Engine Cams???

Discussion in 'SN95 4.6L Mustang Tech' started by Jnicho, Feb 8, 2013.


  1. Jnicho

    Jnicho New Member

    Joined:
    Feb 7, 2013
    Messages:
    12
    Likes Received:
    1
    Trophy Points:
    3
    Location:
    Kansas City, Missouri
    I just picked up a 98 GT vert. I don't know any history on the car. What I do know is it is super clean and low miles. It is my guess this was someones weekend toy not a daily driver. As for mods I'm pretty sure it has a cat back setup. The exhaust note is too loud and too mellow for the stock exhaust setup. I have not been able to locate a name or logo on the exhaust, but the mufflers are very "square" vs. the typical oval shape it that tells anyone anything. There is also a cold air intake on the car and a few chrome bits under the hood as well as some stainless braided hoses. All this brings me to cams. The idle is a little rough...a very slight lope at normal 500-600 RPM idle. It's not as noticeable on a cold start-up, but the computer bumps the idle closer to 1000 RPM when cold so it's hard to say for sure. If I pulled up beside this car I would guess it to have a very mild performance cam in it (or cams as the case my be). There is no indication of anything else causing a rough idle...no stalling, hesitation, etc. So, anyone have any thoughts? How the heck would you tell if aftermarket cams had been installed? Even if I pulled the valve covers I doubt I would be able to tell.
     
    #1
  2. Jhussey1280

    Jhussey1280 Member

    Joined:
    Jan 31, 2012
    Messages:
    179
    Likes Received:
    4
    Trophy Points:
    19
    Location:
    New Pal, Indiana
    It's hard to ID cams in the engine. Some companies will stamp them on the end where the timing gear or balancer goes, but that's hard to see. If it's lopeing like that at 500-600 rpms I'd say it's probably not a cam upgrade. Every time I've heard a cam change, even a small one, it's been an obvious thump in the idle. When my mustang had stock cams it still had a slight lope in it that was noticable because of the aftermarket exhaust. Ended up being a bad sensor not throwing a code though. hehe. Also if they didn't do a PI swap on it, I doubt someone would spend the $1k on a cam swap. The square mufflers could be Flowmasters, but they tend to be labled. Well I doubt this helped much but it's all I can offer at this time.
     
    #2
  3. Jnicho

    Jnicho New Member

    Joined:
    Feb 7, 2013
    Messages:
    12
    Likes Received:
    1
    Trophy Points:
    3
    Location:
    Kansas City, Missouri
    I'll have to get under the car this weekend and see if there is any "branding" on the mufflers or pipes. I'm with you on the cams in terms of effort and money, but it sure sounds like cam lope. Anyone have thoughts on what else would cause that type of idle. Dirty MAF perhaps?
     
    #3
  4. 1fun281

    1fun281 Member

    Joined:
    Mar 16, 2009
    Messages:
    438
    Likes Received:
    8
    Trophy Points:
    19
    Location:
    Atlanta Georgia
    If they are very square mufflers in more of a box style with close to 90 degree angles they are probably mac flowpaths, are they very deep tone, youtube mac flowpath and compare sounds
     
    #4
  5. Jnicho

    Jnicho New Member

    Joined:
    Feb 7, 2013
    Messages:
    12
    Likes Received:
    1
    Trophy Points:
    3
    Location:
    Kansas City, Missouri
    They do look very much like that...and the sound is very good...not too loud at idle, but very deep when you get into it.
     
    #5
    1fun281 likes this.

Share This Page