I have a 440 rebuilt finally have it on the road ( 1964 imperial crown ) been broken in and have about 100 miles on it. not been on the freeway yet, fastest ive been is 60 MPH or so. its a complete new rebuild with MSD Box the billet dizzy from 440 source , 750 CFM street demon carb, performer 440 intake with a 1/2" spacer to make the carb fit the intake. 3/8" fuel lines new fuel pump, cleaned out the gas tank and fuel lines & new sending unit, hughes whiplash 440 cam Was degreed when installed at 0 degree, I will have to get the paper work out but, if i remember right hughes cams paperwork said set it at 12 degrees before top dead center that's where i have put it and never changed it, its bored .30 over. and i am 9.5:1 compression using 91 fuel. I had another guy mention something about making sure my choke is coming on that can make it run rich? he said it could make fuel go into the oil and ruin my rings too so that's concerning...



I had my car getting a trans leak fixed he said it is running rich, i too can smell it a little though its not overwhelming its open exhaust also getting that put on this weekend, I have not messed with the air idle Screws yet , I was wondering if running rich can cause a sputter when you go wide open throttle or when your going 3k+ rpms? i thought running lean did this not running rich? cruising around 1500-2500 rpm it seems to run fine and i have the idle like 850 ish i increased it a little for the cam, I dont have a tach so im not exact. I live in SLC utah its around 3500 feet elevation

i'm new with carbs so i have no clue how to really tune it completely right all i can hope is to get it where it runs good, but wont be to full potential think a dyno requires that? I see you use a Vacuum gauge attached to the Intake hose to set your air idle control screws what pressure do you need to be reading when doing this? ill prob try this this weekend.

Is it timed right? if 12 degrees BTDC is wrong how much it cost to just have someone that knows exactly what they are doing time it for me?

 

64 -

Does the MSD have a rev limiter?

While not impossible, a high rpm "sputter" may not be a carb problem. Usually, the engine just starts "dying".

Archer

 

No rev limiter just the standard MSD 6A box to pair with the non points system.

I checked the air idle screws they were like 3 turns out i screwed them all the way in till they barley touched then unscrewed them 1 1/2 turns each and it runs alot better, how ever it still does the spudder effect, when i get on it past half throttle and it in-gages the carb to WOT, the throttle seems like it accelerates fine soft pushing the throttle till around 3k rps then if you push it more it feels like all the power hits all at once going WOT but all it does is the spudder thing, i have the lokar throttle linkage and kick down im 99% positive its all set up right, i set it where my foot goes the the flood the carb is open all the way and i set the kick down where when wide open throttle i cant pull the kick down cable anymore then tightened it so its full engaged

i believe the factory set on the carb is 1 1/2 turns for each screw, are you ever supposed to go less than 1 1/2 turns? guy at the shop told me set it 1 1/2 turns then while its idleing turn them 1/4 turn each keep doing it till it tries to miss or idle rough then go back 1/4 turn and its set? my under standing is screwing them screws in reduce fuel and screwing them out increases fuel which in turn changes the fuel to air mixure cause the carb pulls in a set amount of air? , it does smell a little rich, how ever if i reduce the idle or reduce the fuel too much when i put it into gear it will stall, i have the stock 1800 torque converter and running 4:23 stock gears ( plan on changing these when i have the money )

 

64 -

The idle screws get set to where they need to be.
Not familiar with SD 750, but it looks a lot like the old Thermo-quads.

You might be experiencing a problem with the needle and seat, and sometimes lightly tapping it while running might solve the problem. Sorry, don't recall how to replace/clean the needle and seat on that carb.

Also make sure you're getting adequate fuel to the carb, even if the fuel line is patent, the filter can be a problem - don't ask how I know that ...

Archer

 

I would change the fuel filter

 

Just to make sure that you understand that ... any adjustments you do on idle have no impact on regular driving. The idle circuit is not doing anything as soon as the engine moves the car.


It may not always be easy to know for sure if the issue is fuel related or ignition. I have been fighting similar issues. I have a T on the fuel line just before the carburetor, and I have a hose inside the car, so that I can read the fuel pressure while driving. That way, I know for sure when I have fuel starvations.


