Weird noise after 4 speed install

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What cam are you running? 268/276/110 Voodoo703
Are you running Solid lifters? nope.
What's the idle speed? 800
the Idle-timing? 18*
the Setting of the Idle-mixture screws? fi-tech EFI
Have you set the T-slot sync? is none
OOps some of that is in Post 47

IMO
because she sounds to be idling pretty fast, with a lot of timing, most likely the T-slot to mixture screw relationship is out of whack and the engine is just struggling with AFR. Make sure your secondaries are closed up tight but not sticking.
Furthermore, at 18* timing, your engine is making too much idle-power, and the power-pulses are hammering the driveline.

I had your exact combo a few years ago, except with a Hughes cam, and 11.3Scr. I idled it at 14* in the distributor and 650/700 rpm in Neutral, with no bypass air. My T-slot exposure was square.
To reduce the power for parading, I reset the idle-timing to 5*.
That cam would idle at 500/550 in low gear@ 5* advance, pulling itself all around the parking lot, with no help from my big right foot, nor the left one. With 3.55s, that was 4.25 mph with the standard 2.66 low, and with the 3.09, it was 3.6mph
I ran the cooling system at 207*F

But I just gotta say, man that sounds like a lotta valve-train noise.Mine was quiet as can be.
 
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AJ/FormS said:
What cam are you running? 268/276/110 Voodoo703
Are you running Solid lifters? nope.
What's the idle speed?
the Idle-timing? 18*
the Setting of the Idle-mixture screws?
Have you set the T-slot sync?
OOps some of that is in Post 47

IMO
because she sounds to be idling pretty fast, with a lot of timing, most likely the T-slot to mixture screw relationship is out of whack and the engine is just struggling with AFR. Make sure your secondaries are closed up tight but not sticking.
Furthermore, at 18* timing, your engine is making too much idle-power, and the power-pulses are hammering the driveline.

I had your exact combo a few years ago, except with a Hughes cam, and 11.3Scr. I idled it at 14* in the distributor and 650/700 rpm in Neutral, with no bypass air. My T-slot exposure was square.
To reduce the power for parading, I reset the idle-timing to 5*.
That cam would idle at 500/550 in low gear@ 5* advance, pulling itself all around the parking lot, with no help from my big right foot, nor the left one. With 3.55s, that was 4.25 mph with the standard 2.66 low, and with the 3.09, it was 3.6mph
I ran the cooling system at 207*F

But I just gotta say, man that sounds like a lotta valve-train noise.Mine was quiet as can be.
Click to expand...

I'm running Fitech Fuel injection so it's a bit different than a carb.

My idle speed is 800, I can adjust this down along with my idle timing with a touch of a button.

My AFR at idle is 13.4 ish, can also be set.

I didn't think the valve train was loud, but I guess I have nothing to compare it to. I'll pull the plugs tonight and remove the valve covers and inspect.
 
Before adjusting the idle timing in the FiTech software I would throw a light on it and see what your distributor is installed at. I don't believe the FiTech allows your idle timing to be set lower than what the dizzy is stabbed in at. ( I could be wrong on that one though) Mine is stabbed in at 18 degrees, and I run 20 degrees at idle and 34 pretty much anywhere else, it works with my setup.
 
72Duster440 said:
Before adjusting the idle timing in the FiTech software I would throw a light on it and see what your distributor is installed at. I don't believe the FiTech allows your idle timing to be set lower than what the dizzy is stabbed in at. ( I could be wrong on that one though) Mine is stabbed in at 18 degrees, and I run 20 degrees at idle and 34 pretty much anywhere else, it works with my setup.
Click to expand...

That is the first thing I checked after cam break in. I set the unit to "locked" and 30 degrees on the handheld. Then double checked the timing on the balancer at 2K and 4K to be sure they were the same (on the balancer and the handheld) and they were. I then unlocked the timing on the handheld, which reverted back to 18 deg idle adv (what is set in the handheld) and that is what the balancer showed also.

