440 stroker engine to roller cam or Mr Six pack cam??

Hello guys,
I need some input here as I have been driving my 71 charger rt for a couple years now probably 1500-2000 miles total and from time to time when it is warmed up I can here a light ticking from valvetrain and the car does seem to be down on power from when I first got it out.

Here are the specs:
-440 stroker with 440 source 500 inch stroker kit
-9.8 to 1 comp
-stealth heads with no porting but upgraded springs and retainers/locks
-Comp Cam Xtreme Energy Hi-Lift .564"(does NOT purr like a kitten like they state it is rough as hell and only 10-12 lbs vaccum)
-source roller rockers with spacers under stock Valve covers
-6 pack intake/carbs rejetted with quick fuel plates & lighter springs
-stock hp exhaust manifolds (had headers but went back to manifolds for car shows as it goes in stock class)
-recurved electronic dist 20 initial and 38 total chrome MP box
-3200 stall convertor in beefed up 727
-3.91 rear gears

Here are my concerns:
The car idles like crap very rough and all the tuning I have tried does not help but I can live with that. I know the cam is to blame and it worked good when I had headers on it but with the manifolds the car is all done at 5200-5400 rpm so the cam is TOO big for this combo now.

So over the winter I want to swap in a new cam and I was going to go with the Mr Six pack cam but my engine guy brought up a good point as the car has dual springs on it and he would want to remove those to break the cam in so it does not take an early crap due to high spring preasure. That got me thinking does it make more sense to put that $300 roughly of labor to pull the springs and put them back on when broken in towards a roller setup instead? I did some looking and I am really liking the Lunati roller cam kit: https://www.lunatipower.com/Product.aspx?id=4642&gid=365

Has anyone had any experience with this or another roller cam kit? I think this one looks good from my combo as I want some major torque down low but also a little top end until those stock manifolds cut me off around 5500. is it a pretty straight forward conversion? Will I need new pushrods(have crane ones in there now), a new dist drive? Just wondered what I will all be looking at and if it is worth it to do the roller or just do the Mr Six pack cam?

INPUT PLEASE!!

If your cam is the XE295HL then I'm not surprised. It isn't a super big cam but 251/257 at 050 on a 110 center will give you a rough idle even in a 500 inch motor.

You should read the article I wrote a few years ago on cam testing in my '65 Coronet. Sounds like the same situation. The Mopar .528 solid would work pretty well for you but so would a ton of other cams. You just need to stay in the 235 to 245 range on the duration and keep the lobes spread out a bit to reduce overlap.

http://www.moparts.org/Tech/Archive/bb/Lobe.html

I would put the cam in at 102 not 106 (comps are Typically +4) Ironically I'll bet you a 257/257 cam in at 102 would both idle better AND give you more power.

IMO, A late closing intake event (relative to the lobe size of course) combined with too small an @.050 lobe can turn even a decent headed 500" stroker into an Oldsmobile (all torque with not enough up top) type powerband. My stuffs on youtube, type in wizerulz.

I usually run at least 22-24 degrees of initial and 36 total on my street stroker stuff. And the Carb tuning makes a huge difference on strokers too. I like a Great (choppy but snappy) Idle and seriously quick throttle response on my stuff.

I've run that 251/257 Comp before on high 11 440" (stock stroke) motors with fairly tight converters and mid 3 gears, might want to dig a little further into the tune, chassis dyno with a good tuner would be money well-spent before tearing into it, after all you might only be treating the (wrong) symptom. 3200 stall (I'm assuming a 10") might drag down the low response as well, a good quality tight 3800 stall 9 1/2" would work better in a heavy B and drive out as well or better at part throttle.

also I suggest you compare tuning notes with Paul PHJ426, he has my old 508" RB with a six pack in a similar 71 Road Runner with a lot tighter gearing than your 3.91's, he LOVES it.

Just call some one not named comp and order a cam for your combo.

bingo! good advice!

Call Bullet cams.........

I'm putting a Mr Six pack cam in my 496 6 pack. I know it's way too small for this motor. But I don't plan on doing any racing with it at all. And I wanted a cam with excellent vacuum for the six pack to work good. I've heard nothing but good things about them. Should have mine done by mid September. I'll let you know how I like it.

The ONLY reason to run a Mr Six Pack cam is if you're building a car to run in Pure Stock AND plan on running at the front and will be tech'd...otherwise, there are plenty of cams out there that will idle smooth and make more power...I recommend Porter for a custom grind...802-951-1955

more good advice.

I agree Dwayne Porter will certainly get you a great custom grind.

That said the 251/257 Comp you have shouldn't and won't be a bad choice for a Hydraulic flat tappet for the powerband you're looking for. Or I'll say you can do a heck of lot worse. As I said I've used that very grind and have seen even stock stroke 440" 4000 pound cars/W driver (in this case a 70 Charger) run consistant high 11's @ 114 with a tight converter and 3.23 (!!!) gears with it. it's easy to slam the Comp cams tech guys, but like the saying goes..."even a blind squirrel finds a nut every now than then"

The Lunati cam you have picked would make you very very happy. I have used the small block counterpart of that cam in a 360 and it has tons of vacuum, almost stock idle and pulls everywhere up until about 5800 rpm. If you are leaning towards a roller then go this way. If not, there are plenty of hydraulic flat tappets that can do what you are asking as well. J.Rob

Why do you think you need "excellent vacuum" for the six pack?

[/quote]
Why do you think you need "excellent vacuum" for the six pack?[/quote]

Don't underestimate vacuum on a street engine. Never thought much about it until I did not have any and it is a BI$$$ tuning a 6 pack without a good solid vacuum level, plus when you run pb, a/c, and other access. it can get real hard without it!!

My Indy EZ headed 493" six pack motor idles at 6" of vacuum, has power brakes that work flawlessly and a Promax modified mechanical outboard six pack set-up that was tuned on the road with a wide band. It makes all its power below 6000 rpm, so it has a relatively smallish cam.

The wide band tuning made all the difference with finding the jetting it wanted.

bingo! another winner!

A comment on the "ticking". A small exhaust leak can sound a lot like a valvetrain/lifter problem. Are you sure you have a valvetrain tick?

Also, the roller helps in some areas like less sensitivity to break-in and lube oil and spring pressure... but has its drawbacks also with fast wear on the bronze OP gear usually needed and lifter life sometimes... not to mention cost.

Since you are not really pushing lift and don't need to push spring pressure something like the "528" Mopar flat tappet would work well. With that a single spring should be fine... similar to what comes stock with Ed RPM or Stealth heads.

Another vote for Dwayne Porter. I run one of his custom solid flat tappet cams he speced for me and I love it. It works just as I wanted. Ron