Mopar Purple Cam Comparison

[my64dart]

Hi Again,
   I posted earliar about building a 12 second,  383  Dart. I was recomended to use a Mopar Performance cam. Its the hydrualic 284*/284* duration    484/484 lift cam     Dur@ .050 = 241*/241*  centerline =114
 rpm range of 2200 - 5900
  Question is I also see a mechanical lifter cam with almost the same numbers but has a higher rpm rating of 2400 - 6600  Its numbers are 284*/284* duration   .528/.528 lift    dur@ .050 = 241*/241*  centerline=112* 
 Would these two cams have similar driving & performance characteristics? I know that the solids need to be adjusted once in a while but other then that would they be a good choice to use. So far I've decided on using KB400 pistons & Eddy heads for 10.0 compression.  I'm having a 3:91 ring & pinion installed & a torque converter not quite sure yet on the stall. Any suggestions here for which cam & stall speed combitation will work good together?
       Thank You

[383man]

The .528-284 cam is a nice cam and should work good in your combo.   I ran a 383 a few years ago in my sons Dart and used the old MP .484 cam on a 108 LSA. I installed it on a 104 centerline and it had nice low end.   Worked very good for me.   Its my sons green Dart in the sig. Now it has a 400 but the 383 was a bone stock shortblock that  I milled the stock 452 heads for 9.6 comp.  The heads were midly pocket ported and that was all they had done to them.   It had 3.91's and a Turbo Action tight 10" 3000 convertor.  Performer RPM intake and 750 DP.   Ran 12.31 @ 110 best.  It had a nice little lope in the idle and drove great. Some people dont like the old MP .484 but I love it.  You just have to use it in the right combo.  But the 528 is like a solid version od the old .484 as they both have the same advertised duration.   Ron

[Tom1951]

The only complaint I have with the MP cams is they use the cheapest vendors to grind them. I admit to being an ole fart and I remember from my early hot rod years that Racer Brown  was the main designer of the Mopar cams. Here is some food for though. Racer is still in business and custom grinds each cam with a lobe seperation and lobe centerline to match your combo. The MP284 was originally a SSH-25 238@050,485, the MP284 solid is a ST-15 240@050, 517, a step above those is the ST-21, 254@050, 520. Also Racer and FBO both have a stash of the good Johnson lifters. Tom

[dodgee]

hi, i have 284/484 purple cam in my 440 69 cuda 2800 stall eddy heads,schummacher headers , 750dp ,dual plane intake , 3.91 sure-grip , full street trim so far 12.1  1/4 mile and there is still more left. off season i am putting EDGE 3400-3600 converter, 2" maddog headers and 850 proform race carb. just hang on and enjoy the ride.

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[bentwheel43]

Man I like that Cuda whats the 60ft. on that thing, is it for the street.     

[MoPar_474]

I have experience with both of these cams in my 73 Duster street car, except with a 440, so hopefully i can help you out. I had the .484 hydralic in the motor first- it ran good, 12.20's-12.40's depending on the conditions, slightly lumpy idle/sounded good/performed good. BUT....after about a year performance started to deteriorate and one day I was driving and the engine started to missfire/pop and after tearing into it I found a wiped out lobe on the camshaft. So.....I went and bought the .528 mechanical purple shaft, got the right size pushrods and adjustable rockers and installed it. The idle quality was much smoother with this cam which was ironic being that it is actually larger, but it being a mechanical lifter you really cant compare it to the hydralic as far as the advertised specs. But the throttle response was greatly improved over the hydralic and it seemed to perform a hell of alot better than the hydralic as well. I was really impressed with the amount of low end torque gained with the swap-and it pulled hard to 6,000rpm as well. But to make a long story short I never made it to the track to see if it ran any faster because after not even a month it wiped out 7 lobes on the cam!

So, after losing lobes on 2 mopar purple shaft cams my advice to you is to NOT use them in your engine. My case is not the first I've heard about the quality of these cams being poor- alot of guys are having problems with them it seems. And it sucks because they definetly perform good, its just whatever they are making them out of is of a poor quality metal and they just don't last. I'm not saying that all of the cams are bad-I had a .509 hydralic in another car with no problems at all, but after what I just went through I'll never use a purple shaft cam again in any car. Thats just my .02 -hope I could help and prevent someone from making the same mistake that I did.

[bOb shingler]

may i suggest that folks use moly lube on the lobes and bottom of the lifters and then pour the can a juice into the crankcase and everything should go well from there on out. remember not to keep your rpm's at or above 2000 but to not let them get below 2000 and rev the motor up to keep the oil slinging out towards the cam lobes for 10 to 20 minutes.

[Tom1951]

Bob from Bob Built Engines is right on. Use moly during assembly and add a bottle of GM's EOS Engine Oil Supplement to you diesel grade oil during break in. We need to use a diesel grade oil now with our flat tappet cams because the regular oils and synthetics have eliminated the anti wear and high preassure lubs that kept our motors alive. All the new motors now have rollers in them.