I do know that you can set your "start" timing separate from your idle timing. I have mine both set to the same.
 
plumkrazee70 said:
I didn't think the valve train was loud, but I guess I have nothing to compare it to. I'll pull the plugs tonight and remove the valve covers and inspect.
Click to expand...
Hang on a day or two, to see if others agree with me. It may just be my laptop.
Furthermore, I think Voodoo cams have a reputation of being loud.

Where did you install the O2's?
Are they on-line at idle?
Are the headers sealed both at the head and at the merges and the collectors?
Headers are like suction pumps. If they are not sealed, they will vacuum in air, which is guaranteed to upset the signal coming out of the O2.
Furthermore, that cam has a good deal of overlap, 52* by the math. At idle, the pipes could be suctioning plenum A/F charge right across the top of the piston. Of course that would upset the O2s as well.
IMO
the best idea is to shut the O2s off at idle and build an open-loop idle-tune without them.
 
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My Fitech idled like that too with out of the box settings.
I had to go in and make a handful of changes. The big ones being the amount of timing adv/ret to help stabilize the idle. I also slowed down the idle motor response time and idle fuel rate of change quite a bit (nearly half the default values). It seemed like those three things would kind of screw with one another and caused me no end of headaches as they fought one another.
The spark stability feature is the way to control the idle IMO. I'd have to look through the manual to remember the names of each of those settings, but in effect I dialed the IAC rates down and the speed of the mixture changes. Now my idle is most stable and the AFR is far more consistent at idle.

What is your IAC reading when warm?
 
AJ/FormS said:
Hang on a day or two, to see if others agree with me. It may just be my laptop.
Furthermore, I think Voodoo cams have a reputation of being loud.

Where did you install the O2's?
Are they on-line at idle?
Are the headers sealed both at the head and at the merges and the collectors?
Headers are like suction pumps. If they are not sealed, they will vacuum in air, which is guaranteed to upset the signal coming out of the O2.
Furthermore, that cam has a good deal of overlap, 52* by the math. At idle, the pipes could be suctioning plenum A/F charge right across the top of the piston. Of course that would upset the O2s as well.
IMO
the best idea is to shut the O2s off at idle and build an open-loop idle-tune without them.
Click to expand...

Its only 1 o2 sensor and its welded in after the collector, I forget how many inches. It has full length exhaust on it as well.
Yes, the 02 is reading immediately at idle
I have no reason to believe the headers are not sealed (brand new remflex gaskets on head and collector, when aluminum heads when in)
Not sure the Fitech has the ability to turn off the 02
 
Phreakish said:
My Fitech idled like that too with out of the box settings.
I had to go in and make a handful of changes. The big ones being the amount of timing adv/ret to help stabilize the idle. I also slowed down the idle motor response time and idle fuel rate of change quite a bit (nearly half the default values). It seemed like those three things would kind of screw with one another and caused me no end of headaches as they fought one another.
The spark stability feature is the way to control the idle IMO. I'd have to look through the manual to remember the names of each of those settings, but in effect I dialed the IAC rates down and the speed of the mixture changes. Now my idle is most stable and the AFR is far more consistent at idle.

What is your IAC reading when warm?
Click to expand...

I am starting to really think its in the tune. I have the Fitech controlling the timing and I have verified that the handheld and the motor are in sync. However, I haven't checked the rotor phasing (I have the adjustable rotor and the dist locked out).

The IAC readings are around 6 warm, after I set the timing I made sure to set that next. They say between 3 and 10. I can take some pics of my settings, I am open to going through it and making some changes, just not sure where to start.
 
Under 'AFR closed loop' (in the pro tuning section. You typically need to go into the display settings and enable pro tune) you'll find:
AFR loop speed. I reduced this about by about 10 numbers.
Idle trim rate pos and neg, I cut these in half.
There's a section for 'idle stability spark' or similar. The default values are something like -3 -1 0 +.5 +3 +5 degs for various rpm fluctuations. I narrowed the range a bit and then also took a couple degrees out of my idle timing so that when it adds the max it doesn't cause a shudder. I've got a 408 with around 300 advertised duration, so my idle timing is 22-24 deg.
Last is the loop rate under 'idle control'. This controls the reaction speed of the IAC motor. I cut these values about in half as well.

