440 resto cam advice

[don340-4]

anyone know why a mp 115 centerline cam comes in at 111 installed at 0 setting? Im rebuilding my 440 using the 268/284 115 centerline cam #p4452783 & the mp #p5249268 timing chain set, when i use the 4 degree retard mark it comes in at 119, what gives. I would like to use the offset bushings but all cam gears now have a slot instead of the hole they use to have, i dont think that slot can be drilled to accept the bushing. This engine is going in to a 69 Road Runner, auto/ stock converter, 3:23 gears, should i leave it at 111?

[creative1]

well, i dont know too much about cams, except what i have read here and on other boards, but i will tell you the little that i know. keep in mind that this is all 3rd hand info, but it could be fairly accurate.

first, the "slot" is probably a keyway. many cams use keys instead of bushings or dowel pins. like the bushings or dowel pins, the keys can be bought with offsets.

secondly, i have heard that many aftermarket cams are ground 4* retarded, meaning that a 115* center line will really be 119*. this would make sense, your cam seems to be just that way. why they do this, i dont have a clue... unless there are just so many people wanting the 4* of retard that it has become standard operating procedure.

as i said initially, i dont know if i am right in either of these areas/guesses, but they DO make sense, to me anyway. i could be way wrong though... so i would wait for someone else to either verify or condemn my statements. i would be satisfied if i only got one of them right.

[don340-4]

creative1 I didnt know about the cams bieng ground 4 degrees retarded, the timing chain set i am using has three slots in the crank gear to use 4 degrees retarded, 4 degrees advance & straight up which is the 0 setting. the big block cams use a round index pin & the small blocks use a keyway on the cam. Im just trying to find out if 111 is the recomended installed centerline for the cam i am using.

[don340-4]

can anyone explain why the cam retards 8 degrees when using the 4 degree retard slot on the crank gear portion of the Mopar timing gear & chain set, this is making me crazy.

[jelsr]

As I understand it the multiple keyway setups are not real accurate so this could be part of the problem. Also keep in mind that 2 deg at the crank is only 1 deg at the cam. (crank turns twice to the cams once)

[don340-4]

jelsr thanks for the reply, what has me confused is when i move the cam gears to the 4 degree retard settings & reset the mopar degree wheel to 0 at tdc of #1 cyl, i expect to go from 111 to 115, when i go thru the cam centerline procedure at the #1 intake lifter it comes in at 119. what am i missing here?

[perfmachst]

hello, the crank gear is not cut right.I've found more than one this way. the cam is usually ground with a 4 degree advance in them. install it at the 111 CL. it will run a lot better there versus 119 CL. most performance cams are ground with advance in them. 111 degree should be the proper setup. I haven't seen or heard of any cam ground with retard in it. the motor would be a complete dog, no power or torque. just food for thought.

[B.Tallent]

why do you want to retard the cam?most of the time the cam is advanced, at the least it is left "straight up" with a small cam such as yours.Chrysler recommends a four degree "advance" from advertised centerline.

[TK]

Originally Posted by perfmachst

hello, the crank gear is not cut right.I've found more than one this way. the cam is usually ground with a 4 degree advance in them. install it at the 111 CL. it will run a lot better there versus 119 CL. most performance cams are ground with advance in them. 111 degree should be the proper setup. I haven't seen or heard of any cam ground with retard in it. the motor would be a complete dog, no power or torque. just food for thought.

ford M blocks and smog 460's are ground with retard! (retarded fords)

[71SATELITE]

I know for a fact that comp cams grinds theirs with a 4 degree advance.

[don340-4]

thank you all for helping me out on this, i didn't want to install the cam retarded i was just trying to get a little closer to the rec. install centerline so i"ll just go with 111. thanks again