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Charger with 440 won't pull and rev enough? #1236054
05/19/12 06:20 PM
05/19/12 06:20 PM
Joined: Jul 2008
Posts: 179
Up in the North and Far Away
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AutoEngineer Offline OP
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AutoEngineer  Offline OP
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Up in the North and Far Away
Hi guys,

Please give me some fresh ideas what might be the trouble maker.

After a long winter period was taking today the 69 Charger R/T out of the garage for the maiden pass at 1/4mile with the new setup of 440 and could not get the motor to rev past 5500 rpm.

Today's best time at our local airfield 1/4 mile strip was 12.467s @ 112mph, with best 60ft time 1.944.
The track was very slippery, but traction was getting better after each run.
By the butt dyno the engine has capabilities for better times, but the engine won't rev past 5500rpm...

The new engine combo is as follows
ENGINE:
440 .055 over, SRP flat top pistons with valve reliefs
Compression Ratio: 10.5:1
Cylinder Heads from 440Source, fresh professional valve job and a mild bowl blend
Roller rockers with 1.6 ratio

Cam, Lunati hydraulic roller 60312
Intake Duration @.050: 231
Exhaust Duration @.050: 239
Intake Duration: 282
Exhaust Duration: 290
Lobe angle: 110 deg
Cam centerline: 106 deg, straight up
Intake Valve Lift: 0.571 with 1.6 rockers
Exhaust Valve Lift: 0.587 with 1.6 rockers

Valve springs: Lunati 73124: 150lbs seat pressure, 350 lbs open, as recommended by Tim @ Lunati.
All valve springs shimmed for exact seat pressures
Roller Lifters: Lunati by Morel, preload 3/4 turns, .0375"

Intake Manifold: Holley SD
Carb: 850 cfm Demon, mech. secondaries. Secondaries opening full.
Air filter K&N 14" with XStream Air Flow Top
A/F ratio on the track, constant 12.2...12.5, by an AF meter

Exhaust: Hedman Headers 1 3/4" primaries, 3" collectors. 2" full length exhaust with X pipe,
BUT tried today also with open exhaust, NO help with open exhaust still would not rev past 5500 rpm

IGNITION
Distibutor: Mopar Performance, .008 reluctor cap.
Even two different dist. used today
#1 With recurved mechanical advance, 18 deg.initial and 34 total, vacuum advance NOT connected
#2 With stock mechanical advance, 15deg initial and 39 total, vacuum advance NOT connected. Pulled better with this dist. and no pinging.
Dist bushings are tight on both dists.

ECU, tried today with two different ECU's,
#1 Vintage Mopar Orange box from the 80's with MSD Blaster 2 coil and matching ballast
#2 FBO ECU with FBO coil and ballast
No rev limiter
Spark plugs: Denso with .042 gap
Dist, coil and ECU wiring double checked.

Fuel pump: Old work horse, mechanical high volume Carter M6903, 120 GPH flow rate. Has brand new push rod with brass tip for the steel cam.
Fuel line: stock of a 69 Charger R/T 440

Weight of the Car: 4100
Transmission: Automatic with B&M converter, 3000 stall
Gear Ratio: 3.73
Tires ET Street radials, 28 x 11.50R15

Car runs great down low and pulls hard, just seems to run out of steam at about 5000 rpm and is hitting a wall at 5500 with little banging or sputtering.

Do you have any new ideas on what might be the reason???

Re: Charger with 440 won't pull and rev enough? [Re: AutoEngineer] #1236055
05/19/12 07:03 PM
05/19/12 07:03 PM
Joined: Mar 2008
Posts: 5,744
Ontario, Canada
Dodgem Offline
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Dodgem  Offline
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Where up north?
anyway nothing jumps out.



Did you degree the cam?? I would have installed it at 105.

Usually three four things things limit your RPM
1. Fuel delivery but if you AF number did not suddenly climb doubt that's it

2. Valve spring float since you have new and I assume checked to see if it was not coil binding should not be hear.

3. ignition since you tried some different not hear although I like .004 gape.

so likely one of these two and most likely the first.

4. way too much pre load on the lifters and it's forcing the valve float.

5. spark plugs I would have used Chanpion RN12YC or RC12YC

Good luck!




Re: Charger with 440 won't pull and rev enough? [Re: Dodgem] #1236056
05/19/12 08:35 PM
05/19/12 08:35 PM
Joined: Jan 2003
Posts: 9,648
Weddington, N.C.
Streetwize Offline
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Weddington, N.C.
The very FIRST thing I'd check is for corrosion in the fuel line...usually the pick-up/sending unit sock.

Next, as said that cam is in way late for a heavy car....105-106 would be where I'd put it. Actually with a HR a single pattern 239 in at 102-103 would be even better. Lunati's are notorious for requireing Degreeing from my experience, never trust the factory ground-in advance without verifying it.

