440 breaking up at 5600 RPM

-
Carnut76

Carnut76

Well-Known Member
Joined
Feb 14, 2016
Messages
91
Reaction score
21
Location
Kingston Illinois
At my wits end, have a 440 10:1 flt top pistons 440 source heads with new comp 924 springs, Lunati voodoo cam, 494-513 Holley 780 street avenger carb with 75s front and 80s rear 1.6 power valve, new MSD pro billet dist. new msd digital 6al, new msd superconductor wires, new edelbrock fuel pump. (checked pressure running down the road holds 6psi) ran the Digital 6al ground straight back to the battery in the trunk, have the pos. running to the ford relay where the giant small strand 600 volt pos. battery cable runs to under the hood. I have a converted one wire Denso alt running to the same terminal. I have changed spark plugs from platinum to copper core and gapped at .035 made no difference, running a mix of Cam2 110 and 90 octane recreational gas (non ethonal) have the engine grounded to the K frame with 4 guage copper wire. All of these changes and no difference except when I went from 78s in the rear jets to 80s it seemed almost worse. Fortunately I live in the country so I was able to run the car up to the breakup point and shut it off to coast into the garage, then I pulled a plug, looks a little lean maybe? Car runs like a champ up to the breakup point. Yes I checked the rev limiter as well seems to be accurate. Anyone see anything wrong with my setup? Sorry about the wordy description just trying to eliminate some questions. Thanks!

20160814_204510[1].jpg
 
Just curious, did Lunati recommend Comp springs?
 
Whats running voltage : At the alternator battery positive post,Ford starter relay, and running voltage,back at the battery...Running voltage,at least:13.8-15.0 ..(How old,is the battery?) Check the cheap basics first, unless you know already....
 
Abodybomber said:
Whats running voltage : At the alternator battery positive post,Ford starter relay, and running voltage,back at the battery...Running voltage,at least:13.8-15.0 ..(How old,is the battery?) Check the cheap basics first, unless you know already....
Click to expand...
Brand new Optima yellow top. Haven't checked voltage yet but I was just assuming it was good. Will put the meter on tonight.
 
RustyRatRod said:
Just curious, did Lunati recommend Comp springs?
Click to expand...
Lunati recommended their spring which was too narrow for the source heads, called 440 source and gave them the cam specs and they recommended the comp double spring at the installed height the head is set at, compared the two and they were pretty close to the same pressures, the comp being just slightly more than the lunati spring but the installed height is .025 higher than recommended for the comp soring so should equal out to the same pressure as the lunati spring recommended. Withing a few pounds. Not sure if I explained that where it makes any sense but I can post the spring numbers with installed heights.
 
Carnut76 said:
Lunati recommended their spring which was too narrow for the source heads, called 440 source and gave them the cam specs and they recommended the comp double spring at the installed height the head is set at, compared the two and they were pretty close to the same pressures, the comp being just slightly more than the lunati spring but the installed height is .025 higher than recommended for the comp soring so should equal out to the same pressure as the lunati spring recommended. Withing a few pounds. Not sure if I explained that where it makes any sense but I can post the spring numbers with installed heights.
Click to expand...
WOW, following this one. sounds exactly like what I did when I rewired my car. haven`t got mine that far tho, been chasing oil leaks. keep us posted on this one !----bob oh yea, looks like the heat range might be just a hair off ????
 
A vacuum gauge might help sort out if it is a valve problem. The vacuum might get jumpy and decrease at limit.

Ignition current demand increases with RPM. I assume the power feed is direct to battery, with red wire enable to switched ignition. Ignition problems can be very RPM specific. Use timing light on one plug wire, see if light cuts out at limit.

Fuel related issues are often absent at no load, and show with load.
 
Last edited:
I had the same exact problem and then i broke a valve and toasted a 15,000 dollar engine turns out those rocker shafts from 440source were not hardend right and the bearings on the rockers ate into the shaft i chased jets electric ingintion etc for months before it finally dropped a valve please do yourself a favor and check those rockers and shafts if you are using the 440 source stuff so you dont end up like me
 
moparwillybb said:
I had the same exact problem and then i broke a valve and toasted a 15,000 dollar engine turns out those rocker shafts from 440source were not hardend right and the bearings on the rockers ate into the shaft i chased jets electric ingintion etc for months before it finally dropped a valve please do yourself a favor and check those rockers and shafts if you are using the 440 source stuff so you dont end up like me
Click to expand...
I appreciate that I just had the rocker shaft off to change valve springs I had a little wear but they didn't look too bad
 
Any wear is to bad it throws the geometry off and side loads the valve then they start hanging up in the guide then they break
 
You said you have the engine grounded to the k frame. For my 2 cents I would run a ground strap from each head to the fire wall because k frame is not one of the best places. Most mopars run a ground from the engine to the frame rail and the fire wall
 
jockeyshift said:
You said you have the engine grounded to the k frame. For my 2 cents I would run a ground strap from each head to the fire wall because k frame is not one of the best places. Most mopars run a ground from the engine to the frame rail and the fire wall
Click to expand...
Might try that tomorrow, going to run the pos. straight from the MSD box back to batt. as well. We changed the carb tonight and still had the same results.
 
moparwillybb said:
Any wear is to bad it throws the geometry off and side loads the valve then they start hanging up in the guide then they break[/QUO
Didn't have enough wear to justify changing, they were more shiny but not worn down, I may change to roller rockers and new shafts soon. You must have had a substantially larger cam too? My cam is only 513 hyd.
Click to expand...
 
