Holley 22XX Series Carb Stuff

Ron, after doing the adjustments with the tach meter and vac gauge , I still have a little hesitation with truck in gear [auto tranny] . I think after further in spection the accelerator pump rod has been shade treed too many times . I have the rod in slot 2 at this time . truck only stumbles when you have lite presure on the pedal . when you step on it it seems fine im thinkin its fine tuning on the pump but not real sure . here;s my numbers after tuning 20 in.vac 10 degrees timing 30 on the dwell at 700 rpms in neutral any thoughts would be appreciated
 
Move the accel pump actuator rod to the slot that will allow a pump shot "quicker/sooner". These superpig rigs must have a real healthy pump shot off idle to make 'em launch.

And ya May need to "straighten" the bend in the rod also, do whatever ya need to do to make it launch clean. Pay no attention to specs. After doing that and testing if it's still not quite like ya want it, then richen the idle mixtures ever so slightly and try again.

The numbers look real good...especially the vacuum! I'm impressed!
 
Toepainter, you might try a different slot theres nothing magic about the slot #, I know I was not able to set the pump travel according to spec. I had to play with it until I got the most travel on the accel pump and maybe just the slightest pressure on the pump at idle meaning, make sure there is no space or play with the pump rod/pump. In other words the slightest movement on the accel moves the pump. I am sure michael will have the answer.
The light pressure on the pedal/stumble May not be the pump. Does the truck ping under load? 10* might be a touch to much.
Does this stumble happen in gear or neutral? The accel pump works when you are depressing the pedal not when it is held in one place. I am sure you are at temp when you are tuning? Choke all the way open? I forgot to check mine after I rebuilt my carb, the choke was staying shut a little too long.
What do you thing michael?
 
Thanks for the quick reply guys. Yea I thought the numbers were good too. No pinging tried the lower setting on the timing but she seems to be sluggish at any lower advance the motor is real tight. 150 to 158 lbs per cylinder new intake and valley gaskets. Will try another slot and I'll just keep playin with her. Its way better than it used to be. I dont want to change to a 2300, even though they are easier to work with but the challenge makes it worth it . Whats so good is being the guy with the stone age Scout that seems to be the recovery unit for all the guys who talk smack on the mountain.I just tell em I'll see you on the way off probably chained to my rear end ha ha ha
 
Up to about 3000ft., 304 or 345 seems to like up to 12* btdc base timing if the distributor is in first class condition with little runout on the advance unit and limited endplay on the drive end. That's on "regular" grade fuel, these are low compression motors and I refuse to run anything other than regular.

A distributor with excessive endplay allows timing to go to hell throughout the rpm range! Impossible to hold a "tight" timing curve from idle to 2300rpm at which point all advance is "in". If ya use a "dialback" timing light, ya can easily see a sloppee distributor! We'll be discussing that soon over in the ignition forum.

So I'd power time it up to the point of detonation and then just back off a touch until detonation is eliminated. Then shoot it and see whatcha got for reference.

As ya go up in altitude (say over 3kft.), then it can tolerate more advance but it's not worth scruuin' with unless ya spend all yore time or live up there.

And as mentioned, make sure the choke pulls off all the way and is held "off" by the vacuum pull-off diaphragm. To adjust that, simply pinch that link where it makes the deep "u" bend, to create more pull on the choke actuator. Of course, that assumes your choke pull-off unit is working properly and will hold a vacuum!
 
Interesting michael I was not aware the timing was affected with alltiude. I always thought it was just the jets in the carb. Out here in the flatlands just never had to deal with it. Learned something new.
 
Ok guys carb is starting to give me the want to throw it as far as possible in favor of a single barrel 1951 model zenith. Lol went wheeling this weekend, pretty much got rid of the stumble off idle. Workin with the accel pump has really helped. The specs are bs. As you said. Now the issue seems to be heat transfer and possibly float level. Put her on a hill and she wants to flood out and die. My spec sheet calls for 3/16 float level should I try 1/2 or greater . Also sometimes getting the infamous Holley pop .which in turn blows off the vac caps. I made sure the power valve actuator was clean ,polished and worked freely. Any suggestions ? Thanks brad
 
Brad, it sound like your making progress. This one is probably out of my leage, I will have to let michael answer this prob. Just how steep was the hill? There is a mod for an off road 1904. But I am not sure this is a carb problem. I did follow the specs for float settings but I have not done that much off roading, yet. Maybe the needle valve or float is sticking.
Sorry not much help.
 