I'd focus on the idle trim rate first, then the loop rate. Cut them both in half to start, and then maybe play with the idle stability spark if you still have issues. I'd leave this for last though, I think I wound up moving things less than a degree total from the stock settings.
 
Phreakish said:
Under 'AFR closed loop' (in the pro tuning section. You typically need to go into the display settings and enable pro tune) you'll find:
AFR loop speed. I reduced this about by about 10 numbers.
Idle trim rate pos and neg, I cut these in half.
There's a section for 'idle stability spark' or similar. The default values are something like -3 -1 0 +.5 +3 +5 degs for various rpm fluctuations. I narrowed the range a bit and then also took a couple degrees out of my idle timing so that when it adds the max it doesn't cause a shudder. I've got a 408 with around 300 advertised duration, so my idle timing is 22-24 deg.
Last is the loop rate under 'idle control'. This controls the reaction speed of the IAC motor. I cut these values about in half as well.

I'd focus on the idle trim rate first, then the loop rate. Cut them both in half to start, and then maybe play with the idle stability spark if you still have issues. I'd leave this for last though, I think I wound up moving things less than a degree total from the stock settings.
Click to expand...

Thanks, I want to make sure everything is firing like it should first before I make any major adjustments. Do you have the Fitech controlling timing?
 
plumkrazee70 said:
Thanks, I want to make sure everything is firing like it should first before I make any major adjustments. Do you have the Fitech controlling timing?
Click to expand...

I do. I've been through lots of trial and error with the thing too.

After some other work, and loading the latest firmware, I had it up and running again. I was kind of used to the way it ran, but had a couple folks ask me if it had a vacuum leak because it sounded rough. That made me dig into it further and really try to smooth things out. The difference is pretty substantial.
 
plumkrazee70 said:
So do I. Did either of you @72Duster440 or @Phreakish have any trouble with the rotor phasing?
Click to expand...

None.
The base timing value in the handheld can be used to help adjust phasing some. Tough to explain, but that value adjusts the rotor relationship to the terminals to some extent. I haven't needed to do that yet though.

I put a hole in a spare cap and checked it, and found it to be pretty darn good. I run with a 15deg base timing, 22-24 initial, 34 total and 50 at low map cruise.
 
Phreakish said:
None.
The base timing value in the handheld can be used to help adjust phasing some. Tough to explain, but that value adjusts the rotor relationship to the terminals to some extent. I haven't needed to do that yet though.

I put a hole in a spare cap and checked it, and found it to be pretty darn good. I run with a 15deg base timing, 22-24 initial, 34 total and 50 at low map cruise.
Click to expand...

Which kpa is low map cruise? I could throw some more timing at mine, I'm more or less 34 everywhere currently.
 
plumkrazee70 said:
I am starting to really think its in the tune. I have the Fitech controlling the timing and I have verified that the handheld and the motor are in sync. However, I haven't checked the rotor phasing (I have the adjustable rotor and the dist locked out).

The IAC readings are around 6 warm, after I set the timing I made sure to set that next. They say between 3 and 10. I can take some pics of my settings, I am open to going through it and making some changes, just not sure where to start.
Click to expand...
Are you saying you have your timing locked out?
Somewhere in the middle for IAC, 1-10..so 6 is good.
It asked you what your idle timing was and what you're full Advance was as long as you put those in after checking them and they're accurate you should be good.
How about the cam selection 1 through 3 or something like that have you tried two yet or are you on three or?
 
72Duster440 said:
Nope, it was pretty easy. I set my timing where I wanted it then dialed the rotor back the same amount of degrees so it was aimed right at the plug wire tower.
Click to expand...

Ok, I dialed mine back also, but I can't remember how I came up.woth the figure. Lol. I have an extra cap, so I will do the same and make sure it's not trying to arch the next cylinder. It fires up hot or cold instantly, just idle is not very stable (clearly).