The comment regarding more grounds is spot on. You really cannot have too many.
 
Check your entire fuel line for kinks etc.... You are running 3/8 right ?

I went through a near identical experience with a W2 .638 roller motor... Changed entire ignitiin system, rejetted many times,
Never could figure it out.
Then one day I was changing gears and I looked up at the fuel line coming out of the tank....it was kinked ! Fabbed a new section of line and Voila .... problem solved...
 
mbaird said:
Check your entire fuel line for kinks etc.... You are running 3/8 right ?

I went through a near identical experience with a W2 .638 roller motor... Changed entire ignitiin system, rejetted many times,
Never could figure it out.
Then one day I was changing gears and I looked up at the fuel line coming out of the tank....it was kinked ! Fabbed a new section of line and Voila .... problem solved...
Click to expand...
Just replaced, brand new fuel system front to back no kinks, checked fuel pressure driving down the road holds 6 psi.
 
Carnut76 said:
Might try that tomorrow, going to run the pos. straight from the MSD box back to batt. as well. We changed the carb tonight and still had the same results.
Click to expand...
As suggested in post #7.
The MSD needs the direct battery fed power, trying to get that from the ignition circuit is not good. The MSD relies on high peak currents, when boosting the voltage to charge the capacitor, that is then dumped into coil. Yes grounds important too, supply and returns, sum the voltage drops. The stock wiring is not up to to delivering the significant current that increases with RPM.
 
Just saying! I chased ignition and plugs and wires and everything else and completely ignored everything about valvetrain wear and malfunctions this motor had less than 1000 miles! Those shafts should have 0 wear they are not sacrificial metal they are suposed to be harder than the bearing not trying to be a dick just seriously wish i would have listened to the same warning that was given to me 5,000 bucs later!

Screenshot_2016-05-07-13-53-38.png


Screenshot_2016-05-20-10-35-55.png
 
My system was all new as well so I assumed that wasnt the issue... I must have kinked the line while doing something else like installing rear end.
Its worth a simple check. You might also want to backflush the line from the front with an air nosle in case something restricting flow.
I may be wrong but good pressure may not be the same as good flow volume.

Your issue sounds identical to mine.....

Good luck
 
moparwillybb said:
Just saying! I chased ignition and plugs and wires and everything else and completely ignored everything about valvetrain wear and malfunctions this motor had less than 1000 miles! Those shafts should have 0 wear they are not sacrificial metal they are suposed to be harder than the bearing not trying to be a dick just seriously wish i would have listened to the same warning that was given to me 5,000 bucs later!

View attachment 1714959011

View attachment 1714959012
Click to expand...
I appreciate, I know your not being a "dick" everything is relevant and the reason I posted the details including the type of heads I have is to see what others have experienced with the same parts, I definately am going to replace the shafts and arms but going to try to wire the msd to the battery and ground the heads first per msd recommendation. I just had the shafts off two weekends ago, they will show some wear from the friction but mine didn't have grooves, the rocker arm tip showed some wear but the shafts were more of a polished look. That being said new heads and or shafts and rocker arms will be next if the wiring doesn't fix the problem. Would love to upgrade to Indy heads but my teenage son needs braces which is equvilent to three sets of heads. I believe source heads are a good casting but they use some cheap hardware and they were pretty straight forward about it when I called about the valve springs they use. They straight up told me they were generic and that I should replace them.
 
Well, spent several hours routing my hot straight to MSD, ignition from the batt, and running a ground from the head to a body ground, MSD is grounded to the batt. made no difference.
 
Two hours for important stuff, sorry did not help. It will save you grief when bulkhead connector fails. It off loads ignition switch too.

Time for vacuum gauge test.
 
KitCarlson said:
Two hours for important stuff, sorry did not help. It will save you grief when bulkhead connector fails. It off loads ignition switch too.

Time for vacuum
Click to expand...
moparwillybb said:
Just saying! I chased ignition and plugs and wires and everything else and completely ignored everything about valvetrain wear and malfunctions this motor had less than 1000 miles! Those shafts should have 0 wear they are not sacrificial metal they are suposed to be harder than the bearing not trying to be a dick just seriously wish i would have listened to the same warning that was given to me 5,000 bucs later!

View attachment 1714959011

View attachment 1714959012
Click to expand...
moparwillybb said:
Just saying! I chased ignition and plugs and wires and everything else and completely ignored everything about valvetrain wear and malfunctions this motor had less than 1000 miles! Those shafts should have 0 wear they are not sacrificial metal they are suposed to be harder than the bearing not trying to be a dick just seriously wish i would have listened to the same warning that was given to me 5,000 bucs later!

View attachment 1714959011

View attachment 1714959012
Click to expand...
I rewired the msd and no change, I ran the car up slowly into the breakup point around 6k and let off , it actually sounded like one cylinder missing for a few seconds after then it cleared up, what ecxactly did your engine problem sound like? Do them cheap shafts actually flex under pressure or just break?
 
You must log in or register to reply here.
-

Back
Top