Announcement

Collapse
No announcement yet.

Cams and torque

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Cams and torque

    Hello guys in my quest to learn more about cams I would like to pick everyones brain.
    As I plan my build for my vic I am looking at cams to get monster torque off the line and across the RPMS here is my ??
    What makes a cam a torque cam? is it duration? lift? the power band the cam will work in? I know all these play a factor but I see so many cams that have similar numbers but the are listed at differnt power bands some say like .448 .472 power from 800-4500, then I will see a similar cam that says its good till 5500 same with intakes.
    I guess what I am saying is, is there a duration and lift that makes more trque down low and is there a cutoff like once I get to .500ish do i consider that a cutoof for torque cams?

    #2
    The lobe sepration angle and duration have more to do with the power band of a given cam than the actual lift number does, though the lobe profile itself (basically how fast it reaches full lift) also plays in. I'm absolutely no cam guru, its still somewhere in the realm of dark arts as far as I'm concerned, but I think a Comp Cams XE258 or maybe an XE264 might give you what you're after if you want off the line power but aren't looking for silly high RPM.

    http://www.compcams.com/catalog/COMP...og_2010_82.pdf
    86 Lincoln Town Car (Galactica).
    5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

    91 Lincoln Mark VII LSC grandpa spec white and cranberry

    1984 Lincoln Continental TurboDiesel - rolls coal

    Originally posted by phayzer5
    I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

    Comment


      #3
      With the melling MTF-5, .450 int lift, .474 exh lift 280 290 duration.. I have peak tq (320 rwtq) at 1800 rpm with only about a 10 ftpd difference throughout the rpm range. Of course my motor is done at 5k.
      1984 CV tudor 351W, 4bbl, 5-speed best time in the 1/8 8.39 at 80 with 1.80 60ft time.
      2006 P71, 1988 Bronco II, 1986 Baby LTD(5.0 & T5 swap in progress), 1976 16' Hobie Cat, 12' AquaFinn
      http://www.cardomain.com/ride/2651997 UPDATED 20100826
      sigpic

      Comment


        #4
        Call the tech assistance for the cam manufacturers and tell them what you are looking for and the application depending on your set up and they can recommend a cam ideal for your needs.

        2011 Grand Marquis LS Ultimate Edition
        Dual Exhaust w/ AP XLerator mufflers and 3 1/2" tips, Eibach 1" rear sway bar, Pioneer Head unit and speakers, 17X8 Drag DR-72 wheels

        RIP 1984 2Dr Crown Vic "The Millennium Falcon"
        Carbed 5.0 HO w/nitrous , Performer RPM intake, GT40P heads, E303 cam, FRP Shorties, FRP 9mm plug wires, Off-Road H-pipe, Magnaflow round mufflers, 2000 rpm stall
        NA-15.78@91.21, 80hp shot-14.48@96.21

        Comment


          #5
          XE258 FTW!!!!! part no 35-510-8
          89 townie, mild exhuast up grades, soon to have loud ass stereo....

          Comment


            #6
            Ughhh


            '90 LX 5.0 mustang
            Big plans

            Comment


              #7
              Sooo I got a question?? if I have a lower comp. ratio say around 8.1, is there timing or duration I can look for that can help fill the cylinder better to make better power?

              Comment


                #8
                Smaller cams are better for generating higher cylinder pressure, as they don't bleed off as much air. However, it only works so well, so if you're stuck with low compression, I'd try to snag a set of rebuilt 1965-early 1966 289 heads, as you'll raise static compression up a full point with the 54cc heads.

                What exactly are you trying to do here?

                Comment


                  #9
                  Originally posted by The Auntie Christ View Post
                  Smaller cams are better for generating higher cylinder pressure, as they don't bleed off as much air. However, it only works so well, so if you're stuck with low compression, I'd try to snag a set of rebuilt 1965-early 1966 289 heads, as you'll raise static compression up a full point with the 54cc heads.

                  What exactly are you trying to do here?
                  Well basically I am going to be building a 351m for my vic, for the time being before i can get nice heads and turn it into a 400, I was trying to make this thing run good.

                  Comment


                    #10
                    mill the heads down to make the combustion chambers not resemble half a softball in volume.

