opinion comp magnum roller.

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1Fast340

1Fast340

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looking at a comp magnum solid roller for a 416stroker 11:1compression,ported RPM heads, edelbrock tunnelram,17/8" TTI headers,3800rpm converter, 3185lbs duster looking for a cam with alitle atitude but still nice and somewhat gentle on valvesprings. does this seem like a reasonable cam?

20-702-9

Basic Operating RPM Range:4,000-7,200
Duration at 050 inch Lift:262 int./262 exh.
Advertised Duration:308 int./308 exh.
Lift 0.575 int./0.575 exh.
Lobe Separation (degrees):110
Intake Valve Lash:0.020 in.
Exhaust Valve Lash:0.020 in.


i know how the 242/248 comp XR solidroller behaves in a stockstroke 340 and that one seemed quite mild in the stock stroke 340:D would a magnum roller be atleast alitle less mild mannered in a 416 compared to my previous experience?

Thanks in advance
 
Lift seems "reasonable",and you know your stuff(by reading past posts).... I ran a [email protected] hyd. flat tappet came,in a 10:1 408.Agrressive,YES. Unstreetable,depends on you... Knowing gears out back, would help immensely. I would consider. 575 lift on a solid roller,mellow. I have seen bigger,live on the street(limited use,and maintenance!!!).
 
Abodybomber said:
Lift seems "reasonable",and you know your stuff(by reading past posts).... I ran a [email protected] hyd. flat tappet came,in a 10:1 408.Agrressive,YES. Unstreetable,depends on you... Knowing gears out back, would help immensely. I would consider. 575 lift on a solid roller,mellow. I have seen bigger,live on the street(limited use,and maintenance!!!).
Click to expand...

Thanks! its a delicate act of walking the fineline of keeping valvesprings alive when you have a car that runs alot of miles in the summers:) mainfocus is finding a cam with good power and atitude that dont eat valvesprings basicly.

Choice of reargears is still out there,im burning up the searchengines on local junkyards trying to find a Dana60 that i can put under the car after getting some help cutting it down and get new ends and axles put in and they seem to be around with 4.10gears and suregrips,just takes time finding one within reasonable distance and for a reasonable price.looking for 4.10:1 gears but will probably be happy with anything close to that if the price is right and within reasonable distance..
 
Some of the Isky Red line ,or Crower's H.I.P.P.O's,would work.( continuously oiled...).
 
Well, the way I see it that you ethier get the right valve spring for best control and upper rpm power or you run a softer spring for less of that and extended life. Also since a stroker eats up a little duration, it also acts milder due to the increased cubic inches of the engine size.

Valve springs are cheap and easy to change out with the right tools. I could even be done with the head on the engine. Which is a little harder to do in the right spots in the engine bay. You just need the proper leverage.
 
I almost tried that cam, but I ended up going with the 20-740-9 instead (XR286R):

Basic Operating RPM Range:2,800-6,800
Intake Duration at 050 inch Lift:248
Exhaust Duration at 050 inch Lift:254
Duration at 050 inch Lift:248 int./254 exh.
Advertised Intake Duration:286
Advertised Exhaust Duration:292
Advertised Duration:286 int./292 exh.
Intake Valve Lift with Factory Rocker Arm Ratio:0.576 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio:0.582 in.

My motor is close to the same as what you have listed, except I have a little less compression (10.89:1), single 4 barrel carb (750dp), 1 3/4 headers, and my car weighs a little more. I use comp 939-16 springs with this cam set up at 1.85" (~185lbs seat and ~465lbs open). I have run the car hard for 5 years now with this combo, still going strong....just your "average" mid 10 second street car :D. She went 6.76 @ 100mph in the 1/8 this fall, and I guarantee she will go faster this spring with some new tires (the current tires are 3 years old...over 200 passes and at the bottom of the wear markers).
 
rumblefish360 said:
Well, the way I see it that you ethier get the right valve spring for best control and upper rpm power or you run a softer spring for less of that and extended life. Also since a stroker eats up a little duration, it also acts milder due to the increased cubic inches of the engine size.

