Which of these 2 cams should I use and why?????

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duster360

duster360

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I am trying to decide between these 3 ( added one )cams and need some opinions as to which one to use and why?

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=631&sb=2

http://www.lunatipower.com/Product.aspx?id=1545&gid=287

http://www.summitracing.com/parts/hrs-710581-10/overview/make/dodge

Engine and car specs:
67 Dart
340 c.i.
Edelbrock airgap intake
Edelbrock 60779 heads
Hughes roller rockers
SRP pistons
9.5:1ish compression ( will be calculated before assembly )
Hooker headers
4 speed
3.91 gears ( 3.55 gears later on possibly )
 
Without intended usage ie: street or race
My personal preference would be
#1 lunati
#2 howards
#3 com
 
I run that Lunati with a 4 speed and 3.91s. Its fun on the street and has good manners.
 
you're not really comparing apples to apples in my opinion. you have three brands of cam, with three different power bands. you do see that the howards lower end is 2600 correct? and the lunati is 1800? thats a pretty big span, and enough to make your converter not perform to its potential if you went from one to the other. FYI you're going to need a torque converter with any of these, but a 1800 stall, and a 2600 stall is enough to make a difference in which one you purchase. maybe you're asking from a numbers perspective and the brand choice is irreverent to you, but I want to make sure you cover your bases. I learned the hard way how much a mismatched converter can kill a combo.
 
johnnymac2k6 said:
you're not really comparing apples to apples in my opinion. you have three brands of cam, with three different power bands. you do see that the howards lower end is 2600 correct? and the lunati is 1800? thats a pretty big span, and enough to make your converter not perform to its potential if you went from one to the other. FYI you're going to need a torque converter with any of these, but a 1800 stall, and a 2600 stall is enough to make a difference in which one you purchase. maybe you're asking from a numbers perspective and the brand choice is irreverent to you, but I want to make sure you cover your bases. I learned the hard way how much a mismatched converter can kill a combo.
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He has a 4 speed manual. For a cruiser I'd choose that Lunati or go custom.
 
dano said:
He has a 4 speed manual. For a cruiser I'd choose that Lunati or go custom.
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well than that makes me look dumb.lol thanks. but i still want him to note the power range. that 2600 low end is too much for a daily driver IMO.
 
johnnymac2k6 said:
well than that makes me look dumb.lol thanks. but i still want him to note the power range. that 2600 low end is too much for a daily driver IMO.
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Makes sense about the about the Howards cam. I did see that the Lunati and the Comp cam have 1800 and 2000 RPM low end. Lunati and Comp were my original 2 choices.
 
I think lunati and comp kind of exagerate their pwerbands. Howards is pretty accurate on there #s. my choice would be to call Howards for a custom grind, they will give youthe cam specs (lobe nember/ lift # lobe seperatin and advance) with that info you call up summit racing with that info and order your cam. here is the summit page with the custom cam # http://www.summitracing.com/parts/hrs-719991 You get a custom ground cam for less than $146 shipped! I preffer Howards then lunati comp is good though.
 
I have a Lunati 60404 in my 340 powered Duster, also with a 4 speed. That's one step up from the 60403 you have listed. Specs on the engine are

'68 340
.060" over with KB 243 hyper pistons, .018" over the deck, ~9.8:1
Forged crank, stock 340 rods, resized with ARP bolts
308 heads, 2.02/1.60 valves, 65 cc's chambers, stage II ported and flowing 264 cfm at .500" on the bench
Crane adjustable 1.5 rockers, Smith bro's pushrods
Lunati 60404 Hydraulic cam, .513/.533, duration @ .050" 234/242, advertised duration 276/284
Doug's Headers
Edelbrock Air Gap
Holley 750 Ultra DP
Milodon Road race pan, stock 340 windage tray

Haven't had it on a dyno yet, expect about 420 hp out of it or so. Pulls 9-10" of vacuum at idle, so not a whole lot. I use manual disk brakes, probably not enough vacuum for power brakes with those numbers. I'm almost to the point that I'm using the duster as my daily driver, and I'd say that this is about as much cam as I'd want to run if I'm putting 10k miles a year on the car (which is about what I do if I use it as an everyday daily). So far I have about 6k miles on it with this engine, I'm still working on the car a bit so I'm still running my Challenger around too.

