injector size?

Discussion in 'Fox 5.0 Mustang Tech' started by Mustang88LXKid, Dec 3, 2003.


  1. Mustang88LXKid

    Mustang88LXKid New Member

    Joined:
    Oct 18, 2003
    Messages:
    28
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Midwest
    I plan on rebuilding my 88 5.0 engine, with mass air along with these mods

    185cc AFR Cylinder Heads
    C&L 76mm Mass Air Meter with Truflow Inlet pipe
    March Ram Air
    CHP Spyder Intake Manifold (with the rails and power elbow)
    Moroso Oil Pan
    new pistons, may new connecting rods
    70mm Accufab Throttle body
    not a drastic cam, (daily driver)
    3.73 Rear Gears
    So my question is what size of injectors should I get using all those mods what should I get? I don't want them to be too small or too big because that can make me lose horse power. So please help me.

    Thank you,

    Matt
  2. TIMMY2734

    TIMMY2734 Founding Member

    Joined:
    May 17, 2002
    Messages:
    1,332
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Queens, NY
    Id probably go with 30.


    Sponsored Ad

  3. stangbear427

    stangbear427 Active Member

    Joined:
    Nov 11, 2002
    Messages:
    2,408
    Likes Received:
    1
    Trophy Points:
    49
    Location:
    New England
    Are you stroking it? Those heads are too big for a NA 302. How much HP are you shooting for? If you know that, you can find out what injector size you need.
  4. mike93lx

    mike93lx New Member

    Joined:
    May 23, 2003
    Messages:
    399
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Hudson, MA
    like stangbear said, the heads are too big for n/a, maybe a set of 165's?

    i'd probably go with a set of 24lb injectors. they should be adequate til you make any more major changes. a couple of musts are a nice adjustable pressure regulator and a fuel pressure gauge
  5. TIMMY2734

    TIMMY2734 Founding Member

    Joined:
    May 17, 2002
    Messages:
    1,332
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Queens, NY
    I kinda assumed he was stroking it. I dont know why after re-reading it. If your not, definitely take the advice of the 2 previous posts
  6. Black331Stang

    Black331Stang Active Member

    Joined:
    Apr 29, 2003
    Messages:
    1,491
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Long Island, NY
    yeah stick with the 165s unless u stroking or putting on a supercharger the 185s are way too big...and with 165s N/A u should be fine with 24#ers...oo and i have a set for sale on ebay right now..check my sig
  7. Black331Stang

    Black331Stang Active Member

    Joined:
    Apr 29, 2003
    Messages:
    1,491
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Long Island, NY
    Ah man thats nasty, what are u thinking :nonono: :lol:
  8. TIMMY2734

    TIMMY2734 Founding Member

    Joined:
    May 17, 2002
    Messages:
    1,332
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Queens, NY
    Somebodys not watching **** now, are they??
  9. JJFIVEOH

    JJFIVEOH New Member

    Joined:
    Jun 11, 2003
    Messages:
    269
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Boca Raton, FL
    Are you guys sick? The 185s are WAYYY not too big for a 302. Stick with the 24# and get a decent regulator. Whoever told you that the 185s are too small, must be smoking crack. Now if you stroke it, the 30# would be a good idea...........
  10. Black331Stang

    Black331Stang Active Member

    Joined:
    Apr 29, 2003
    Messages:
    1,491
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Long Island, NY
    i think u need to retype that for it to be understandable...u say the 185s are wayyy NOT to big? meaning they are OK?? but then u wrote, who told u 185s are too small? too big/small which is it? no one mentioned the 185s being too small. They are way to big for a bolt on cat, which we think he has/will have
  11. JJFIVEOH

    JJFIVEOH New Member

    Joined:
    Jun 11, 2003
    Messages:
    269
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Boca Raton, FL
    The 185s are perfectly usable for a 302. Unless you need to keep it street legal, better flowing heads will not hurt. Unless it will affect the combustion chamber size which the 185s will not. How's that?
  12. stangbear427

    stangbear427 Active Member

    Joined:
    Nov 11, 2002
    Messages:
    2,408
    Likes Received:
    1
    Trophy Points:
    49
    Location:
    New England
    AFR was who told me when I talked to their tech on the phone. In fact, he said that on a NA combo 302 I would LOSE horsepower. To much airflow can hurt, just like too much exhaust, or too much fuel pressure. I'm with everyone else who said get 165's. Mustang88LXKid- check out this page for your injector size Q's:
    http://www.pro-flow.com/tech info/sizing.htm
  13. Michael Yount

