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-   -   Purple Cam (https://moparforums.com/forums/f81/purple-cam-14184/)

raycan2 02-06-2013 11:13 AM

Purple Cam
 
I got the cam out of the car {440} and found out it comes from Mopar.com What can you guys tell me about this cam here are the specs.
Is this a hot cam or not or can I go with somthing hotter.

P4120235AC Camshaft, Hydraulic, 284/284 Adv. Duration

Advertised Duration = 284/284
@ 0.050" = 241/241
O-Lap = 68
Center Line = 108
Lift = 0.484/0.484
Recom Spring = P3690933
Basic RPM = 2200 - 5900

Skwerly 02-06-2013 11:44 AM

That will depend on the rest of the engine. What have you done with the heads and such?

TVLynn 02-06-2013 01:13 PM

That cam design is probably 30 years old, still a good cam. there are better cams today. You need a 2500-2800 stall converter, 3.23 gear minimum. preferably 3.55 or 3.91

Gorts 5th 02-06-2013 01:33 PM

i can tell you this...Lunati
Advertised Duration (Int/Exh): 284/292
Duration @ .050 (Int/Exh): 242/252
----------------Gross Valve Lift (Int/Exh): .533/.552--------------
LSA/ICL: 110/106
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 2500-6600
Includes: Cam Only
look at the lift on this cam i think your 440 will appreciate the modern grind of this cam over the old school purple grind cam.
or this one.
Advertised Duration (Int/Exh): 276/284
Duration @ .050 (Int/Exh): 234/242
---------------------Gross Valve Lift (Int/Exh): .513/.533---------------
LSA/ICL: 110/106
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 2200-6400
Includes: Cam Only

PK1 02-06-2013 04:18 PM

Very good stick. And the technology fits the design nicely. You won't realize much improvement IMO if all else is stock with a new cam.

Is this the cam you wiped? If so there are better replacements!!

raycan2 02-06-2013 05:47 PM

yep
 

Originally Posted by PK1 (Post 97511)
Very good stick. And the technology fits the design nicely. You won't realize much improvement IMO if all else is stock with a new cam.

Is this the cam you wiped? If so there are better replacements!!

The cam I described is the one I wiped out and need to replace. I just dont know with what...

PURPLE HORONET 02-06-2013 09:15 PM

What wiped the cam out,, didnt up bend push rods also

blue 68 gts 02-06-2013 09:47 PM

Purple shaft cams are GARBAGE these days. STAY AWAY. Known for wiping lobes.

I run LUNATI CAMS.

Mr.4spd 02-07-2013 02:52 AM


Originally Posted by blue 68 gts (Post 97521)
Purple shaft cams are GARBAGE these days. STAY AWAY. Known for wiping lobes.

I run LUNATI CAMS.

Yeah, I wiped a .484 stick about 12 years ago. This is common? I assumed it was an improper break-in at the time. Do you suppose it's the cam itself or junk lifters that are the culprit?

Gorts 5th 02-07-2013 05:00 AM

Cam s are being wiped out for a lack of ZINC in the oil, and about 12 yrs ago they started to remove it this in-turn put a couple of cam makers out of bushiness.
What ever you do run a zinc additive in your oil.

raycan2 02-07-2013 06:13 AM

Yea it ate up the bottom of the # 6 lifter on the exhaust and bent the one right next to it, I talked to a mechanic and he said it looks like the rod jumped out of the lifter and caught the edge and bent it, I am thinking that was one problem no Zink....I replaced the lifter about 250 miles ago and now that i took out the 440 the lifter was about wiped out again...You can see the cam is not good and feel rough on that lobe.... So I am gonna have the block cleaned and every thing else checked now that its out.

Gorts 5th 02-07-2013 07:09 AM

You know for sure your cam lob is damaged unless it's reground it will just keep eating up lifters
your on the right path, getting a new cam will be the ticket the cams i posted are lunati the lift is awesome for mopar because of the long rods, the engine will perform even better.

raycan2 02-07-2013 10:26 AM

Gorts will it give me more HP that the cam I had before, Any of the cams you mentioned that is I am trying to learn the Cam side of things on how to read them and all...I had freind's tell me just take it to some one and let them do all the work, But if I do that I am not learning a thing...

PURPLE HORONET 02-07-2013 10:33 AM

To set it up correct you need to buy some adjustable rockers..

