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Discussion Starter #1
Don't beat me I am asking for a friend that owns a 1970 440 Six Pack Charger and just can't get it to run right at all. The motor is running 10.5 .30 over pistons, slightly modified heads, headers has used multiple center carbs, blocked off the outer carbs and needs to adjust the idle up all the way to get it to run. If he disconnects the PVC valve hose it runs much better. He thinks its the cam. I think it's a carb issue but he has proved that it is not. He had used an electric pump in a bucket with a regulator to isolate over pressure condition. This is a very nice car and has been looked at by many professionals. I have heard it run in the past and the cam seems to be pretty hot IMO. I am going over this weekend to take a look. BTW, compression is good and even, he couldn't remember the #'s though. He is disgusted with this car and has just given up until now. I have posted his cam spec card for your reference. Thanks in advance for your thoughts on this.
 

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First thing that comes to mind is timing, cam and/or ignition. Check cranking compression, it would give some what of an idea if the cam was close.
 
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Discussion Starter #3
First thing that comes to mind is timing, cam and/or ignition. Check cranking compression, it would give some what of an idea if the cam was close.
Any idea on the cam specs. Too hot for the street? The basics have all come back with nothing. Like I said he thinks its the cam. Would a cam cause an extreme rich condition. It looks hot to me but not overly hot for the street. I have run cams nearly that hot in a SBC but its the Overlap that has me baffled. I am certainly not a cam expert.
 

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Doesn't look that big not a whole lot of lift. OL looks to be 84 deg. Should idle around 1000 if timing is good.
 
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Start with the basics, ie, the timing chain is installed properly. Then make sure the Dist is properly installed. Set timing with a light and record. Record all changes.

This should have shaft rockers, make sure the shafts are installed on the correct sides and proper orientation, and there is not a issue with adjustment or pushrod length.

The giving it more air by pulling the pcv indicates its running way rich on the center carb.

Check the center carb for jets, idle passages and internal leaks, and make sure the throttle plate is in the correct orientation re the idle slots at idle, and also goes wide open with the pedal.

Random issue my 383 had was the coil wire broke all but a couple strands. It would start, run, and when it warmed up it would sputter and not run above idle! Hard to figure out!

Also check the famous mopar firewall mounted ballast resistor for being intact and not open.
 

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If they are Holley carbs might have backfire & blown the power valve, that will make it rich.
 
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Discussion Starter #7
Start with the basics, ie, the timing chain is installed properly. Then make sure the Dist is properly installed. Set timing with a light and record. Record all changes.

This should have shaft rockers, make sure the shafts are installed on the correct sides and proper orientation, and there is not a issue with adjustment or pushrod length.

The giving it more air by pulling the pcv indicates its running way rich on the center carb.

Check the center carb for jets, idle passages and internal leaks, and make sure the throttle plate is in the correct orientation re the idle slots at idle, and also goes wide open with the pedal.

Random issue my 383 had was the coil wire broke all but a couple strands. It would start, run, and when it warmed up it would sputter and not run above idle! Hard to figure out!

Also check the famous mopar firewall mounted ballast resistor for being intact and not open.
I hear both you and Jim and you are coming across like I did.The shaft rockers you mentioned I would like to know more about. I personally know the mechanics that have worked on it and they are top notch but that doesn't mean they missed something. They double checked cam and ignition timing. The pushrod length is also interesting. I wonder why they say you must use their lifters on the cam card. I asked him if he did but couldn't remember. Its been a lot of years since the build. They have replaced the center carb and blocked off (literally removed) the end carbs and put a plates in place. Obviously they have overlooked something but what would pro's miss. Thanks guys
 

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Discussion Starter #8
So the cam was installed at 0 no advance or retard. Rockers are adjustable shaft mounts.

Does anyone have input on the cam specs? The overlap seems strange to me but then again I am not a Chrysler guy nor am I familiar with Norris cams.
 