Sorry I missed this boyz...I been actually doin' meaningful work around here...got rookies enrolled at binder u. That take much supervison, we're trying to finish off installation of a highly modded after market 30 gallon fuel tank tonite. Tanks' under pressure test right now.

Lower the float to whatever makes it not drool liquid down the throats. Again, scruu tha specs, make it work!

Don't know about any "Holley pop", if it's spittin' back through the intake, then a valve(s) hangin' open or the timing is somewhat retarded. Again...scruu tha timing light, advance it until ya get detonation under load, then back the timing down a touch until it goes away.

A 22xx won't "blow" the economizer/power valve if it spits back through the intake like really old Holley modulars might. If the pv was blown (or loose), then extreme richness would be experienced as the power valve is equivalent to 5>8 steps Rich over the size of the main jets. And this richness could not be "adjusted out" with the idle mixture screws.

Is there any lifter noise that won't go away? If so, that could be a valve that is trying to stick from lack of lubrication...that comes on very slowly over time. The lifter rattle is a key to that if present, valve is sticking in guide (trying to seize) and/or a rocker arm is partially seizing.

As in some of the other threads you've no doubt now read, do a visual of the carb fuel/air delivery by looking right down the bores while opening the throttle slowly, were a face shield for eye protection! Watch for "globs" of liquid fuel forming/drooling, and of course, look for a heavy, solid accel pump discharge "shot" each time the throttle is whacked.

Do you have the oem-installed "heat dam" base gasket between the manifold flange and the carb? The one with the "projection" under the fuel bowl, not just the thick base gasket?? That is a fel-pro supply part, originally spec'd for the Scout II with this carb, fel-pro # 60677. And did your carb kit include the "thick" throttle body-to-main body gasket? That is also a heat insulator, not just a gasket.
 
Regarding the "altitude" thang...and we're talkin' carburetors here...not fuel injection...

If you have a carb jetted ragged edge for your "normal" operational elevation, and you are running the ignition system at maximum advance for the fuel grade used (in my case, always "regular" whatever that means at that point in time), then occasional detonation (ping) under heavy load can be experienced. And that would be with a distributor that has been "curved" for max performance, not a woreout oem distributor.

That basically describes tuning one of these motors for max power/burn efficiency and charge density (non-heated intake manifold) and has nothing to do with "factory spec", "emissions spec", etc.

Then without changing anything except the operational altitude...the rule of thumb for non-forced induction, gasoline-fueled engines is for a 3% power drop for every 1,000ft. Increase in elevation. And likewise, that represents an approximate 3% in air/fuel ratio "richness" over the same range. Again, this is rule of thumb/seat of pants stuff ya can take to the bank.

Most folks don't wanna re-jet a carb unless they May be staying at a different elevation for an extended period of time. Some improvement in drivability May be experienced by tweeking the idle mixtures though, but then when the elevation decreases, another adjustment will be needed.

The increased richness due to the lower air density at altitude will actually tend to "cool" the combustion charge, allowing a slight increase in base timing without going into detonation. It serves to "mask" detonation in a roundabout fashion.

Adding an adjustable timing control to an add-on capacitive discharge "box" such as an msd 6 series, or the mallory 6 series allows the base timing to be electronically controlled from a dash-mount potentiometer control specifically mated to the box being used. The result is a driver May vary the ignition base timing while under way, based upon fuel octane and carb jetting, thus allowing a possible increase in performance which May somewhat offset the lack of performance created because of the operational altitude.

This is not for everyone to diddle with, only for folks that like to scruu with stuff that ain't broke! But especially helpful when using old iron for towing duty in mountainous terrain. My typical pattern of usage throughout the years takes me with and without the 6500lb. Trailer from sea level/1100ft. To 10,500ft. (shophouse elevation is only 670ft.), at ambients of 5*f>95*f on many days. My engine setup runs well from sea level to about 7200ft. Before it really starts ta suk! An adjustable timing control May really improve that sitch...my only concern in this regard is fuel economy when towing at max capacity. 0.5mpg up or down really affects my budget onna 10,000 mile trip. And in just local backcountry rides we can go up to 5300ft. In under 20 minutes.

Tweeking the knob while driving by the tach and vacuum gauge soon becomes routine when you are trying to squeeze out the last drop from a dollar! Most especially say on a looonnnggg continuous uphill pull such as baker grade on I-15 'tween lalaland and hellvegas, or 'tween kingman, az and flagstaff, az eastbound on I-40. Roswell, nm to santa rosa, nm is another killer pull!
 