                    I'm guessing you're already aware of the specifics of using a 351M, namely the different bellhouse and engine mount points and have planned something to work around that?
                    86 Lincoln Town Car (Galactica).
                    5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                    91 Lincoln Mark VII LSC grandpa spec white and cranberry

                    1984 Lincoln Continental TurboDiesel - rolls coal

                    Originally posted by phayzer5
                    I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                    Comment


                      #11
                      better off finding a 2v cleveland and building it up

                      1986 lincoln towncar signature series. 5.0 HO with thumper performance ported e7 heads, 1.7 roller rockers, warm air intake, 65mm throttle body, 1/2" intake spacer, ported intakes, 3.73 rear with trac lock, 98-02 front brake conversion, 92-97 rear disc conversion, 1" rear swaybar, 1 3/16" front swaybar, 16" wheels and tires, loud ass stereo system, badass cb, best time to date 15.94 at 87 mph. lots of mods in the works 221.8 rwhp 278 rwt
                      2006 Lincoln Town Car Signature. Stock for now
                      1989 Ford F-250 4x4 much much more to come, sefi converted so far.
                      1986 Toyota pickup with LSC wheels and 225/60/16 tires.
                      2008 Hyundai Elantra future Revcon toad
                      1987 TriBurner and 1986 Alaska stokers keeping me warm. (and some pesky oil heat)

                      please be patient, rebuilding an empire!

                      Comment


                        #12
                        wtf an M? too big and heavy, yes the 400 makes some torque, but that engine is as big as a 460, same bell housing as the 460 also, the M series has oiling problems (cleavland too) that is why not many people build them, yes they make an oil pan to fit but that is about it. if you just want easy torque do a 408W same bore and stroke as 400 (exept for .030 over bore uless you can find a good standard bore 351w block) the W is a drop in, you can even use your iron manifolds if you have to. i give you props for being different, but there is just easier ways to make power and torque.

                        Comment


                          #13
                          by the way if you are going to go through with this i do have a 400 (i was going to pirate the crank for a W but stroker cranks are pretty cheep now) if you have to rebuild anyway dont bother with a 351m.

                          Comment


                            #14
                            this site focuses alot on bottom of the barrel budget-
                            you can build a 500hp 400m alot cheaper than a 500hp 408windsor
                            the windsor is smaller and easier to package though

                            the 351c does probably make more sense though- 9.2 deck vs. 10.3 deck
                            windsor will need a $2000 set of heads to compete here
                            Last edited by jayh; 07-29-2010, 10:48 AM.

                            Comment


                              #15
                              Originally posted by gadget73 View Post
                              The lobe sepration angle and duration have more to do with the power band of a given cam than the actual lift number does, though the lobe profile itself (basically how fast it reaches full lift) also plays in. I'm absolutely no cam guru, its still somewhere in the realm of dark arts as far as I'm concerned, but I think a Comp Cams XE258 or maybe an XE264 might give you what you're after if you want off the line power but aren't looking for silly high RPM.

                              http://www.compcams.com/catalog/COMP...og_2010_82.pdf

                              Not necessarily contradicting you, but according to guys who know lots more than I do, LSA, etc. are byproducts of event-driven cam design and not a design feature. http://sbftech.com/index.php/topic,3061.0.html


                              Interesting quote:
                              110 + 116 = 226/2 = 113 EVERYTIME. But if I come at it and say I want a 113 LSA, how many different combinations of numbers can you have and get to 113?

                              Infinate.
                              (apologies for the spelling, but English is this guy's second language)


                              I gathered from another thread, I think by this poster, that a Comp XE258HR is not necessarily any more or less desirable, as I had been previously inclined to believe, than my Crane 2020 (same .050 duration, slightly less lift, 4 deg. larger advertised duration), and from a variety of inputs that production tolerances can be loose enough that you don't know just what you're getting anyway, even provided the cast core doesn't flex enough to throw everything off in your particular installation.

                              It just happens that the XE258HR helps produce some fairly attractive-looking curves on Desktop Dyno. I had previously been inclined to consider getting one in place of my Crane cam, based on the much fatter curve on Desktop Dyno, but my current understanding is that said inclination was rather silly.
                              2012 Mazda5 Touring | Finally working on the LTD again!

                              Comment

                              Working...
                              X