Re: VooDoo cam experience
[Re: Bob_Fromm]
#516746
11/05/09 06:59 PM
11/05/09 06:59 PM
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Joined: Feb 2003
Posts: 21,318 Manitoba, Canada
DaytonaTurbo
Too Many Posts
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Too Many Posts
Joined: Feb 2003
Posts: 21,318
Manitoba, Canada
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Quote:
Polling the Mopar group for feedback in their experience with the VooDoo cams. Mine is not so satisfying.... Built a new 440 over the winter, 10.2 real cc'd compression, 440 Source heads, CH4B intake, 800 Thunder carb. 60303 VooDoo degree'd in at 105 1966 Coronet sedan 4 speed 3.91's Broken in properly. The engine (cam) is a pig on the bottom, comes on about 2500rpm and then seems to peak at approx. 4k and falls on it's face. A friend also installed same cam (yes degree'd in at the reccomended 106) in a fairly fresh 440 (10.3:1 cc's compression) 727 auto car with 3.23's and it acts/repsonds about the same way, pig on the bottom (car hardly brake torque the tires loose) comes on approx. 2500 rpm and then falls on it's face around 4k. We are pretty disappointed. Did much research for 9 months or more, read the limited feedback that was available and thought we had a winner here. You would think (and from previous experience) that a fresh 440 (both of ours) would roast the tires at will. What gives? I will be puling mine out and replacing it this winter. Not sure with what yet. Anyway other shared experiences would be appreciated...
I run the 60303 cam in my low CR 440 and it does well. Just ask the kid at work who was grin from ear to ear on saturday when I drove my car to work and did a hard launch(no brakes, just throttle to the floor) right in front of him and left a wall of smoke behind me. I too am running 440source heads w/ the valve springs that came with them. Cheapie headers and for now a stock spreadbore dual plane intake with a thermoquad. Stock 727, stock converter and suregrip w/ 3.55 gears. When I nail the throttle hard from a stop, it breaks both rear tires loose and the back end goes sideways. I would say peak torq is 4000rpm with this cam in my combo, but it still pulls good to 5500. I would expect better top end and mid-range from your 10:1 440.
I do find mine loves a ton of initial ignition advance, the more the better. But I attributed that to having this cam with a low CR, not to the cam design itself. I think my combo with a 3000rpm converter and 4.10's would really make it haul in the bottom end and that's in the plans.
If my low CR 440 can do well with this cam, then if your 10:1 440 isn't a ground-pounder with this cam something is wrong, and I doubt it's the cam. FWIW I spent a fair amount of time tinkering with the distributor and I know it's not ideal yet. Also I tune with a wideband o2.
Have you done a compression check? Where are your numbers at?
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Re: VooDoo cam experience
[Re: DaytonaTurbo]
#516747
11/05/09 08:08 PM
11/05/09 08:08 PM
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Joined: Apr 2006
Posts: 3,675 Akron, Ohio U.S.A.
roadhazard
master
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Joined: Apr 2006
Posts: 3,675
Akron, Ohio U.S.A.
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I do find mine loves a ton of initial ignition advance, the more the better. But I attributed that to having this cam with a low CR, not to the cam design itself. I think my combo with a 3000rpm converter and 4.10's would really make it haul in the bottom end and that's in the plans. I do not run this cam, however initial timing is critical. I had issues with my car not leaving properly and slow 60' times (high 1.4's - low 1.5's) for waaay toooo long! After beating my head against the wall I limited the advance in the distributor and put 20* initial timing in it and 37* total (you may require diffrent). Wow what a difference Now my best 60' is 1.389 with consistant 1.40's. If it falls off after 4,000 rpm then you might have a fuel delivery problem. My car would hardly lift the tires 3" before, now look!
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Re: VooDoo cam experience
[Re: chrisf]
#516750
11/05/09 09:10 PM
11/05/09 09:10 PM
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Joined: Mar 2008
Posts: 5,746 Ontario, Canada
Dodgem
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master
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Posts: 5,746
Ontario, Canada
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That is a medium mild cam. my guess first off would be vacuum advance hooked up to manifold vacuum. First off vacuum advance should never be hooked up till all your other tuning is done. my second guess is stock distributor springs not allowing what little mechanical advance to come on till 3500 or so. so say this is the first too problems say you have 35 total but that total includes 20 deg of manifold vacuum and the 20 deg of mechanical is not all in till 3500. So that puts you pre start up initial at -5 deg. At WOT there is no vacuum so when you floor it at 2000 rpm the vacuum advance is gone and if all you have is a slow curve mechanical left you are probably at 5 deg of advance or so and that is so slow. then as your rpms increase to past 4000 the motor needs advance but you may be at 15 deg of total advance so no go either. I could be wrong but I seen this lots!! I would unhook and plug vacuum. set total to 38 deg with lighter advance springs having it all in by 2000 to 2200. when ypu have it all tuned in right see how it works. then and only then vacuum goes to the ported vacuum and any pinging is tuned out of the vacuum pot with a 3/32 allen wrench (in through vacuum pot) going counter clockwise till you have no ping under all types of driving!