[MoPar_474]

I aggree, you should definetly coat the cam/lifters generously with cam lube and follow the proper break-in procedures when starting an engine for the first time....which is what I have always done with all of the motors I have ever built for myself and for others. But with regaurd to my own personal experience, in the last 8 years I've assembled about 10 engines and the only two cams that have ever gone bad on me just happen to be the Mopar Purple Shafts, and I do not believe that it is a coincidence. With what I and countless others have encountered, I would have to say that there must be some problems with these cams as far as what they are made of and their quality. I have used Ultradyne and Comp Cams in the past with absolutely no problems and am very satisfied with their products. As far as the Mopar Cams, 2 out of 3 went bad for me and thats enough to make me never want to use them again.

[Mopar451]

i have used 4 diffrt. purple cams and never had a problem you have to use a moly assembly lube and with the solid cams i run with out the inner spring for break in but you need to check for the right spring pressure and make sure the retainer is not touching the valve guide.

[my64dart]

Hi,
  Thanks for all the input on the Purple camshafts. I think I'll try to find a similar grind in the Competition Cams brand. The last thing I need is to have brand new parts fail on me. Comp.Cams has a solid lifter (Magnum) cam thats 282 duration  .495 lift   236 duration @ .050   Operating range from 2500 to 5800 rpm.  This might be just what I'm look'n for.
     Thanks Again For All The Input

[7secondstreeter]

hello,i used purple shafts for years & had no problems until a couple of years ago i built a pretty hot 340 for a cust.i used the 508-292 purple shaft kit,comp springs,retainers & clips,i have built alot of mopars,everything is always double checked,including correct spring height,lifter preload,etc.i always use the G.M. E.O.S,it ate 2 mopar cams,i called mopar,they sent me a new cam kit[no charge],i sold it and installed a comp cam,and had no more problems,the dart is still kicken butt.i havent used a mopar cam since,just my input

[StripeHOG]

didn't ultradyne get bought out by another company??

[dusterdarryl]

iv got a purple shaft still new in its box, its a 533" 320 add duration  P-4529318. its a cam & lifter package with matching comp valve springs, sounds like I shouldnt use it, which would be a shame coz it would work well in a street 440 I have,... on another post here you guys are sayin that the orange box module are no good too.......  sounds like this MoPar stuff is not all its been cracked up to be for all these years. Im a bit disalutioned now

[Cudadust]

I have changed out two Mopar cams recently brcausr of performance and driveability issues and would not recommend their use.  Hughes, Straight Line Performance cams replaced the Mopar cams and both provided better performance in all RPM ranges.

[my64dart]

Hi,
  I just wanted to thank everybody for there input on the Mopar cams. This is the kind of information we can all use to save ourselves a lot of aggravation & money. I also learned quite a bit about the motor oils to use for breaking in a fresh motor. This is great information for everybody to use.
       Thanks Again

[mrspeeddemon]

didn't ultradyne get bought out by another company??

I think that all of Ultradyne's grinds became Crane Voodoo lineup, one of the head cam grinders from Utradyne went to Crane and took all of the grinds with him- Thats what I've heard anyways- don't know if its true

Also I've never tried a Purple shaft, I just thought that they could maybe figure out some new grinds in the last 20 years- since everything else in the industry has progressed with new technology! I like Comp Xtreme Energy line- try the Mopar high lift xtreme- made just for us Mopa-dopes!

[kenny crawford]

Ultradyne is owned by bullet cams now.

[gsmagnum]

Ultradyne is owned by bullet cams now.

The guy who was responsible for Ultradyne cams ended up at Lunati and designed thier Voodoo grinds.

[shoebox1.1]

i really wanted to run the 590 solid someday but im not going to just because of threads like this!   this isnt the 1st time or last that several folks tell stories of mopar lobes going to file 13!    as big corperate DCX is there--- its all about the money.. cheap cheap cheap.  lowest bidder. if comp cams did this THEY WOULD HAVE NO BUISNESS!!    mopar is in it for the DCX pockets not  to produce good flat tappet cams!     i wish the old ultradyne  solids were around..  like the muskle motors guys used to push..    tight lash 904 cams.   GO WITH THE COMP 236 CAM   it works!

[dusterdarryl]

i really wanted to run the 590 solid someday but im not going to just because of threads like this!   this isnt the 1st time or last that several folks tell stories of mopar lobes going to file 13!    as big corperate DCX is there--- its all about the money.. cheap cheap cheap.  lowest bidder. if comp cams did this THEY WOULD HAVE NO BUISNESS!!    mopar is in it for the DCX pockets not  to produce good flat tappet cams!     i wish the old ultradyne  solids were around..  like the muskle motors guys used to push..    tight lash 904 cams.   GO WITH THE COMP 236 CAM   it works!

         "Here Here!" i agree fully, after all we are "MoPar" guys arnt we & if we cant use the "MoPar" product even tho the designs are good then do we take a the "MoPar" signs & decals of our cars? seems a shame to do that.  then MoPar will become nothing & we can be like the GM guys(Oh my pontiac is better than your cheby) & jus call our cars dodges & plymouths because we all would use aftermarket parts that differ from each other instead of the common" MoPar" bond we have. (oh my plymouth is better than your dodge because...) we all like to fly the pentastar but if its products are s*#t then thats very sad for our hobby