The 60403 is a great cam, I bought one for my EL5 GT's 318 build. Should be a little easier to deal with than the 60404, but it will still sound great and make good power. Should work ok with power brakes if you've got them, but I would say it's probably pretty close to the limit for those.

Here's the 60404 at idle. :D

[ame]https://youtu.be/62bjHlxzsoA[/ame]
 
I have manual brakes. So no worries on that. That sounds soooooooo good 72bluNblu.
 
duster360 said:
I have manual brakes. So no worries on that. That sounds soooooooo good 72bluNblu.
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Thanks! :thumbup:

The 60404 is actually a closer match to the other two cams you listed, with an operating range listed from 2200-6400. https://www.lunatipower.com/Product.aspx?id=1546&gid=287

I think it works pretty well on the street, and I'd say that operating range is pretty close to spot on, it really starts to take off starting at 2200, at 3k things start to get pretty entertaining. For me it's about the upper limit of what I would want to drive as much as I do on the street, but if we're talking a weekend car the 60404 is no problem. You have the gears and heads for it too, you could probably even run a bit more compression with the aluminum heads. I run 91 octane at 9.8:1, but I've got iron heads. My biggest "issue" at the moment is my 2.93 rear gears. Really need more like 3.73's with that cam. I just need to upgrade to a 5 speed so I can run 3.73's and still cruise on the freeways. :D

Honestly though, if I build another high horsepower small block I'll probably go with a custom roller. Easier to make big horsepower numbers and still have good street manners down low. Like goldduster318's MRL built 340 that puts out 470 hp and still pulls more vacuum at idle than mine.
 
The main issue I have with the 60404 is the top end. Just not sure I want to wind it up that high. The closer to 6000 rpm the better for me.
 
BTW, OP, I am going through the same build preparations, and with the 63 cc chambers of the Edelbrock 60779's, and with standard SRP pistons' compression height (flush with or below the block, not above the block like the standard 340 or KB243 pistons; the SRP's comp height is .036" lower than the KB243's), you are going to have to use thicker head gaskets to keep the SCR down near 9.5:1 and your quench space will then be much larger than recommended. You may be better off running a thin head gasket with higher CR and keeping the quench gap close to optimum. The AL heads will help you; if 72bluenblu can run 9.8:1 with iron heads, you ought to be OK.

With the cam duration numbers you are looking at will keep the DCR well down.

Have you ever ridden a 2-stoke motorcycle? Going too high on duration will be like that: rev and rev and slip the clutch to get it going.....so going too long on duration on your manual trans will be that way. Of course, the 3.91 will help but going to the 3.55 may not be a good option later with too much duration.
 
I don't think you will see much difference between any of those cams. Put three pieces of paper in a hat with the three cams on them and pull one out. Run that one.
 
nm9stheham said:
BTW, OP, I am going through the same build preparations, and with the 63 cc chambers of the Edelbrock 60779's, and with standard SRP pistons' compression height (flush with or below the block, not above the block like the standard 340 or KB243 pistons; the SRP's comp height is .036" lower than the KB243's), you are going to have to use thicker head gaskets to keep the SCR down near 9.5:1 and your quench space will then be much larger than recommended. You may be better off running a thin head gasket with higher CR and keeping the quench gap close to optimum. The AL heads will help you; if 72bluenblu can run 9.8:1 with iron heads, you ought to be OK.

With the cam duration numbers you are looking at will keep the DCR well down.