You can replace the fuel filter as TV says, its easy and cheap. But if this problem persists, you may want to make a similar installation, so at leat you rule out fuel starvation.

 

Can this happen even if the fuel filter is new also? How much fuel pressure is there supposed to be? & on the fuel pump this being a modified engine with that cam should i have put a higher flow fuel pump on it its a stock replacement, the engine over all is pretty mild but it has the MSD ignition system and blaster 2 coil this could make it burn more efficient = more fuel burnt? making not enough fuel? it does have a rich smell to it tho so idk, i think ill try that T idea just need to know how much pressure i'm supposed to be reading

i leaned out the fuel air best i can the preset 1 1/2 turns from factory on the demon carb seem to be the working point on mine, i go any less it will try to die when i put it in gear. same if i adjust the idle at all its lowest it will go with out dying when going into gear from neutral, though in neutral sounds a little fast but from seeing other peoples videos the whipash cam has kinda a fast sounding idle on theirs in neutral.

I just thought of something, I set my TDC to 12 degrees BTDC like the cam company suggested, and broke it in that way, but i turned the dizzy at after to change the idle and i never used a timing light on it.... I don't know how to use one.. can this sputter and kinda rich smell be caused by the timing being off? i prob turned the dizzy like a quarter turn i for get which way, maybe i need to pay someone to time it for me i have done research but for some reason timing this things is very confusing to me. if this could be it what does it cost to have someone just time it for me?

 

Spend a few bucks and buy a light, not hard to use.

 

I have a light just not sure how to use it, i read you have to see what its at at idle then rev it up and see how much it changes cause it can go from like 12 to 38 or something? or do i just make sure its 12 degrees BTDC and its good? and you connect the light to the #1 spark plug and the light will only flash when #1 ignites thus only showing you the number what ever it is on the timing tape correct everything will be blurry but the number and as you turn the dizzy a diff number will be come visible and that's the timing the number you can see?

I found this http://tvmoparclub.com/files/tech/Mopar%20Timing.pdf but since i changed my dizzy and it doesn't have a Vacuum line going to it i just ignore that part and just find my idle degrees then rev to 3,000 and find that them add them together and just turn the dizzy till I am =

 

64 -

Depends on the filter. Some (like the Mr. Gasket clear one) have in and out ports that can be positioned so the "in and out" holes get blocked. Again, don't ask how I know ...

A mechanical fuel pump should be in the 5 - 7 pound range, without dropping significantly under WOT.

Since we really don't know how or how well the cam was timed, the initial and total timing need to be where they need to be and the manufacturer's spec are only a guide line.

BTW - forgot if you mentioned the vacuum advance? If your dizzy has one, if you're using it and if you have it on the correct port. Not knowing the cam specs, 10 - 12 initial and 32 - 34 total should be in the ball park. Total advance s/b all in by 3000 rpm.

Archer

 

I have no vacuum advance on my dizzy, i avoided the ugly Mr. gasket one its what i had before lmfao but its worth a check, and i had a shop build the engine and he made sure it was 0 degreed when installed and i set it to 12 degrees BTDC as hughes cams said in the paperwork, its the hughes whiplash 440 cam I bought the whole springs timing chain kit, specs below for the cam


The local Car guru guy here in town just told me he will time my car for $15 hes also tagging it for me so that seems the easiest i've had like 5 locals & businesses refer me to him in the past 3 days for things

 

Sounds like you have the total timing figured out, good work.

The carb problem, the way you described it, is the secondary air valve is too loose making it open too quickly.

Look at your carb instructions, their site or you tube to adjust, straight forward. If it persists check your float bowl level. I'm sure the AVS will straighten this thing out after you confirm your total then initial timing.

 

Your idle issue may be unsolvable. You may simply have too big a cam for the stock converter. I have a milder car on the car I am working now, and I have a big drop on idle as well, from about 900-100 down to 500 or 600 in D. My other 440 has a much smaller drop, and it also has a cam upgrade from the tiny stock cam of .425/.450, 260/260, or something like that.


If your engine continues to stall at the higher rpm's, the fuel pressure measurement while driving may be necessary to ensure your fuel pressure is sufficient. The 5-7 psi suggested sounds right, but the manual of your Demon carburetor should tell you what the fuel pressure should be. My AFB guide suggests no less than 4.5 psi.