Valve springs are cheap and easy to change out with the right tools. I could even be done with the head on the engine. Which is a little harder to do in the right spots in the engine bay. You just need the proper leverage.
Click to expand...

no problem with the springs,the cam im looking at uses the same part# springs as my current cam with bassicly the same lift,just a bunch more duration, just want to get alitle more attitude and preferably without killing springs to often LOL
 
flyfish said:
I almost tried that cam, but I ended up going with the 20-740-9 instead (XR286R):

Basic Operating RPM Range:2,800-6,800
Intake Duration at 050 inch Lift:248
Exhaust Duration at 050 inch Lift:254
Duration at 050 inch Lift:248 int./254 exh.
Advertised Intake Duration:286
Advertised Exhaust Duration:292
Advertised Duration:286 int./292 exh.
Intake Valve Lift with Factory Rocker Arm Ratio:0.576 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio:0.582 in.

My motor is close to the same as what you have listed, except I have a little less compression (10.89:1), single 4 barrel carb (750dp), 1 3/4 headers, and my car weighs a little more. I use comp 939-16 springs with this cam set up at 1.85" (~185lbs seat and ~465lbs open). I have run the car hard for 5 years now with this combo, still going strong....just your "average" mid 10 second street car :D. She went 6.76 @ 100mph in the 1/8 this fall, and I guarantee she will go faster this spring with some new tires (the current tires are 3 years old...over 200 passes and at the bottom of the wear markers).
Click to expand...

that combo sure runs :blob:
i already have your cams littlebrother in my stockstroke 340 the XR280R and find it kind of mildrunning,just thought the Magnum roller would give alitle more attitude considering the gain in cubes im looking at:burnout:
 
Use a good valvespring and I don't think you will have to worry about eating springs up with street miles.

I am putting a crower solid roller with .680 lift at the valve into my street/strip motor that see's lots of miles...Good valvesprings and lifters will be key, as well as rockers and pushrods
 
Same comp cam in a 10.5 to 1 rb 500 with indy ez,s.To give you an idea what kinda chop that cam has.[ame="http://www.youtube.com/watch?v=joBJHaHfXhs"]Damn shes dirty - YouTube[/ame]
 
mshred said:
Use a good valvespring and I don't think you will have to worry about eating springs up with street miles.

I am putting a crower solid roller with .680 lift at the valve into my street/strip motor that see's lots of miles...Good valvesprings and lifters will be key, as well as rockers and pushrods
Click to expand...

LOL, in other words, "Use quality parts and worry not!"
 
mshred said:
Use a good valvespring and I don't think you will have to worry about eating springs up with street miles.

I am putting a crower solid roller with .680 lift at the valve into my street/strip motor that see's lots of miles...Good valvesprings and lifters will be key, as well as rockers and pushrods
Click to expand...

daredevil said:
Same comp cam in a 10.5 to 1 rb 500 with indy ez,s.To give you an idea what kinda chop that cam has.Damn shes dirty - YouTube
Click to expand...

rumblefish360 said:
LOL, in other words, "Use quality parts and worry not!"
Click to expand...

mshred said:
Sure...never hurts to get specific though
Click to expand...

Thanks for the advice and that video sounds good!

Maybe i should look for alitle more lift while im at it then,have looked at a cranecam aswell,but not sure it would be worth all the extra work setting up the heads for more lift thought.. the crane cam i have looked at is a 260/266@ .050 and .630" lift but would require cutting down the guides and cut the springpockets aswell(not sure if i would run into oilingisues also at that point around the lifters even with the complifters would probably need to figure out a good way of checking that). the man who ported my heads years ago said no real point in going past about .600" lift with these heads,the headsbasic design is basicly junk in his opinion trying to get them to flow smooth at higher lifts,and i trust him(works on prostock cars) and .630" lift in the catalog would be just under .600 at the valve with the crappy pushrodangles,alitle flex and the lash.

sorry for the long post.
to much going on in my head with this camchoice.
 
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