Also I agree the pre-load may be tight, try backing them off 1/4 to 3/8 of a turn from where you got them. if no improvement tighten them back up. I set them at 3/8 to no more than 1/2 and never had issues and my 517 turns 6800 with a (Bullet) juice roller.

That's not a lot of stall for what you have, I like about 3400-3600 FB/stall and 4200 flash for that combo. with what you describe you should run a very low 12 or even high 11 without too much trouble.

Check the fuel line first, corrosion will choke that thing down big time, People have brought me cars that had all the goods but wouldn't fall out of a tree....I pulled the fuel pick-ups where I was amazed it had enough fuel flow to IDLE, let alone take full throttle under load

Last edited by Streetwize; 05/19/12 08:38 PM.

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Re: Charger with 440 won't pull and rev enough? [Re: AutoEngineer] #1236057
05/19/12 09:41 PM
05/19/12 09:41 PM
Joined: Jul 2003
Posts: 3,355
Rancho Cordova, CA
Exit1965 Offline
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Exit1965  Offline
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Rancho Cordova, CA
Sounds like you know your specs. But I didn't see jet size listed. My mighty demon came with WAY undersized secondary jets and I couldn't figure out why it ran like crap when getting on the gas. Yours doesn't sound that bad but I would verify that the right jets are in there.

While you're in there you might find metal shavings, incompletely drilled passages etc which could be plugging something up.

Re: Charger with 440 won't pull and rev enough? [Re: AutoEngineer] #1236058
05/19/12 10:38 PM
05/19/12 10:38 PM
Joined: Jan 2003
Posts: 1,261
Mission BC
10sec440 Offline
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Quote:



Fuel pump: Old work horse, mechanical high volume Carter M6903, 120 GPH flow rate. Has brand new push rod with brass tip for the steel cam.
Fuel line: stock of a 69 Charger R/T 440





This is your problem IMO. You're making well over 500HP with that combo I would think, in a 4100lb vehicle you need more fuel than that.If you don't want to upgrade your fuel system for whatever reason, get some float bowl extenders. Moroso makes them.

Last edited by 10sec440; 05/19/12 10:41 PM.
Re: Charger with 440 won't pull and rev enough? [Re: 10sec440] #1236059
05/19/12 11:09 PM
05/19/12 11:09 PM
Joined: Dec 2005
Posts: 1,477
Shelby mi.
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JAKE68 Offline
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JAKE68  Offline
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Shelby mi.
I wouldn't think based on your a/f ratio that you have a fuel system problem,but your symptoms sure seam like it. I have found in the past that a hyd. roller likes 0 lash to get them to rev??? Just saying. I have dyno tuned some cars that would hit a wall at 5000 rpm and then pick that extra rpm when we backed off the preload.


JAKES AUTOMOTIVE
Re: Charger with 440 won't pull and rev enough? [Re: JAKE68] #1236060
05/19/12 11:44 PM
05/19/12 11:44 PM
Joined: Jul 2005
Posts: 1,472
Overland Park, KS.
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Joshs68 Offline
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What balancer is on the engine and if it is the stock unit has it spun? I had one that did and I reset the timing after it had moved. Otherwise I have nothing.

Re: Charger with 440 won't pull and rev enough? [Re: AutoEngineer] #1236061
05/20/12 04:45 AM
05/20/12 04:45 AM
Joined: Nov 2003
Posts: 1,154
Out of the State of Confusion
blue_stocker Offline
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Hi Jukka-
If you haven't verified 6-7 psig fuel pressure or verified the fuel line from the tank is adaquately delivering fuel, do that first. REGARDLESS of what components you're using, verify the fuel is getting to the intake both in volume and in pressure. You should also have some (gauged) means to ascertain fuel pressure at top end/going through the lights. Next, verify fuel level is correct in the carb bowels, then check and read your plugs for proper jetting, make sure she's not banging from being lean on the jetting, you won't like dropping a hole in a piston! Hope all else is going well for you and drop me an email when you feel up to it...wb

BTW, junk the Mopar ECU-ballast resistor and install some form of GOOD box, Mallory/MSD/Crane/Jacobs, something that won't leave you hanging.