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Thanks michael, will set the float lower and do som timing work. Going wheeling tonite. So we'll find out ,thanks for the advice again.
 
Ok, moved the timing to 13dg and dropped the float to 3/8 inch from 3/16, reset mix screws and idle. Runs good, great acceleration with no detonation. Seems to have alot better seat of the pants feel. Numbers are as follows

13 degrees timing sv 304a
21in vac
30 dwell
700 rpms 670 in gear
acel pump in slot 2 with rod adjusted to get full pump shot

ran truck about 60miles last night, plugs seem a little lite on color. Carb has 52 jets thinking of stepping up to 54. This May help with power and driveability.
Just gonna keep on fixin what aint broke ,hopin to get some better results.
 
Also, would love to get rid of the factory choker on top of the carb. Anyone got any pics of a home grown air intake? We do a lot of muddin and rocks down here in georgia so a snorkel type would be great any advice and pics would be great.
 
Even better results!!!!!

What'd I tell ya! The 266/304 motors luv timing! And of course, doin' all this has nothing to do with "smog specs"!! Even though if ya ran a idle-only three gas smog check I bet it will actually be better numbers than right off the assembly line.

When ya hit the lottery, swappin' ona centerhung 2300 list 0-7448 will really make it sit up and beg! And then ya can put any homebrew snorkel on it ya can rig up.

See this thread for "maybe" a boneyard workaround for a different air cleaner for a 2210/2245:

http://www.forums.IHPartsAmerica.com/ignition-tech/825-dui-install-345-stock-2bbl.html

The single snorkel intake plenum from specter products (I use the dual version) will allow any kinda plumbing ya can dream up.

The oem air cleaner systems on all "dry"-type IH applications were a "silenced" design and greatly strangle these motors. Just putting a free-breathing air intake system on 'em will give a seat-of-the-pants (and audible!) kick! And enough increase in air available (depending upon throttle plate angle/load) to warrant at least two steps richer in main jet size using a Holley carb of any design.
 
Gonna look around for a old air box got a connection on old cars at a friends grandads back yard picture that old cars in a back yard in georgia. Well it could be his front yard not real sure where the front door to the trailer is . Lol yea air flow seems to help these mills. Lost a big vac plug last weekend after a intake pop. When you touched the throttle it was alive!!!. On switchin to a 2300 they are hard to find here unless you buy new. [to many dirt track cars]. Also do I need the 350 or 500 cfm. Advance auto has the factory reman 2300 for 136.00 plus core. But im scared it will be junk due to the fact they bead blast their cores to clean them.
If all else fails, I found a 79 midas edition with a 345 thermo quad Scout I might do an engine swap.
 
The Holley list 0-7448 is the only carb ya want if you are looking at a great upgrade. It can have the electric choke added.

The list 0-4412 (500cfm unit) is not suitable at all for any IH motor. It cannot have an electric choke conversion added.

I do have a fresh 4412 right now (actually have three of 'em) that will go on my rpt-manifolded (is that a word?) on my 392, but only after I complete all the ignition systems testing. It will be used as a comparison unit for performance/milage and will sit on an adapter, which is not the best way but is the only practical way for this experiment.

The 2300 conversion is what is under discussion in this thread along with a pic of the kit that ihon offers and will soon show up in the online store. Everything is included except an air cleaner since that will vary greatly depending upon exactly how your rig is set up!

http://www.forums.IHPartsAmerica.com/carb-tech/739-rebuilding-2300-list-2977-carb.html

The only "reman" version of the 7448 to use is a Holley-reconditioned unit. We're trying to get a line on those onna regular basis from Holley, about $100 less, but the supply is very erratic and not something we can depend upon.
 
Hot damn !!!!! Went wheeling today. Put the old girl thru some tough paces. Lots of hill climbing and decents. Some serious mud too. Carb is really acting great. No hesitation , cold or hot, no more dying on hills and when you get her bound up in some serious shit she gets madder than hell and just starts diggin. Thanks for the advice !!!!! These little tweaks got her woke up!!!!. Now I've just got to get a borgeson shaft to get rid of that pesky rag joint. They have a mind of their own with no steering. Lol let me know if these are available from ihon and a price this is a must she's been upside down due to this already and it almost went today. Once again thanks for the help. Brad
 
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