a breaker point set, a magnetic trigger, or a hall effect trigger. So...it requires the use of the ballast resistor as previously noted. But...the ballast resistor is not wired into the system in the same manner nor does it serve the same electrical purpose as when that coil is used with breaker points.

Follow the wiring diagram in the unilite distributor instructions exactly. The drawing in those instructions is simply representative of "some" coils but no one exact coil. And...that instruction/drawing is only for use with the unilite distributor...no other! It is not the same as the "stock" hookup using a "stock" distributor at all!
 
Talk about making it confusing. And I got all that from the mallory website. In the end when I get the new module I will bring the red wire from the module ckt to the "high" side of the ballast resistor with the switched b+. I'll bring a wire over to the coil from the "low" side of the resistor to the positive side of the primary of the coil giving the system a variable resstance of 2.15 ohms to 3.1 ohms based on increasing resistance from heat. At this range of resistance I should be in the "safe" zone for operation but not over the threshold introducing a weak spark scenario. Even the moderators on mallory's website get the setup wrong by suggesting a coil with 1.4 ohms of resistance will make it all good.
 
Well...she runs. All wiring is exactly like the mallory schematic including bringing the module to the high side of the ballast resisitor on it's own wire. The accel 8140 was leaking (you were right and only 2 months old) so replaced in kind till my wife's not looking and then I'll order an e-coil (none in bfe wy). Really want to replace the rag joint next but still gun shy with all the ignition failures. Scared to drive her very far. The tattle tale miss is gone so I am fairly confident that the system will last this time. When I get home in October I think I will just swap the motor and trans with the motor and trans from another of my scouts'. Would prefer a bored out 345 w/ 4 barrell and unsync'd 4 speed to the automatic. Will make the decision on swapping the Dana 44s' to the 60's I have on the other Scout with some gumbo mud riding first. No rocks where I'm from but plenty of clay mud with no bottom. Hopefully I'll get the trust factor back up so I can start on the steering. Next week is home visit (sounds like I'm in prison) so will be harley week. My other babies are lacking attention.
 
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