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Discussion Starter #10
I thought those 6 packs used all 3 carbs for the correct idle.
Here is a bit of reading on post 18.
https://www.forbbodiesonly.com/moparforum/threads/six-pack-idle-mixture-screws-dont-do-much.94876/


I would care less what other mechanics tested. I test everything for myself.
Leaving something untested because someone said it was good and that someone could not fix it would not go very far with me.

Start from scratch and get it fixed. Make all 3 carbs operable.
I agree.. Thanks
 

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Since Mopars use non adjustable rocker shafts, who's to say that the rocker shafts don't need some shims where they are bolted down. Years ago, that was talked about whenever a change from the original factory cam was happening.
 

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Big cams make engines really hard to tune for street manners. If vacuum is low, PCV system basically becomes a big vacuum leak. Been there/done that. In your friend's shoes I would ditch that cam, install something close to stock, and go enjoy what sounds like an otherwise awesome car. JMHO
 
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That an old Norris grind. Looks to be in the 80's, 90's at the latest. I don't know the exact specs but I will bet the .050 numbers are between 240-250 duration.

Does he have enough timing at idle? For this he could even use a locked distributor at 38 for a start.

Is this a auto or manual trans?

Is Norris still in business? If so give them a call and get the exact specs. His car may behave much better with about 20 degrees less duration.
 

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Norris closed up shop in 2008, so they aren't gonna be able to help any.
 

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Discussion Starter #15
That an old Norris grind. Looks to be in the 80's, 90's at the latest. I don't know the exact specs but I will bet the .050 numbers are between 240-250 duration.

Does he have enough timing at idle? For this he could even use a locked distributor at 38 for a start.

Is this a auto or manual trans?

Is Norris still in business? If so give them a call and get the exact specs. His car may behave much better with about 20 degrees less duration.
Its a number matching track pack car, 4 speed. He went with crane adjustable rockers, L2355f +.30 pistons that should yield around 10 to 1. All cam associated parts are Norris so there shouldn't any issues there like coil bind, etc.
 

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Its a number matching track pack car, 4 speed. He went with crane adjustable rockers, L2355f +.30 pistons that should yield around 10 to 1. All cam associated parts are Norris so there shouldn't any issues there like coil bind, etc.

Sounds good. I really don't think his timing curve is near fast enough and not enough initial advance. Once that is corrected then work on the carb if it still will not idle. A lot of "carb problems" are often fixed with the correct timing and advance.

A stick shift trans will handle the cam much easier than an auto.
 

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Here,s my two cents . First from what i can see of that cam card it ,s got 300 *duration and a 108 lobe center. That in itself will make for a real choppi idle. Once yo go over 60 * it starts to get choppi but thats a 440 and can take a good amount of cam. Has anybody ruled out the timing chain being a tooth off or the distributor being a tooth off. It will still start and run but not good. I also think thats a big cam for the street. Is it a stick or a torqueflyte if its an auto you need some converter for that easier with a stick. Multiple carburetiontakes a bit to get adjusted i have the gm tool with the hoses the mecury vial and the covers to sychronise trips but it wil only fit rochesters for a j-2 set up for a goat. Like jeff said i would not take anybodies word that this or that is ok . Start from scratch and check everything including vacuum leaks valve adjustment etc. I would change out the cam as i think its a tad big. If you going flat tappet and i like to use them try howards or isky as they are trouble free as far as worn out lobes and lifters its good stuff. Hope this helps. Alex
 

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Slightly off-topic, but funny (to me anyway) -

How many "What Cam Do I Need?" topics, where guys are recommending bigger, bigger, and bigger cams, are followed right up by another topic where somebody who went with one of these huge cams can't get their car to run worth a damn? :)
 

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With all that duration and overlap on a street motor, I'd lock the timing... If your running points, just remove the springs to the weights, that way you'll have a start retard..
 

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First, check the initial timing. needs at least 20 with that cam. vacuum advance hooked up to manifold vac too. the mechanical advance in the dist will need to be limited to keep from having way too much at RPM. But first, jack the initial to 20 or so, see if things aren't much better.
 
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