Have you ever ridden a 2-stoke motorcycle? Going too high on duration will be like that: rev and rev and slip the clutch to get it going.....so going too long on duration on your manual trans will be that way. Of course, the 3.91 will help but going to the 3.55 may not be a good option later with too much duration.
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I figure with the aluminum heads as long as compression is 10:1 or under everything will be fine.
 
duster360 said:
I figure with the aluminum heads as long as compression is 10:1 or under everything will be fine.
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You can usually get away with a full point more compression with aluminum heads compared to iron. Meaning, you should be able to manage almost 11:1 on 91 octane depending on your cam, quench, altitude etc.
 
72bluNblu said:
You can usually get away with a full point more compression with aluminum heads compared to iron. Meaning, you should be able to manage almost 11:1 on 91 octane depending on your cam, quench, altitude etc.
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That is good to hear. On a side note, I had the '69 340 block square decked this go around and he cut .006" off the deck surface on one side and .022" off the other. Must have been one of those late Friday evening, do one side and finish the other Monday morning deals when the engine was done at the factory. lol
 
I have a 340 with the air gap manifold edelbrock heads hooker headers that exact lunati cam amd a 670 street avenger. I have about a 10.5 compression with 3.55 rear end. I got compliments all the time on the lope and it makes good power down low with a stall converter and pulls hard to 6k easily...now that I fixed my timing issue.
 
jcarr210 said:
I have a 340 with the air gap manifold edelbrock heads hooker headers that exact lunati cam amd a 670 street avenger. I have about a 10.5 compression with 3.55 rear end. I got compliments all the time on the lope and it makes good power down low with a stall converter and pulls hard to 6k easily...now that I fixed my timing issue.
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That is good info to know. Thanks.
 
Hi, Just a note here on the comp cam choice. My understanding is that this particular grind/series takes advantage of the larger lifter bore mopar uses in the small block allowing for a faster lobe profile. Its the one I plan on using in my 340 if I ever find a money tree.

Don't remember which mag had the build. Mopar Muscle maybe? But that cam was used in one of their 318 builds and it pumped out 415 hp on a milled J-headed build with 2.02 OEM mopar valves, stock rockers, very minor porting, zero-decked 318 block with KB pistons @ .040 over, eddy air gap and an untuned TQ (at first)1 point too rich with a 1" adapter for 408 hp and later a 750 demon and lighter oil for the 415hp. Peak HP was around 6300 and it help decent up to 6500. Nasty. :burnout:

The title was "Cheap as dirt: 415 HP 318" If that's not the exact title, it's darn close. Nearly impossible to find on the web. Article was pulled late last year when several mags were combined on the web. Have a copy I pieced together from quotes in different forums. I could send it in a PM or whatever if you'd like.

Paul.
 
1968notch said:
Hi, Just a note here on the comp cam choice. My understanding is that this particular grind/series takes advantage of the larger lifter bore mopar uses in the small block allowing for a faster lobe profile. Its the one I plan on using in my 340 if I ever find a money tree.

Don't remember which mag had the build. Mopar Muscle maybe? But that cam was used in one of their 318 builds and it pumped out 415 hp on a milled J-headed build with 2.02 OEM mopar valves, stock rockers, very minor porting, zero-decked 318 block with KB pistons @ .040 over, eddy air gap and an untuned TQ (at first)1 point too rich with a 1" adapter for 408 hp and later a 750 demon and lighter oil for the 415hp. Peak HP was around 6300 and it help decent up to 6500. Nasty. :burnout:

The title was "Cheap as dirt: 415 HP 318" If that's not the exact title, it's darn close. Nearly impossible to find on the web. Article was pulled late last year when several mags were combined on the web. Have a copy I pieced together from quotes in different forums. I could send it in a PM or whatever if you'd like.

Paul.
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All Lunati cams are set up to take advantage of the mopar lifter size.

Comp Cams were the ones that used to have cams that were based off chevy lifter sizes. Don't think they still do that, but that's why that info was out there.
 
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