 

I also was thinking the same..... Sounds like the Secondary Air Valve is too loose...

 

Listen to Dan and Racer Hog Bob

 

And if I may add.... Use a Electric Fuel Pressure Gauge inside your car.... Never a Mechanical Gauge.. Thats just asking for trouble if it develops a leak in the hose inside the cab of the car or truck !!!!!! Mechanical fuel gauges SHOULD ALWAYS be mounted outside...

 

Hey Imperial, I read that article and it is WRONG! It is adding Initial+Mechanical+Vacuum Advance to get to 35 degrees, I've never heard anyone, ever suggest to do that. I know you don't have vacuum, which is probably good for that cam and if you do a gear change. A Mopar article somewhere says initial+Mech+Vac will be 50-55 degrees great for cruising speed and fuel mileage.




The number you want is "IN the Distributor" The Mechanical Advance is critical and stays the same subtracted from 35 = Initial timing.

To change what is in the distributor it will have to come apart unless it has some means of bolting, fixing, changing the works inside.

I would not be surprised if your engine likes 20 degrees initial then you would want ONLY 15 in the distributor.

Looked up your distributor and found it has easily adjusted mechanical advance=BONUS!

I cannot stress enough how important it is to know this number. Then comes total at what rpm (easy with springs) then carb tuning.

 

thanks for all the help alot of new info to take in. im going to look up this secondary air valve deal see if my carb book says anything about hwo to make it "tighter" yeah....... had a mechanical oil pressure gauge in my mustang i used to have stupid thing decided to leak everywhere inside the dash lol never did get it all clean.

as for the stock converter hughes told me i wouldn't have any problem with this cam with my stock stall, plus you cant buy one, have one built or even use my converter to make one there are zero options for a converter with this trans cause its the A727 with 27 spline or what not. there is a way to adapt it over but you have to find the parts to do it. supposedly any tranny shop that knows anything can do the parts swap which changes the spline count so i can use any newer 727 converter. I dont know how much this costs and i dont know what any of the parts are called. I also think my timing is off thats making it idle a little different in turn making it run rich smelly too, I read with larger cams you have to make them run more rich anyways is this true?

Update read my carb book: that secondary air valve sounds like the exact problem i'm having, the book even said if its too loose it can even be slightly open even at idle causing for a rich running at idle and cruising speeds, seems easy to adjust i just adjust it 1/4 turns counter clock wise and test it till the problem goes away. going to wait till Monday to do this, that's when i get my tags and ill have my exhaust put on it by then so i don't get pulled over for not being registered, cant believe i've not been pulled over yet for open exhaust xD -- Ill keep you guys posted thanks for all the input!

 

http://billetconverters.com/super-la...-chrysler.html

Maybe PTC or Cope.

 

Not my words but I agree completely, this is where you start and if you are using a 50 year old damper or a new replacement part, you need to know that TDC is accurate on a performance build.

Thanks Dan

 

Try to notice any difference before it gets hot. What is/was the ambient temp when you had the symptom?

 

Could be ign miss fire ? Maybe try re routing the ign wires

 

Got it checked the guy said the timing was fine, it was 14 degrees, i adjusted the secondary air flap and its running alot better still sputters WOT im still adjusting it little at a time, got it registered today so now i dont have to worry about getting pulled over. ill keep you updated it seems so far its the secondary flap the carb book even named liek all the symptoms of it being too lose which im having. hope this fixes it cause i have other issues now with the battery not charging so i have to keep it on the 2amp charge every time i park in the drive way think my battery might die soon its died and been recharged about 20 times now & also a new symptom when starting the starter makes a squeeling sound and sounds liek its trying too hard, it never used to , i re tightened my belts i don't think its the belts got them tight as i could pulling the adjuster pull then tighten and pulling the alternator hard as i could then tightening. seems everything starting to go down hill again, I have a thread open on that issue if anyone knows electrical stuff. Link is here: https://moparforums.com/forums/f81/a...battery-19729/

 

A little at a time will get it fixed... Just keep chipping at it...Your doing just fine.