Re: Charger with 440 won't pull and rev enough? [Re: blue_stocker] #1236062
05/20/12 07:45 AM
05/20/12 07:45 AM
Joined: Dec 2005
Posts: 1,477
Shelby mi.
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JAKE68 Offline
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JAKE68  Offline
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Shelby mi.
Quote:

Hi Jukka-
If you haven't verified 6-7 psig fuel pressure or verified the fuel line from the tank is adaquately delivering fuel, do that first. REGARDLESS of what components you're using, verify the fuel is getting to the intake both in volume and in pressure. You should also have some (gauged) means to ascertain fuel pressure at top end/going through the lights. Next, verify fuel level is correct in the carb bowels, then check and read your plugs for proper jetting, make sure she's not banging from being lean on the jetting, you won't like dropping a hole in a piston! Hope all else is going well for you and drop me an email when you feel up to it...
BTW, junk the Mopar ECU-ballast resistor and install some form of GOOD box, Mallory/MSD/Crane/Jacobs, something that won't leave you hanging.



those kind of fuel problems should show up in his a/f.


JAKES AUTOMOTIVE
Re: Charger with 440 won't pull and rev enough? [Re: JAKE68] #1236063
05/20/12 01:59 PM
05/20/12 01:59 PM
Joined: Jan 2003
Posts: 1,261
Mission BC
10sec440 Offline
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10sec440  Offline
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What are you using to measure A/F? is it 12.2 while its actually acting up? Either way that's not enough fuel for that combination.If it isn't starving for fuel now, when you get it to go over 5000rpm it surely will be. Also you have jet extensions on the rear jets right?

Re: Charger with 440 won't pull and rev enough? [Re: 10sec440] #1236064
05/20/12 04:33 PM
05/20/12 04:33 PM
Joined: Jul 2008
Posts: 179
Up in the North and Far Away
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AutoEngineer Offline OP
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AutoEngineer  Offline OP
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Up in the North and Far Away
Hi guys,

Thanks a lot for all your valuable input.
Here's some more information from the setup.

- Before the first run that Demon carb was disassembled, cleaned and checked for all possible manufacturing faults.
- Primary jets are #80 and secondaries #86.
- Correct fuel level checked and adjusted
- Max fuel pressure set at 6 psi with Holley regulator
- A/F ratio is measured by an old A/F meter and lambda sensor is placed on the left header collector.
However I have now a strong assumption that either the A/F meter or sensor is out of order, or the meter is not acting fast enough for quick A/F ratio changes if the carb is running out of fuel at WOT.
- Vibration damper is a new fluid damper, and TDC is checked
- Valve spring coil bind was checked during the head assembly
- Cam was degreed, checked today my memorandum of this rebuild and set it at 106 deg. Cam gear was straight up, not 110 deg like Lunati announces when straight up.
- Rotating parts, crank, rods, pistons professionally precision balanced.
- Fuel line, I am a little bit shamed to make a confession, but it's factory original
- Fuel pump, the high volume Carter M6903, is also relatively old. If I recall correctly it's from the beginning of the 90's and it was unused for many years before taking into service again.


Based on your feedback I'll concentrate on the fuel issue and at least the following improvements will be done:

- New 3/8" fuel line
- Fuel pick-up/sending unit sock, checked and replaced if needed or in any doubt of it
- Lifter preload adjusted, 3/8 to 1/2 turns, depending on if it starts making noise with less preload.
- Will test also .006 reluctor cap


What do you think this engine combination might be capable at 1/4 mile if it's pulling like it should?

My target is a low 12 or preferrably .01 under

Re: Charger with 440 won't pull and rev enough? [Re: AutoEngineer] #1236065
05/20/12 05:04 PM
05/20/12 05:04 PM
Joined: Feb 2005
Posts: 4,234
Prospect, PA
BSB67 Offline
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Not sure you are getting what is being said about fuel pressure. Its not throw money at it. Simply check the actual fuel pressure at the carb when the car is going through the traps. At your power level with a 3/8" line 5 psi is enough.

Re: Charger with 440 won't pull and rev enough? [Re: AutoEngineer] #1236066
05/20/12 07:07 PM
05/20/12 07:07 PM
Joined: Mar 2009
Posts: 2,359
Sydney,Australia
tex013 Offline
top fuel
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Sydney,Australia
looking at your jets seem a little low to me.
in comparison my 440+0.055 with a M1 plus 1" open spacer and 825 mighty demon is jetted F78,R92 and when i run a Prosystems 1000HP Holley based carb is F84,R92
i do race with an air plate sealed to a six pack scoop
motor is 10.78:1,258/258 solid flat tappet
3/8 line for my motor was good with a holley black 150 pump to mid 11.3's then needed -8 lines
good luck

Tex


New best ET 10.259@129.65 .
New best MPH 130.32
Finally fitted a solid cam,
stepped it up a bit more
3690lbs through the mufflers
New World block 3780lbs 10.278@130.80 . Wowser 10.253@130.24 footbraking from 1500rpm
Power by Tex's Automotive
Re: Charger with 440 won't pull and rev enough? [Re: tex013] #1236067
05/20/12 09:09 PM
05/20/12 09:09 PM
Joined: Jun 2005
Posts: 4,041
michigan woods
imfixinmopars426 Offline
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michigan woods
sounds stupid,BUT check the wiring to the dist.from the ecu. i have had the two wires switched around...dont ask,lol...and the engine acted strong down low,maybe to 3500-4000,and then laid flat.some of the stuff we have,has the wire connector cut off.others have had home made wiring,so...just check it for the fun of it...might just be it???? good luck,mike