Gorts 5th 02-07-2013 11:41 AM

yes you should get more hp check this out....
this was originally posted by Chryco Psycho.
I keep getting asked the same ?s so I will try to explain the basic principals of cam design & selection. The cam is basically the heart of the engine and controls the power. It is also 1 of the least understood parts of the engine.
There are 4 parameters in the design of cams - duration, lift , overlap, & centerline.
1] duration - this is the most important aspect of the cam as it determines what rpm the cam works at , this is the # of degrees that the valve stays open measured in crankshaft rotation. When selecting a cam this is the first thing to consider determine what you use the engine for & be honest or you will be disappointed with the performance !!
This works as a guide & the numbers are approx as centerline, porting, roller cams etc. will vary the results a bit.
Advertised @.050 RPM
240 - 250* 200 - 210* idle - 4500
250 - 260* 210 - 220* idle - 5000
260 - 270* 220 - 230* 1300 - 5400
270 - 280* 230 - 240* 1500 - 5700
280 - 290* 240 - 250* 2200 - 6000
290 - 300* 250 - 260* 2700 - 6200
300 - 310* 260 - 270* 3000 - 6500
310 - 320* 270 - 280* 3500 - 7000+
The peak Hp will be reached approx 500 rpm before the max rpm & the peak torque will be reached approx 1500 rpm before max rpm, the other secret to making power is to match all the other components such as intakes, headers ,head work converters to work at the same rpm so the whole package works together, you will be disappointed if you match an intake rated for 4500 rpm max with a cam that starts working at 3500 rpm!!
2] lift - this is how far the valve is lifted from the seat, lift does not affect the rpm the engine works at but the more the better at a given duration , Mopar cams use a wider lifter so the valve can lift faster than other makes. UltraDyne , Hughes & Mopar all have cams designed to take advantage of the wider lifters Also the Mopar heads stop flowing more air or the valve becomes invisible to the air flow around .550 lift without port work.
3] overlap - this is the amount of degrees both of the valves are open at the same time & this is done to use the velocity of the exiting exhaust to help pull in the new air/ fuel mix this effect works better with higher rpm which is why the overlap increases with bigger cams, but the increase also hurts idle quailty & causes the lope when the engine is running. Larger headers will also hurt this effect by decreasing the velocity & resulting vacuum.
4] centerline - this is the least understood aspect of cam design & to over simplify the higher the # of degrees the longer & flatter the power band becomes [eg 115*] & the lower the # the shorter & more peaked the power band becomes [eg 106*] for example a 115 cam may give you 300 hp from 3500 - 5500 rpm with a peak of 375 hp where a 106* cam would give you 275 hp from 3500 -5500 rpm & a peak of 395 hp [these figures are arbitrarily made up] I prefer the long flat power band , it works well with the long mopar rods & gives pull everywhere but if you have ideal gearing & 5 speeds in the trans to decrease the rpm drop between shifts the car should run faster with a lower centerline cam.
Generally choosing a smaller cam will hurt you less than choosing a cam that is bigger than you need.

If you have more ??s , ask!!


he main reason I stick with Lunati is Harold , he was the one of the first to take advantage of the wider Mopar lifter & increase the ramp speed accordingly although I am sure Mopar engineers understood the advantages in the 50s when they designed the V8 engines . Harold started UltraDyne & I could see the advantage of using UltraDyne cams years ago , but UltraDyne went out of business & I printed their online catalog before it was removed from the internet . Hes was hired by Lunati at the time he closed his own business , Ulradyne . Since then many have copied him with Mopar specific grinds having more lift at the same duration . Most Comp Cams designs for Mopar are copied from the small block Chev, you can find the exact same grind in both the Mopar & small block sections although they are starting to change , the SBC has a very short rod ratio & needs a totally different cam than the Mopar , it is just lazy to copy the SBC design for Mopar . Harold has created a whole new series of cams for Lunati for all makes of engines which is sold as VooDoo as well most of the UntraDyne profiles can be found in the Lunati catalog still . There is a section around pg 185 with various lobe profiles in Hyd & Solid lobes specifically for the 904 lifter Mopars & AMC

Further to this is the Chev is a short rod engine with a 1.45 rod ratio
Mopar is typically in the 1.7 - 1.8 range with much longer rods .
This changes a number of things , @ both TDC & BTC the piston moves much slower & actually stops for a longer period of time this does 2 things it allows more time for complete burn of the fuel & moves away slower allowing more time for the pressure to work on the piston which results in increased torque & decreased fuel consumption ! If you have driven an older GM pick up you are lucky to get 9 MPG while a 440 can get into the teens & sometimes into the 20s , the best I have done so far is 24 mpg in a 440 Challenger on the highway & 512 " strokers pushing high teens on the highway even with dynoed stupid power .
The downside to long rod engines is the intake , the piston moves away slower so the engine tends to pull less hard on incoming air flow . Ever notice that the 440 Port is only slightly larger than the Chev small block while the 454 , 455 , 460 even the 351 boss have Huge intake ports ? The trick is velocity , by using a smaller port the air speed in the port is higher so the air flow is kept moving even when the valve is closed building pressure behind the valve & creating a mild supercharging effect . conversely the short rod engines pull air better so having a bigger port with more air available makes sense .
Back to the cam choice do you really think a cam designed for a short rod engine is ideal in a long rod engine ?

raycan2 02-07-2013 06:38 PM

Wow that opens up a whole new world to me...Thanx Gorts

Gorts 5th 02-08-2013 04:52 AM

Your welcome.
Yea me too, my next cam selection will be voo doo!

acerimmer 02-17-2021 12:24 PM

440 purple cam ID
 
Hi all, I'm trying to identify my Chrysler 440RB cam with solid lifters and can only find 2468639 on the tail end and SCH 58 on the shaft diameter at the distributer gear where the purple is. I measured the intake and exhaust lobe lift and got .474/.474 then cross referencing to the victory library it tells me it's a 280 deg. Hydraulic P4452993. This cam was purchased in the late 70's or early 80's and has solid lifters. Can anyone help?

Iowan 02-17-2021 01:00 PM

Ive got an engine book from 83-84 it doesn't list the number you have and only listed a hydraulic cam with 280 duration 4.74 lift #P4286631.
With the exception of the cheater cam mopar didn't offer a solid cam with less than .500 lift for a big block.

RacerHog 02-19-2021 07:37 AM

i'm Not finding that part number in my searches.... ??????

RBLowbucks 02-17-2024 08:11 PM

I'm a couple of years late to the party on this thread but just noticed it. The cam you mentioned is a purple stick and here is the info on it:
https://cimg2.ibsrv.net/gimg/moparfo...8b398a3367.jpg
https://cimg4.ibsrv.net/gimg/moparfo...d8c4b1e090.jpg


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