Last edited by Dodgem; 11/05/09 09:12 PM.
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Re: VooDoo cam experience
[Re: Chilort]
#516752
11/05/09 11:35 PM
11/05/09 11:35 PM
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Joined: Jun 2004
Posts: 6,780 Alabama
Mopar-Al
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master
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Posts: 6,780
Alabama
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Kinda sounds like you did your degreeing on the exhaust and not the intake lobe maybe Doesn't the voodoos have a split in/ex centerline? Like 106 intake 110 exhaust. Just wondering
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Re: VooDoo cam experience
[Re: Chilort]
#516754
11/06/09 01:20 AM
11/06/09 01:20 AM
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Joined: Feb 2003
Posts: 21,318 Manitoba, Canada
DaytonaTurbo
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Too Many Posts
Joined: Feb 2003
Posts: 21,318
Manitoba, Canada
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Quote:
DaytonaTurbo, how much initial are you running?
I'm running as much initial advance as I could before the engine started to fight against the starter. Honestly I don't know what the actual amount is. When I first fired the motor after the cam swap I baselined it to 12* just to get it running. Then I upped it to 16 and from there I put the timing light away and just tweaked it by hand until I got as much as I could before it would resist being turned over. Should have checked it afterwards but it runs well so I've left it. But then I've also been running it on pump 94 octane so I'm sure it would tolerate all the timing in the world!
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Re: VooDoo cam experience
[Re: DaytonaTurbo]
#516755
11/06/09 01:26 AM
11/06/09 01:26 AM
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Joined: Nov 2003
Posts: 36,040 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
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Posts: 36,040
Lincoln Nebraska
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Hello Bob. I'd see what your (cranking) compression is for a baseline. then as said "timing"
live every 24 hour block of time like it's your last day on earth
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Re: VooDoo cam experience
[Re: ademon]
#516757
11/06/09 09:18 AM
11/06/09 09:18 AM
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Joined: Jan 2003
Posts: 16,123 Grand Haven, MI
patrick
I Live Here
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I Live Here
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Posts: 16,123
Grand Haven, MI
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what does the rest of your ignition system look like? maybe it's a problem with weak spark/voltage drop ahead of the coil?
1976 Spinnaker White Plymouth Duster, /6 A833OD 1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!*** 2011 Toxic Orange Dodge Charger R/T 2017 Grand Cherokee Overland 2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)
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Re: VooDoo cam experience
[Re: Bob_Fromm]
#516758
11/06/09 09:57 AM
11/06/09 09:57 AM
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Joined: Mar 2008
Posts: 5,746 Ontario, Canada
Dodgem
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Ontario, Canada
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That is strange they should have lots of grunt from 2000 to 5600 set up like that. Did you check the damper to see if timing marks are in faze? (they are well know for outer ring moving but not likely on two differnt cars.) I too would like to see a compression test. Poor spark maybe?? Did the same guy degree both cams and does he have lots of experience?? It is really strange as you have two engines both performing poorly in two different cars that would have two different fuel systems, two ignition systems two different torque converters and so on but only one common denominator the cam and maybe who degreed it and how it was degreed?? both should work great at 106 or 105 and that is not enough difference to feel?? Now if the exhaust was degreed at 105 the intake would be 115 and that would make them lazy @$$ motors??
Last edited by Dodgem; 11/06/09 10:03 AM.
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Re: VooDoo cam experience
[Re: RobX4406]
#516762
11/06/09 07:38 PM
11/06/09 07:38 PM
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Joined: Apr 2006
Posts: 3,675 Akron, Ohio U.S.A.
roadhazard
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Akron, Ohio U.S.A.
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Quote:
Timing being all in by 2K doesn't mean squat if you don't have enough initial. how's that going to work if the distributor has 24-26 mechanical... not well with your set up.
Low intial will make an engine really lazy down low, poor throttle response, dirty idle. Probably needs a minimum of 15-18 initial and the rest in mechanical.
I'd double check the cam timing too..
I was even able to close down my throttle plates after I put some INITIAL Timing in it and REALLY CLEAN UP MY IDLE!
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