    Michael Yount Advanced Member

    Joined:
    Apr 10, 2002
    Messages:
    9,047
    Likes Received:
    0
    Trophy Points:
    77
    Location:
    Charlotte, NC
    It's not that any particular head is too big or too small. However, to take advantage of the big ports/valves on the 185's the engine has to be built to rev. At high rpm is where the larger heads can be used to good advantage (serious solid roller lifter/big spring pressure/non-stock ignition/forged everything RPM). That's also true of the spyder intake he's talking about. The challenge is he says he wants a mild cammed daily driver. With those heads and that intake on 302 cubic inches, low rpm flows are going to have very low velocity, which will likely result in a car that is anything but a fun daily driver. So, Matt, you seem to have some mismatched parts here IF you're trying to build a not-too-drastic daily driver. Take these guys advice - go with the 165's, and I'll add, get a long-runner intake -there are a million to pick from. If you're looking to keep some decent bottom end in the motor I'd go with one of the Cobra/Explorer/GT40 trio. Also, I'd recommend you hook up with one of the pros and get a custom cam. They can educate you as to how these components work best together, which based on your suggested combo would help with your understanding. If you make those changes 24# injectors will be just fine; Perhaps 30's if the car is going to spend a lot of time at the track.
  14. Mustang88LXKid

    Mustang88LXKid New Member

    Joined:
    Oct 18, 2003
    Messages:
    28
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Midwest
    Ok, well I have been reading the MM&FF magazine and they tested 185cc AFR heads on a normal 5.0 block that was not stroked and had a carborated setup. (I don't remember the exact issue but I can look it up). But they recomended those heads because they had over 100 horse bolt on with a new oil pan, carb, comp cam. So would I want the 165's instead, because they don't put out the same output as the 185's, but I would like to see your reponses to this.

    Thank
    Matt
  15. Spyderd68

    Spyderd68 Founding Member

    Joined:
    Jun 25, 2000
    Messages:
    939
    Likes Received:
    0
    Trophy Points:
    26
    Location:
    Syracuse, NY
    The Spyder intake is designed for either High rpm/ high boost/ and or larger displacement engines then a 302.

    Dave
  16. JJFIVEOH

    JJFIVEOH New Member

    Joined:
    Jun 11, 2003
    Messages:
    269
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Boca Raton, FL
    Mustang88LXKID is right. If anyone did actually read the articles. Plus, the stock 5.0 can turn 7000 RPMs on a constant basis at the dragstrip if it is not beaten on the street.
  17. Michael Yount

    Michael Yount Advanced Member

    Joined:
    Apr 10, 2002
    Messages:
    9,047
    Likes Received:
    0
    Trophy Points:
    77
    Location:
    Charlotte, NC
    Kid - you're referring PEAK hp gains; go back and see if they have data on HP/torque down below 3000 rpm. That's what's gonna make a nice daily driver - not peak power. A normally aspirated 302 that makes 450 HP at 6500 rpm doesn't make a whole bunch of torque/power at 1500 rpm. You can't have it both ways - unless you increase displacement or add boost. To get the power/torque down a bit lower in the rev range, you need the smaller heads and the longer runner manifolds.
  18. perkys stang

    perkys stang New Member

    Joined:
    Jan 2, 2000
    Messages:
    7,149
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    PA
    NOTHING LESS THEN 30's...... 24's won't keep up...
  19. stangbear427

    stangbear427 Active Member

    Joined:
    Nov 11, 2002
    Messages:
    2,408
    Likes Received:
    1
    Trophy Points:
    49
    Location:
    New England
    Won't keep up with what?! They will support over 400HP without raising the fuel pressure from stock. You think he's gonna get anywhere near that NA?
  20. JJFIVEOH

    JJFIVEOH New Member

    Joined:
    Jun 11, 2003
    Messages:
    269
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Boca Raton, FL
    STANGBEAR is right. 24s will do as good a job as you will need for NA. If anything 30s will slow you down because you won't be able to back them off enough.

Share This Page