mopar performance cam specs change?

-
jammied

jammied

Well-Known Member
Joined
Oct 16, 2015
Messages
237
Reaction score
92
Location
wyoming
I am in the process of putting my 340 back together it had a rounded cam lobe. So going through the list of mopar performance cam shafts I chose #p4452761 all of the specs I found online stated a duration @.050 of 228/231 and a 110 centerline. I received the cam today and it didn't have a cam card with it just a generic sheet listing all the cams. The sheet is listing this cam @.050 220/224 and a 108 centerline. Now I'm strongly considering sending the cam back as it is clearly not what it is advertised as. Did opar change the grind and not the info on their site? The biggest reason I chose this cam is the lift and duration because the 340 is getting magnum heads so the lift should increase to .480/.485.
 
It so appears through these tired eyes and a small screen that all the small cam specs changed. If you do send it back, I would so include a letter of complaint. Custom cams are inexpensive and can be done to copy the MP cam in a way as not to cause a legal stir.

Call up any cam grinder.
 
Not small block but I just got my 590 cam in the mail, same lift and duration but ground on a 104 instead of 106
 
Perhaps you have the specs for a 1.6 rocker ratio Rocker Arm? A .450 cam with 1.5 rockers will have .480 lift with 1.6 rockers.

Bob
 
Something awfully screwy is going on around here.... (Elmer Fudd voice...)
 
rgp266 correct the factory lift #'s are for 1.5 rockers and the magnum head rockers are 1.6 so the lift should be .480/.485 with the magnum rockers and should make the valves think the cam has more aggressive lobes.

lol yeah something is awfully screwy!! Not sure what to believe now.

Guess maybe I will just keep it and throw it in on a 106 intake center line. Kinda want to get this put together over the weekend
 
Tell ya. Seems like everytime I hear MP mentioned in the last 20 years, it's as if "they" are intentionally thwarting Mopar lovers from being successful.
 
They don't care about the old engines anymore. Haven't it at least a decade. Send it back and get credit on something else.
 
hmmmm well if the sheet they sent with the cam is correct its not the cam I ordered or is false advertising. 2 different cam profiles there! makes wonder what one they sent me?

Any one know a good custom cam grinder? and what a copy of the original would cost?
 
Call bullet and ask for Kirk,awesome guy and he specd me out a cam very similar to the MP grind with more aggressive lobes, came out to be $225 plus $20 shipping for a solid cam.... That's without lifters as well
 
Thanks I will do some calling around. just bums me out cant seem to find a off the shelf cam close to what this one is suppose to be. All of them I found have way more lift than I'm looking for with the 1.6 rocker ratio. I would like to stay in the .480-.490 lift range with duration @.050 in the area of 230
 
Call Hughes Engines and ask about their cams, they've ran hard in everything I've put them in. I haven't ran a MP cam in over 20 years as I feel there are much better cam designs on the market.
 
Mopar cams are old and outdated leave that thing on the shelf..MUCH better cams out there to choose from..
 
well yeah there is more than one way to skin a cat so to speak and I have nothing against hughes. But .550 lift is a lot!! stock magnum heads kinda start falling off and flatting out around the .500 lift. Just was looking for a cam that kept the valves open in the sweet spot of the magnums to keep the volumetric efficiency of the engine up. Now if I were going with ported or higher flowing heads The lunati voodoo series looks tempting.

I do appreciate your input and opinion.

Just was taken by surprise when the spec sheet said it was smaller duration @.050 then what is advertised. Crower has some grinds pretty similar to the MP cam that I was hoping to get. But still have more lift so I would either havto rework my current J heads or go tear apart the x head engine and rework those heads. lol I'm on a budget and have a fresh set of magnums
 
Hughes has smaller cams, call and talk to Dave and see what he recommends. In reality your valve spends much more time at the mid lifts than max lift.
 
oh ok yeah I remember hughes use to make smaller lift cams that still made 400hp+ without going over .500 lift on a 340. I also use to have a formula to calculate the open time of certain lift cams. There really on a proper ground cam and stock heads to ever go above .500 lift. But at any rate I will contact hughes and see if they still do the grinds they use to have on their website
 
Very true! For a low lifting cam, focus on the valve job and how well it flows. After .450, the port has more to do with flow. Until then, it's all in the valve and how well the valve itself is, the seat and it's angles.

Sorry, $225 for a short solid cam only from Bullet is a price braker for me. Way to high.
 
jammied said:
hmmmm well if the sheet they sent with the cam is correct its not the cam I ordered or is false advertising. 2 different cam profiles there! makes wonder what one they sent me?

Any one know a good custom cam grinder? and what a copy of the original would cost?
Click to expand...


Dave Crower also did a nice custom cam for my ex's slant for her Dart. She's happy with it. He was good to deal with...
 
krazykuda said:
Dave Crower also did a nice custom cam for my ex's slant for her Dart. She's happy with it. He was good to deal with...
Click to expand...

He has some really nice sbm grinds. Call & ask,the online or paper cataloging only lists a few.
 
I just noticed that the green sheet lists the cam P4452761,but the white sheet uses that part number as a kit. The cam in kit P4452761 is 4452760.
The cam no P4452760 does not appear on the green sheet.
The two different cams have the same advertised numbers, but different 050 numbers and LDAs.
If that is correct, it would be easy for the parts person to screw up
Or it could be typos
Confusing to be sure, and if the cam goes in as a 220/108 and you are expecting it to run as a 228/110, you may well be disappointed.
 
stroked340 said:
Mopar cams are old and outdated leave that thing on the shelf..MUCH better cams out there to choose from..
Click to expand...
I agree. The aftermarket designs have computer aided profies with faster lobes. My current favorite cam is Comp's magnum muscle 268AH-10 for a relatively stock LA engine with 9.2 or higher compression. A good bowl porting and three angle valve seats on stock heads is worth the effort and money. My shop claimed the porting is worth about 20-25 cfm.
 
Last edited:
AJ/FormS said:
I just noticed that the green sheet lists the cam P4452761,but the white sheet uses that part number as a kit. The cam in kit P4452761 is 4452760.
The cam no P4452760 does not appear on the green sheet.
The two different cams have the same advertised numbers, but different 050 numbers and LDAs.
If that is correct, it would be easy for the parts person to screw up
Or it could be typos
Confusing to be sure, and if the cam goes in as a 220/108 and you are expecting it to run as a 228/110, you may well be disappointed.
Click to expand...
I noticed that too? Just use the "kit" number P4452761. Good cam but very old design.
 
A [email protected] hyd cam that’s user friendly and easy on parts isn’t going to have [email protected].
That’s just BS info.

The 220 number might be correct...... but even then, I doubt the advertised duration is taken at .006.

A fairly recent design Howard’s fast rate .904 hyd lobe is [email protected], [email protected]...... but it’s .506 lift.

20+ year old MP grinds aren’t going have that kind of area...... and definitely not more area.
 
Last edited:
You must log in or register to reply here.
-

Back
Top