MoparFins

Techical Discussions => Tech- - Engine => Topic started by: Steve on November 14, 2009, 04:36:51 PM

Title: Here I go again. . Cam Question
Post by: Steve on November 14, 2009, 04:36:51 PM
I can never seem to remember the cam technology. . .
 
I am trying to replace the cam in the new 5.9 with something a bit more economical and to deliver more torque.
 
This is the cam I used int he 5.2.  Comp wants 900 bucks for this now.  I didn't pay anywhere near that.  When I search Summit, it comes up with 2 cams
 
(http://www.moparfins.com/forum/attachments/5/Crane.jpg)
 
I am looking for a nice MPG cam for a 5.9 magnum.  This one has worked out very well.  I suspect I may be able to get the same MPG or maybe a bit better with the 5.9.  But it will make that car run!  Has the same Torque and HP as a 383 does.
Title: Here I go again. . Cam Question
Post by: Herman on November 15, 2009, 01:22:26 AM

Quote from: POLARACO
I can never seem to remember the cam technology. . .

Don't worry, it'll only get worse... (http://www.moparfins.com/forum/smileys/smiley2.gif)

(http://www.moparfins.com/forum/smileys/smiley3.gif)


You say 2 cams but only show one...
What was the question anyway?
Less duration, more lift = better torque.






Title: Here I go again. . Cam Question
Post by: Steve on November 15, 2009, 05:36:10 AM
It was at the bottom
 
I want to replace the original factory cam.  It's still a virgin, but wanted to get more MPG and move the torque line down like i did on the 5.2
Title: Here I go again. . Cam Question
Post by: firedome on November 15, 2009, 08:56:09 AM
I always thought factory cams were pretty much already designed for
torque and mpg at lower rpm as opposed to high lift, big overlap and
peak hp at higher rpm.

Title: Here I go again. . Cam Question
Post by: Rich on November 15, 2009, 09:48:42 AM


I looked up hydraulic Roller cams for newer magnum computer controlled engines, and they are $340:

http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=CTGY&Store_Code=CC&Category_Code=LACAMRFHRCC92-02 (http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=CTGY&Store_Code=CC&Category_Code=LACAMRFHRCC92-02)


krautmaster2009-11-15 14:50:31
Title: Here I go again. . Cam Question
Post by: Stan Paralikis on November 15, 2009, 12:40:54 PM
Quote from: POLARACO
I
 
This is the cam I used int he 5.2.  Comp wants 900 bucks for this now. 
Are you NUTZ?!?!
 
Comp has plenty of 5.9 cams ground for torque for about 150 bucks....
Title: Here I go again. . Cam Question
Post by: Steve on November 15, 2009, 03:30:39 PM
I thought so, but I realized my Trojan blocker was not allowing me to view them. 
 
I am looking to squeeze as much MPG out of this as I can.  None of those cams The Kraut found fit the ticket.  I think.  I need lifters too.  They got water in them.  Not going to risk it
 
To do what I want, more MPG, should I look for more HP or torque from a cam?  I would think more torque.
 
In the diesel world, I have my truck up to 600 HP and 1100 Lb Torque. Stock is 350 HP and 550 Lb.  My mileage has been climbing up and up.  Here, the more HP and torque I developed, the better it got.  All I need to do it reach the top efficiency now.  So I changed the HP to weight ratio.  Is that the same in Gas?  I would think so.  I hear race cars getting great mileage on the street.  It looks like I am finally getting 25 Highway
Title: Here I go again. . Cam Question
Post by: Stan Paralikis on November 16, 2009, 03:27:52 AM
I still can't get out of the single digits....
Title: Here I go again. . Cam Question
Post by: firedome on November 16, 2009, 04:48:18 AM

In engineering terms, it's not possible to maximize both torque and hp
at the same time, there is always some degree of trade off...if you
look at the way that drivers in the old MobilGas Economy Runs - only us
old farts will remember those - won them, it was by minimizing rpms,
shifting up as soon as possible, using very numerically low ratios,
eliminating weight, pumping tire pressures way up to reduce rolling
friction, using brakes as little as possible...so you need to do all those things, etc etc... as far as just
the engine's part goes, you want to be using the lowest possible rpms
at any given road speed, which means you want torque over hp and use
the lowest ratio rear you can get away with, and a lockup box, if it's
an automatic. ... I'll leave it to others to say what cam
profile/timing/fuel delivery will do that best, I don't know from details on specific cams.

IMO you'll need to do all the above in order to make a significant
difference, you can't repeal the laws of Physics involved in
moving a 4000+ lb mass and it's all about Conservation of Momentum once you get moving.


firedome2009-11-16 09:50:46
Title: Here I go again. . Cam Question
Post by: Stan Paralikis on November 16, 2009, 05:15:48 AM
My company was always hammering us to death about fuel economy.  So much so, that we were constantly monitored by computer, sent to school, lectured, beaten over the head, suspended, ad nauseum.
 
Firedome hit it on the head about using the old Mobil Economy Run (yah, I remember those).
READER'S DIGEST VERSION: Know the exact RPM the peak torque is at. 
Use every means available through throttle, shifting, etc. to maintain that rpm (the sweet spot). 
Drive as if there was a raw egg between your foot and the pedal.
Title: Here I go again. . Cam Question
Post by: Steve on November 16, 2009, 06:49:09 AM
Gee Thanks stan. . .  Yer tellin a guy who get's 25 MPG from an 8000 pound pick up.
 
I know it's either HP or Torgue.  I am pretty sure I need to get the torque up and leave the HP alone.  Although, there is a ratio that follows.
 
Stan. . .The original cams in the 5.9's were pigs
Title: Here I go again. . Cam Question
Post by: Stan Paralikis on November 16, 2009, 09:41:43 AM
Quote from: POLARACO
Gee Thanks stan. . .  Yer tellin a guy who get's 25 MPG from an 8000 pound pick up.
Yah, I knew I was preaching to the choir but you did ask.....
So be careful what you ask for because any (http://www.moparfins.com/forum/smileys/smiley35.gif)hole  will chime in.  (http://www.moparfins.com/forum/smileys/smiley2.gif)
Title: Here I go again. . Cam Question
Post by: glen cyr on November 22, 2009, 05:41:19 PM
This is probably a little more cam than you are looking for,....but it would pack-a-punch! http://www.hughesengines.com/Index/products.php?browse=category&level0=U21hbGwgQmxvY2sgTWFnbnVtICgzLjkvNS4yLzUuOSk=&level1=Q2Ftc2hhZnQ=&searchmode=keyword&page=1&partid=11430 (http://www.hughesengines.com/Index/products.php?browse=category&level0=U21hbGwgQmxvY2sgTWFnbnVtICgzLjkvNS4yLzUuOSk=&level1=Q2Ftc2hhZnQ=&searchmode=keyword&page=1&partid=11430) Have you thought about installing 1.7 ratio rockers .
 
glen
Title: Here I go again. . Cam Question
Post by: Steve on November 22, 2009, 07:06:39 PM
Yeah I thought about it, but then I have to go to mechanical lifters on the maggie.
 
I'm going with just a set of high flow heads from EQ.  I am going to machine my throttle body to get better flow.  Using the stock Cam, since it's brand new and my Hughes Air Gap intake.  I can get 100 CFM if I just remove the rings on the top of the TB.  25 more if I polish the throats.  But I don't need any more than 650
 
We're figuring I'll be adding lots of torque, and a few ponies at the same time.
 
The trick is to build the torque and not the HP to get better MPG.
 
Thanks Glen (http://www.moparfins.com/forum/smileys/smiley4.gif)