Re: Charger with 440 won't pull and rev enough? [Re: imfixinmopars426] #1236068
05/20/12 11:23 PM
05/20/12 11:23 PM
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Shelby mi.
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JAKE68 Offline
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Shelby mi.
If your fuel curve is within what you say you have all the way down the track that is not a symptom of a bad o2 sensor!!! It would have been most likely all over the place. If you had any fuel delivery problem the o2 would have gone dead lean. It dose not mater how many jets are different to other motors in comparison to yours your a/f didnt show that there was a problem. Just saying.

Last edited by JAKE68; 05/21/12 11:58 AM.

JAKES AUTOMOTIVE
Re: Charger with 440 won't pull and rev enough? [Re: JAKE68] #1236069
05/21/12 12:36 AM
05/21/12 12:36 AM
Joined: Apr 2012
Posts: 136
Louisiana
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Red440 Offline
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Ditch the carter and get a holly blue or black pump,run at 7 pounds and also back off on the lifter pre load I have seen lifters that were not completely pumped when set and then were to tight when ran,and as Wise says check fuel pickup and line completely for any kinks or obstructions

Re: Charger with 440 won't pull and rev enough? [Re: Red440] #1236070
05/21/12 11:54 AM
05/21/12 11:54 AM
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Posts: 17,150
S.E. Michigan
ZIPPY Offline
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Quote:

If you had any fuel delivery problem the o2 would have gone dead lean. I dose not mater how many jets are different to other motors in comparison to yours your a/f didnt show that there was a problem. Just saying.







It might not be a bad idea to confirm the a/f readout is working correctly, though. Unfortunately that would probably mean installing it on another car for awhile?

Where is the lifter preload set?
Any chance it could be lifter pump up causing it


Rich H.





Re: Charger with 440 won't pull and rev enough? [Re: ZIPPY] #1236071
05/21/12 12:02 PM
05/21/12 12:02 PM
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Shelby mi.
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JAKE68 Offline
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Shelby mi.
Quote:

Quote:

If you had any fuel delivery problem the o2 would have gone dead lean. I dose not mater how many jets are different to other motors in comparison to yours your a/f didnt show that there was a problem. Just saying.







It might not be a bad idea to confirm the a/f readout is working correctly, though. Unfortunately that would probably mean installing it on another car for awhile?

Where is the lifter preload set?
Any chance it could be lifter pump up causing it


.
3/4 of a turn or .375 sounds tight to me for that. The only thing that he has not said yet is what the a/f ratio is for sure going down track and top end. If it is 12.2 it is not a fuel problem.


JAKES AUTOMOTIVE
Re: Charger with 440 won't pull and rev enough? [Re: JAKE68] #1236072
05/21/12 01:13 PM
05/21/12 01:13 PM
Joined: Jul 2008
Posts: 179
Up in the North and Far Away
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AutoEngineer Offline OP
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AutoEngineer  Offline OP
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Up in the North and Far Away
Hi guys

Will try get an other A/F meter for the next weekend to verify the AF readings.
At the moment I am suspicious for the meter more than anything else.

And for sure will also have to check the fuel line and the pick up for corrosion or anything else that could be clogging the fuel line. Will try also an other HP fuel pump, a brand new that has been sitting on shelf...

Lifter preload might be a little too tight. Tried to avoid a ticking noise that comes with too less preload, but can try to loose the preload gradually.

I am targeting to break the 12s barrier on the 1/4mile. Into our neighbourhood came last summer a big bad Chebby that's been terrorizing the streets of our village now for a too long time. It has been burning tire on every main street and corner

It's time to kick the a$$ of that chebby after having the Charger performing like it should with this combination

Re: Charger with 440 won't pull and rev enough? [Re: AutoEngineer] #1236073
05/21/12 01:54 PM
05/21/12 01:54 PM
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
Mr.Yuck Offline
Not enough dumb comments...yet
Mr.Yuck  Offline
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Posts: 24,562
Brookeville, Md
well you are losing at least 4 tenths at the 60 foot mark. You should be around the 1.65 60 foot. Now on to the rpm problem...I'd think if you had a fuel problem it would be ok thru 1st and maybe 2nd. From my experience when you have a poo poo pump it's at 3/4 track when you find out. Are you running it w/ an air cleaner assembly? If so remove it and run just the base plate. I'd think with that MPh you should be real low into the 12's and if you can pick up 2-3 mph maybe high 11's.


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