MP purple camshaft

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sbh126

sbh126

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My machine shop told me to go with kb237 pistons and a MP purple camshaft for my 440. Any opinions on these? I'd like a little more info on what cam I need. Hydraulic, mechenical, What duration. So on and so forth. I need something streetable but I want it a little choppy. Suggestions?
 
I'm running 237's and an MP 280/.474 cam. Plenty streetable with some chop. It's got the shake and vibration at idle and is happy with an 850dp on top. The .509 is a couple steps up from that one. Course, others are going to say there are modern grinds that are better than any of these in that range.

Exhaust idle clip here: http://youtu.be/BUi1Gk_NSm8 and action clip below.
 
In the case of modern grinds, they ofer a quicker ramp rate which is nice, but also not allways needed. It's also more wear/stress on the springs and valve train. The difference is splitting hairs, but it is true.

The MP cams may have been designed 30+ years ago, but the still perform as intended and will run the time. There ramp rate isn't as steep as some modern cams but stepper than the normal grinds.

FYI Comp Cams XE line is not a high rate of lift cam. You need to move up from the XE line to even get close.

Others complain about the MP cams in many ways. I have had no problems with them at all ever not once and I have sevral cams by them. Every manufacturer has had an issue with there sticks at one time or another. Not just the MP units. Don't beileve the hype. Take your time on breaking in a cam, do it right!
 
Rumble... The XEs are a fast rate. Just not the fastest rate for a .904 lifter...
I dont think I'd run an MP cam but not just because IMO you are losing out on benefits a modern cam gives, but also MPs quality just plain sucks.
 
Sorry Moper, I just don't by it. While quicker than last decades cam rates, they still fall shy. I do agree that a good split pattern cam will perform better in most cases.
 
Well, the way I read your post, you're saying the Comps "are not fast rate". I think we disagree on what we individually consider a "fast rate" of lift. My position is compared to the MP lobes, they are a fastER rate even tho they are designed for the smaller diameter lifter. They certainly are not the fastest rate for the .904, although the XE/HL versions are a bit closer to "as fast as you can get" with a .904.
 
I'm in need of a good cam also, for a 383.... Is the MP 509 to much for a 383? I'm going through the whole engine, so budget wise I want to keep costs as low as possible right now.. My main concern is the biggest cam my 383 can handle without having to go with high dollar adjustable rockers..
 
moper said:
Well, the way I read your post, you're saying the Comps "are not fast rate". I think we disagree on what we individually consider a "fast rate" of lift. My position is compared to the MP lobes, they are a fastER rate even tho they are designed for the smaller diameter lifter. They certainly are not the fastest rate for the .904, although the XE/HL versions are a bit closer to "as fast as you can get" with a .904.
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I agree with this.

EL5DEMON340 said:
Comps MM lobes are .904 FAST.
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R U sure about that?
Not that I'm going to argue. Isn't there a faster rate of lift than the MM? I know they (Comp) have a MoPar only, max rate of lift cam lobe for the big block engines and HEMI only cam lobes.

greenhornet said:
I'm in need of a good cam also, for a 383.... Is the MP 509 to much for a 383? I'm going through the whole engine, so budget wise I want to keep costs as low as possible right now.. My main concern is the biggest cam my 383 can handle without having to go with high dollar adjustable rockers..
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The cams duration is something that should work inconcert wit the cars weight, rear gear and tire size, engine specs with the thought of it's intended purpose.

This may also require a new stall converter for best results or a dog off the line you'll have.

IMO, it is best to start up a thread for this questiopn. Currently, it is to vauge and it will need more infomation like I mention in the first paragraph.
 
why guys waste their money on mopar performance cams is beyond me. 1970 technology. In my opinion if your engine builder says to go a MP cam they are behind the times, i would sugest another builder.

junk.
 
I'm going to match everything up, I was just wanting a general idea how much cam a 383 can handle before it requires adjustable rockers..
 
chrisf said:
why guys waste their money on mopar performance cams is beyond me.
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1, they still work and as intended. If you ever read the "Tips" section in the old catologs, your picture would be more complete.

2. single pattern cams are not bad cams. Split patteren cams are (IMO) better, but notallways perfect ethier for a given application.


1970 technology.
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Still working


In my opinion if your engine builder says to go a MP cam they are behind the times, i would sugest another builder.
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Just wondering, what do you do for a living?
 
greenhornet said:
I'm in need of a good cam also, for a 383.... Is the MP 509 to much for a 383? I'm going through the whole engine, so budget wise I want to keep costs as low as possible right now.. My main concern is the biggest cam my 383 can handle without having to go with high dollar adjustable rockers..
Click to expand...

