need to learn about camshafts....

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pjc360

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I have a 300 hp crate 360 magnum engine, i'm trying to determin what the best camshaft would be for low to mid range torque, for this engine is in my half ton four wheel drive truck. I need to be schooled on camshafts and camshafts sizes and what sizes provide torque and what cams provide horse power.
I dont know anything aabout cams and i wanna learn. I'm looking for a camshaft thats going to provide real good low to mid range torque.
 
go on comp cams cam quest, google cam quest

helped me pick my cam n you can goof around for a good hour messin with otherstuff
 
also need to consider vehicle weight, driveability, torque converter stall, and rear end gears

under .270 lift and 470 duration or vise versa cant exactly remember which is what haha is a good rule for street car 360


270 duration and 470 lift. thats more like it
 
Ignore Camquest.it blows.On a Magnum,with stock heads,you are limited to. 510 lift.The lifters are reusable.Peak lift on stock heads are .480/.490 lift.If not porting heads,run with that lift.Youwill need new valvespings/retainers,call Hughes on that.Spend the extra C note on a new cam core,otherwise you have to deal with valvetrain silliness.Crower was the cheapest,stay away from reginds if you can.
 
Just askin....what's wrong with the one that's in it?
 
Now,you are pretty close,Duster Wonder.Actually,Stroker reminded me,try a set of V 10 rockers ..25 to.030 more lift.A nice new set of springs would help.If you got coin a new REAL DOUBLE ROLLER chain will make you smile.It is the small details,they call it blueprinting .
 
Abodybomber said:
Now,you are pretty close,Duster Wonder.Actually,Stroker reminded me,try a set of V 10 rockers ..25 to.030 more lift.A nice new set of springs would help.If you got coin a new REAL DOUBLE ROLLER chain will make you smile.It is the small details,they call it blueprinting .
Click to expand...


umm... no... blue printing is getting all the machine work so it (block, heads, etc) match what the design specs showed, as what was produced can be... well... off
 
Here are some specs from mopar books I have.

Stock 5.9 Magnum cam 249/269 .410/.417 117

Mopar 360/300 hp cam 240/264 .385/.401
 
If you really want to learn about cams more that just make a selection you could pick up a copy of this book. It's a bit old the the basics are the same ..... Basic Cams, Valves & Exhaust
[ame="http://www.amazon.com/Cams-Valves-Exhaust-Systems-Series/dp/0822760002/ref=sr_1_6?s=books&ie=UTF8&qid=1338554748&sr=1-6"]Amazon.com: Cams, Valves, Exhaust Systems (Hot Rod Shop Series): Books[/ame]
 
Simply make sure whatever source you use for information is not biased. In other words, ain't got nuthin to sell. The Comp camquest thing to me is tainted, simply because all they are gonna show you are their cams...cause they wanna sell you one. Same with Mopar Performance....although their performance manuals are a WEALTH of information....I highly recommend them. Just remember as you read them that they too are trying to sell you Mopar Performance parts. As long as you keep that in mind, you should be ok. Simply don't get caught up in all the BS propaganda hype. One of the magazine sites such as Mopar Muscle or the like would be a good place to start.....bet even they have agendas to sell parts for their sponsors, so you still need to be careful.
 
The first part of the Hot Rod article I posted a link to, basically states that the 360/300 crate motor is a great truck engine as is.
 
I drive a 5.9l jeep grand cherokee limited its got all the bottom end you need but it's done by 5000 rpm. The factory cam has very little lift if you go with an aftermarket cam with similar duration but more lift you'll keep your torque, open up the powerband make more HP. It will help passing but not towing, it would be hard to improve on the factory cam for bottom end towing power.
 
Actually,valvetrain work is blueprinting.(Eliminating all the variables in discrepancies from stock,otherwise shlock valve jobs and .005 valve to valve guide clearances don't kill h.p.,and reliability.)
 
This is the cam I run in my Magnum.

http://www.summitracing.com/parts/CCA-20-746-9/

It idles nicely with a little lope, has strong low-mid range torque, but also pulls fairly strong to ~5500 rpm. It's not quite right for my application (I need more cam) but it would be perfect for a truck (what I originally bought it for, spec'd by Comp Cams).

No modifications needed other than a valve spring upgrade.
 
UOP said:
This is the cam I run in my Magnum.

http://www.summitracing.com/parts/CCA-20-746-9/

It idles nicely with a little lope, has strong low-mid range torque, but also pulls fairly strong to ~5500 rpm. It's not quite right for my application (I need more cam) but it would be perfect for a truck (what I originally bought it for, spec'd by Comp Cams).

No modifications needed other than a valve spring upgrade.
Click to expand...

Looks really good for his application....
 
Hey,U.O.P,got a question, if you have the time.What does that combo foash on the converter?(if you know)
 
Abodybomber said:
Hey,U.O.P,got a question, if you have the time.What does that combo foash on the converter?(if you know)
Click to expand...

From a 5 mph roll it'll flash to ~3100. It's supposed to be stalled to 3400 but I think it's a bit loose.
 
run what's in it and add 1.72 roller rockers - to calculate gross cam lift you multiply the cam lobe lift by 1.5, 1.6, 1.72, ect... Magnums come with 1.6's IIRC.. just be sure to rotate the motor over by hand 4 revolutions slowly to make sure the valves clear the pistons..
 
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