Hopefully post some results of my findings soon. Making dinner for the family now.
 
Mine shakes pretty good at idle, but it's got a big cam in it so I never gave it a second thought. I might try what Phreakish said to see if it tones it down a bit at idle, but it idled even nastier with the old carb on it.
 
MOPAROFFICIAL said:
Are you saying you have your timing locked out?
Somewhere in the middle for IAC, 1-10..so 6 is good.
It asked you what your idle timing was and what you're full Advance was as long as you put those in after checking them and they're accurate you should be good.
How about the cam selection 1 through 3 or something like that have you tried two yet or are you on three or?
Click to expand...

Yes, so the MSD distributor is locked out (it has no weights or springs) Fitech says to do this when it controls timing.

My idle timing is 18* I have the full advance set to 34* as a base line. I know the balancer matches the handheld numbers, I checked that right after the cam was broke in.

The cam selection I chose was 2. Haven't tried it on either other yet.
 
MAP is an absolute pressure, lower it reads means more vacuum.
I think the values are set at 45kpa and 98 or 100kpa. The 45kpa values are for cruise, 98 or 100 are WOT. It may even be labeled as WOT, I forget.

I have my idle at 24, 1100rpm 45kpa is 22 (makes it easier to feather the clutch), 1100rpm at 98kpa (WOT) is also 22. All the rest (3k and 6k I think) are 34 at WOT and 50 at 45kpa.

In the breakpoints menu (under pro tuning) you can change the cruise kpa (and also the low, mid, and high rpm), but I've found it doesn't really need it, even with a larger cam.

The higher advance at cruise helps lean out the cruise afr, which I run near 15. Idle afr is 14.5 to 15.2. I've found fine tuning the idle in 0.1 increments to be super important. I do a sweep from 14.2 to 16 in 0.1 increments every time I change idle timing. It's the only way to find the sweet spot each time. Also, keep checking those plugs as you do. By ear isn't 100%!

I've found that in general, more idle timing with a leaner mix will idle cooler and smoother and less stink. Less timing takes more fuel (lower afr) and a readjustment of the IAC steps.

From there, there's a million other settings to help driveability. Decel open IAC is super important with a 4spd. Too low, it'll be jerky as you tip in and out at cruise, too high it won't coast down when you take your foot out of it. If your timing is too high at WOT and low rpm, it'll be jerky or stumble or even stall easier. I've found a big pump shot and dipping the timing 2-3 degrees below idle timing helps make more torque and less apt to stall.
 
plumkrazee70 said:
Yes, so the MSD distributor is locked out (it has no weights or springs) Fitech says to do this when it controls timing.

My idle timing is 18* I have the full advance set to 34* as a base line. I know the balancer matches the handheld numbers, I checked that right after the cam was broke in.

The cam selection I chose was 2. Haven't tried it on either other yet.
Click to expand...

Cam 2 is probably right. It only changes fueling, not idle or pumpshot so just leave it for now.

I'd put your 1100rpm timing settings at 20 for now. Then tweak the stuff I mentioned before. Don't be afraid to cut them in half. See if it idles smoother. Also try tweaking the idle mix from 13.7 to 15 in 0.1 increments. I'd guess your cam would probably be happy around 14.5 at 18 deg. I also wouldn't hesitate to bump the timing to 20 or 22 deg either. Try the afr sweep at 20 and 22 to see if you notice any particular setting runs best.

I've run as high as 28 at idle and only dropped it some to give the spark stability more breathing room since it felt a little rough sometimes when the stability spark would add more than 3 degrees.
 
I don't know guys. I'm ready to throw in the towel. I tried all the above, checked the plugs, rotor, wires, cap, rockers, etc. Nothing is out of the sorts.

No changes madee it any better, except increasing the idle past 1100 RPM. Doing that smoothed it out.
I even sent a datalog to a guy who does remote tuning and we moved a few things, but no change. He thinks it's something else, besides the efi.
 
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