Greenhornet, I'm running a 509 cam in my 383 with no problems. A couple of years ago I ran a 383 and a 509 with the factory stamped steel rockers again with no problems. Then one day I decided to measure the actual lift at the valve so rigged up an adjustable lifter set at 0 lash and a mag base dial indicator and guess what I found. Instead of having .509" lift at the valve I was getting .020" less (if memory serves) which was pretty close to the rumours I'd been hearing about the accuracy of the stamped steel rockers hence the reason I've stuck with adjustable rockers for hydraulic cams. The present 383 is having the comp roller rockers replaced with Hughes next month mostly because of lite gauling activity between the comps and rocker shaft. But back to your question, the biggest concern about using the 509 cam in a 383 is piston to valve head clearance which can be very tight if the pistons are flat top and 0 deck, valve relief pistons are required.

I don't care if the 509 is "old school", it's trouble free, it sounds great and it goes like snoot and I've used it in 5 different builds over the years. So I might go .2-.4 faster in the quarter with someone else's cam, I don't really care cuss generally I like to dance with who I brung.:-D
 
I don't care if the 509 is "old school", it's trouble free, it sounds great and it goes like snoot and I've used it in 5 different builds. So I might go .2-.4 faster in the quarter with someone else's cam, I don't really care cuss generally I like to dance with who I brung.:iconbigg:

Thanks for the info... Some people try and keep re-inventing the wheel, It's like most of the gear drive craze, most guys I know have went back to the ole' tried and true double roller...
 
greenhornet said:
I don't care if the 509 is "old school", it's trouble free, it sounds great and it goes like snoot and I've used it in 5 different builds. So I might go .2-.4 faster in the quarter with someone else's cam, I don't really care cuss generally I like to dance with who I brung.:iconbigg:

Thanks for the info... Some people try and keep re-inventing the wheel, It's like most of the gear drive craze, most guys I know have went back to the ole' tried and true double roller...
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Funny you should mention, I ran a gear drive (generally refered to as the poor mans blower) on a 440 10 yrs back and got tired of people asking "If I wanted cheeze with that whine".:-D
 
demon seed said:
Funny you should mention, I ran a gear drive (generally refered to as the poor mans blower) on a 440 10 yrs back and got tired of people asking "If I wanted cheeze with that whine".:-D
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Did anyone offer you any power steering fluid or a new pump???
 
ive never run a purple cam but considered it.i decided not to when i had a 280/474 profiled at schneider cams and found that it was actually 232@ 50 rather than the advertised [email protected] they do not come parkerized and i was worried about failure on break in....however ive talked to a few people that run this grind and really like it.
 
sbh126 said:
My machine shop told me to go with kb237 pistons and a MP purple camshaft for my 440. Any opinions on these? I'd like a little more info on what cam I need. Hydraulic, mechenical, What duration. So on and so forth. I need something streetable but I want it a little choppy. Suggestions?
Click to expand...
The KB237's are fine...they will get you in the 10:1 to 10.43:1 CR range...I need to know what gear and stall you are running before I would suggest a cam for you...never used the MP purple cams but alot of people do...give us your gear and stall and we can give you more selections..take care...8)
 
The .509 can be a good cam IF YOUR COMBO IS RIGHT!. You need minimum of 10.1 compression, at least a 3000 convertor and at least 3:91 gears, otherwise it will be a dog on the bottom end. Consider the MP .528 mechanical. Better manners and will pull to a higher RPM.
 
EL5DEMON340 said:
Comps MM lobes are .904 FAST.
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Yes, but the MM lobes are solid flat tappets and we're talking hydraulics. Personally I will use a shelf grind hydraulic in every engine I need to use one in. Some of what I'd call my best packages use Crane hydraulics whose designs are at least 25 years old. I even bought a couple when they closed just so I'd have some...lol. A favorite is the H302-2, which is a hydraulic that doesnt need a ton of spring, is stock quiet, idles much better, and will pull like the .509. So I wont say old is bad.
The right cam will make the power you want. If the engine wants a large duration, short lift cam, the .509s a valid choice. You just have to make sure you degree it because more than likely you'll need to move it to get the installed centerline right. The last one I used I had to use offset keys on the crank AND cam to get it to what MP recommended. It was ground 9° retarded. MP's quality control sucks.
If I want bigger power I'll go solid flat tappet and custom, but even on those I'm more likely to use the .875 profile SQ, FL, or -12/-13 lobes. My engines need to idle, and hude spring pressures that the .904 lobes mandate mean higher idle speeds and greter chance of problems. If you really need to make power and it's a serious effort, solid roller is the right way to do it.
 
bremereric said:
The KB237's are fine...they will get you in the 10:1 to 10.43:1 CR range...I need to know what gear and stall you are running before I would suggest a cam for you...never used the MP purple cams but alot of people do...give us your gear and stall and we can give you more selections..take care...8)
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I have 3.55 gears and an overdrive 4 speed.
 
If I do go with the MP 509 how streetable would it be? What head would compliment this cam and what other parts would I need? Will I be ok with stock rockers or do I need to upgrade? If so what would you recomend? I have a fresh machined block, $5000, and the original parts from the 440. I'd like to use the stock crank and rods to save some $. I guess what I'm asking is where is my money best spent?
 
if it were me i would call hughes or look at thier web site hughesengines.com they have a far better product than most on the market for mopars
 
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