HP/TQ Graph for the new SOHC (3) Valve 4.6...

Discussion in '2005 - 2009 Specific Tech' started by Katmandu, Jan 12, 2004.

  1. I (and I bet a BUNCH more folks) would like to see a Graphical Comparison between this new SOHC (3) Valve 4.6 -Vs- the Mach I's DOHC (4) valved engine.

    Anyone have Graphs depicting these (2) beast ?? :shrug:
     
  2. well ask ford for a new stang engine to test
     
  3. here is what the torque curve
    will hopefully be like: _________/--------------------\_
     
  4. I doubt that we will see anything until the 2005 Mustang starts rolling off the production line. Yes the hardware is 99% set in stone at this point, but I guarantee you the software people will be working non-stop on the PCM code until a week before the production line starts up.
     
  5. I hate to tell you this but the first preproduction versions of the convertible have already rolled off of the factory floor. They will change things during production but I don't see this motor pulling the machs numbers or curves with the vvt having to adjust for 87 octane and a missing valve per cylinder. depends on the heads and cam grind. so we will see
     
  6. According to Ford the new 3valve heads flow the same amount of air as the current 4valve heads. Add in variable cam timing. And it should be fairly quick. Now as far as the 87 octane fuel. I would think one of the best mods for the motor would be a timing adjuster so you can bump the timing up to run on 93-94 octane.
     
  7. I wouldn't poo poo the 3V heads yet - Mercedes loves them and....

    Merc engines have pretty good specific output, not to mention Merc can put as many valves as they want in their heads since they're in the high end market. In fact, Audi's been using five valve heads on some of their engines! And, the Variable Valve Timing can do a lot of good. Forget about Honda's spiky VTEC, many other manufacturers, including the Germans, have had continuously variable valve timing rigs for years. It's way smoother than VTEC; you just feel a nice swell of power as the cam timing changes thru the rev range. I really think this is going to be a great engine. I will admit I'd prefer 4v heads, if for nothing else, the symmetry and classic hi po rep. that they have. But if 3v heads work for Merc, I'm sure they can't be that bad.
     
  8. I can't imagine they'd produce and engine with similar specs and have it end up pushing worse numbers. It'll be about the same as the Mach. It's not going to be a MAch enigine, but if you want that.....get a Mach. I'm interested to see where SVT goes with this one.
     
  9. Yeah, I'm wondering too especially with Shelby is in the mix now...I think Coletti(head of SVT) and Shelby are fighting over who will be top dog the SVT Cobra or Shelby GTXXX, anyway I only can imagine what the engine for the top dog Stang will be...s/c the 4v DOHC, s/c the 3v SOHC, N/A 5.4 DOHC, N/A 5.0 DOHC or something else whatever it is I bet it has some serious power.
     
  10. I have to agree with Basenji. The Honda VTEC and Toyota VViT tend to produce high power spikes but not a lot of useable power throughout the RPM range. The BMW and Mercedes versions seem to do a better job.

    I have a Toyota as a daily commuter and the VViT does not start until 6000 RPM and then the redline is at 7800 RPM. That is not very useful in daily driving. Of course, a larger displacement engine will produce better results.
     
  11. Well the HP ARE very close (according to Ford), 300HP for the (3) valve SOHC - Vs- 305HP for the (4)valved DOHC.

    I'm very curious as to the Torque Curve comparisons between these (2) engines! :shrug:
     
  12. Also, could the 3v SOHC possibly be underrated like the Mach 1 4v DOHC???
     
  13. I think it will be, same as the current 4.6L sohc is also underated.
     
  14. You probably won't need a timing adjuster. The 3V engine uses Ford's new engine control system. If it's like the LS engines the timing is automatically advanced as far as possible w/o getting knocking.

    So the easiest performance mod. could be to fill it up with 91.
     
  15. I don't agree...the current 4.6L SOHC is not underrated.

    As far as I know, the first Mustang that Ford underrated (we're talking SN95 here) was the 03 Cobra and then followed by the Mach 1.

    Please correct me if I'm wrong.
     
  16. :OT: VVT-i changes the cam timing controlling valve over lap. VTEC actualy changes the from one cam lobe to another bigger one (like Toyota/yamaha's VVTL-i). The only thing close the europeans have had is BMW's new Throttle less system "Valvetronic". I like Ford's Idea of acualy moving the whole cam but it seems destined for much mechanical hardship and confusion.
    http://www.toyota.com/html/help/glossary.html
    http://www.bmwgroup.com/e/nav/index...n/7_3_technologie/7_3_3_valvetronic.shtml?7_3
    If anyone would like a detailed explanation of how VTEC works PM me, maybe I'll start a thread in "The house of pain" this realy isn't the place and I can't find a good website with an explanation.
     
  17. If the Mach is underated then the SOHC GT motor is too.
    People claim 268-280 RWHP for the Mach 1 however the RWHP for a GT is 233-243 Both these horsepower ratings are manual transmissions. So really the Mach puts out around 40 horsepower more than the SOHC motor. And its rated 45hp higher. If you can remember back to the first 4V 4.6 it was rated at 305 HP and the RWHP was right at the 250 mark.
     
  18. I rarely see new Gts dyno over 230..

    -Ryan
     
  19. My mach puts down 280RWHP/306RWTQ stock with a K&N, that's around 330HP/350TQ at the crank. I also have an 02 GT and they put out about 230 RWHP with a stick and believe you and me there's a ton of difference in the two cars.

    As far as VVT goes it seems to me thats little more than computer controllered timing and a timing adjuster won't help for that. The computer pulls timing for gas mileage durning easy driving and adds max timing at WOT. 87 octane just won't allow timing advances as far as 91/93 octane IMO.

    I am impressed they got 300HP out of the SOHC motor but I'd be real surprised to see any more than high 250's when it's all said and done at 15% drive train loss that's about 255RWHP for the stick car.

    BTW there seems to be a lot of 280+ Mach's coming out since June 03, I think they had a rich tune on the early models and have now leaned it out for better HP/TQ.
     

  20. :bang: :bang: :bang: :bang: :bang: :bang: :bang: :bang: :bang: :bang:

    There has to have been at least 50 differnt threads discussing Ford's VCT in StangNet and you guys sill don't get it.

    VCT = variable cam timing (or VVT variable valve timing) adjusts the valve opening and closing relative to the crank position.

    The spark timing adjusts when the spark plug fires relative to the crank postion.

    A spark timing adjuster would not have any effect on the cam timing.
    That is, spark and cam timing are not tied together.