Realistic Hp/tq Expectations...

Discussion in '1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-' started by CT Grim, Sep 18, 2013.

  1. Ok. Gotcha. Yeah, commented prior to the edits.

  2. Here's what Pro-M's website has to say about the 75mm bullet:
    A general search indicates that a Lightning MAF quits somewhere around 450-500rwhp. Pretty close. I learned something here, but the point in the upgrade would be to reduce the restriction in flow. I agree with your assertion that it's not going to be worth the cost or effort, but I think it would definitely pick up something.
  3. A 75mm is no restriction to flow whatsoever. I'm still running the 75mm Pro-M I bought 14 years ago.

  4. Curious, anyone know whats the volume of air in a N/A 302, 331, 347 can bring in at one time. I think then when that's found, one could really taylor the incoming air velocity :shrug:
  5. calculation is VE*RPM/2*cubic inch displacement/1728 = volume in CFM (cubic feet per minute)

    Why do you believe that? When will it become a restriction to flow? Do you have any evidence that indicates that increasing the MAF size on an H/C/I 302 results in no power gain?

    Hell, what do I know. Maybe you're right. I don't bother with MAFs these days, anyway.
    #25 FastDriver, Sep 19, 2013
    Last edited: Sep 19, 2013
  6. would anyone care to plug number in that equation, im at work :flag:
  7. I'm not sure what you're trying to do.

    Ok, for ****s and giggles a 347 turning 6500 rpm at 95% volumetric efficiency, which is pretty good at that RPM, would be moving 620 CFM. This motor is going to make over 400rwhp at sea level under standard conditions.
    #27 FastDriver, Sep 19, 2013
    Last edited: Sep 19, 2013
  8. 20 years of experience. A 75mm is huge for a basic HCI engine. Have you seen one? You can fist the damn thing.

  9. I owned a 75mm MAF, as mentioned. FYI, 75mm is just under 3" in diameter. You have very small fists.
    Rick 91GT likes this.
  10. Found this on a forum is it right??

    73 mass air = 1171 cfm
    80 mass air = 1415 cfm
    83 mass air = 1598 cfm

    70mm throttle body = 726 cfm
    75mm throttle body = 845 cfm
    90mm throttle body = 1190 cfm
  11. If 5spdGT posted it, it probably was well researched.... sounds like something he's done here. Consider the fact that's airflow at a given pressure differential on a flow bench. Likely, it's at 26-28" vacuum. Just because they will flow that at around a 1 bar pressure differential doesn't mean they won't still cost power. Ultimately, what you're shooting for is minimal vacuum in the intake at WOT. If you have a way to read the factory MAP sensor or if you have a boost gauge, it's a pretty easy measurement.

    In one test I saw, a 90mm TB picked up 14hp on a 331 and made extra power throughout the ENTIRE power band. I expected the 75mm TB to make just as much power until maybe the very top of the powerband. Here's the article from dyno proven small block ford performance:
  12. Sounds kind of Kinky......
    Grabbin' Asphalt likes this.
  13. Gettin' Fresh with a 5.0 :cool:
  14. Kinky is the way I go. I have a 70mm tb, and I think it's actually a 77mm maf. Vacuum is 0 in the intake all the way to the red line with 192cc heads. I'm sure it would be 0 with 205cc heads.

  15. Kurt, what do you make of the article posted?
  16. My understanding is that I'm limiting my ultimate HP/TQ potential with the Ecam and the tubular GT40. The intake will stay, but the cam might find it's way back on my shelf if picking a new custom/off the shelf cam is worth the $$$. What cams would work best with my set up, and what kind of improvement could be expected?
    Thanks again,
  17. I like these kinds of discussions.

  18. I suggest the XE264R-12 and you should be 300rwhp+ with good streetability, this is the cam I want!!!! :cheers:
    #38 Grabbin' Asphalt, Sep 21, 2013
    Last edited: Sep 21, 2013
  19. .55x/.560 lift; 224/228@.050"; 111LSA,

    That was my custom with AFRs and a Cobra intake.
  20. One more thing pondering is to port my intake. It might already have been worked on. Is there an easy way to tell? I will post some pictures later today. Just curious what kind of gains I could hope for.