I'm currently running the Summit 6401 cam with (9.35.1)

282/292 adv duration
.465/.488 lift
114 LSA
(calls for min. 9.5:1 compression but seems to work very nice)



Comp recommended the 268H (21-223-4)

268/280 adv duration
.477/.480 lift
110 LSA


Why/is the Comp cam better for my setup for street driving. What are the differences in characteristics?

The reason why I'm asking is, I have to change the cam & lifters due to a bad lifter issue (long story ). Putting in a different cam may open up a can of worms with lifter preload and I don't want to go through ordering a new set of pushrods again. If I'm not going to notice a difference, it won't be worth the hassle. I might as well put another 6401 cam in...

advertised durations mean next to nothing?? why the industry standard uses .050?

I don't think you would see any difference in performance the comp cam will give an ever so slightly rougher idle and a bit more and a tiny bit
more hp.

Why would lifter pre load be enough difference to worry about they are most likely ground on the same base circle unless summits is a smaller chevy size.

the comp cams cam advertised rating is at .006 lobe lift. the summit cam is the old crane HMV-278-2 that the advertised rating is at .0042 lobe lift. the problem with advertised numbers for the average person is that cam grinders use different lobe lifts for ratings. it really isn't an issue once you understand who is doing what. with .050 number everybody is on the same playing field. solid lifter and roller profiles are really a little more complicated for advertised numbers but once you understand the system a lot of the fog goes away.
the comp cams 268, with 110lsa and 4 degrees of advance ground into it,will give more low end torque but horsepower will peak sooner. it's more aggressive lobes are more failure prone. the summit cam with its 114lsa will have a more gentle torque curve, probably no big difference in horsepower compared to the 268, and will probably last longer. the real issue is the tappets that are causing a problem. you probably have gotten a set of Stanadynes with the summit camshaft. those tappets are crap. depending on how much wear you have on the lobes of the summit cam i'd think about a new quality tappet and do a break-in again. spring pressures and rocker ratio may come into to play also.

I would use the comp if you have it. there is a standard base circle for most mopar cams I'm sure you are fine.



No adjustable rockers?


The summit cam is 224/234 @ .050
the comp cam is 224/230 @ .050

Thanks for all the replies. I would like to use the Comp cam based on the response, but what scares me is the comment "more aggressive lobes are more failure prone". Hey, I'm all for more power but I have enough problems with the MILDER cam. I don't want to have to go through this again soon...

Valve train noise doesn't bother me as long as I know it's normal...

I'll have to put some more thought into it....

Valve train noise doesn't bother me as long as I know it's normal...

I'll have to put some more thought into it....

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Do put more thought into the valvetrain, since it's a MAJOR part of power production. Adjustable rocker arms would be a good insurance policy with hydraulics, as well as
matching (rate) valve springs. In reality, it's best to go with a complete cam kit. Performance-wise, it's just common sense!