Progress Thread The Only Part Of A Chevy You Don't Have To Tow (until Now), Into An Sn95.

Discussion in '1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-' started by tannerc91gt, Mar 30, 2014.

  1. 14.0 is not too rich at idle. You want it at close to stoich which is between 14.6 -14.7. Most tuners will shoot for that figure at idle.
    a91what and jrichker like this.
  2. I don't see how 14 is rich. 14-14.7 is where I'm comfortable really. I'd like to idle around 14.7 and pull to 12.5ish. But like you said, it's about where the motors happy.
    But I get what you're saying. The car idles great at 14. The plugs fouled partially because I'm a novice tuner and gave them hell at first and partially because the car popped a fuse twice and soaked the plugs yesterday. Then got worse as I tried to fire it up again 2-3 times.
    I don't try to pretend like I know what I'm doing all the time, if I did I wouldn't have bothered with all this.
    I'm trying to find the happy spot for the idle so I can eventually build an alpha-N table. Keep the car from trying to constantly adjust the idle on me.
    I hope I don't appear as argumentative. I appreciate all the advice I can get.
  3. The wideband isnt accurate at idle because it doesnt have enough air moving past it. Let the car sit for 5-10 minutes idling at 14 and i bet you will have a spot of fuel on the ground where the exhaust exits.
  4. I get that. It was especially impossible to use the wideband with open header and a big cam obviously. But What are you suggesting then?
    If it's idling strong, no fuel smoke or unburnt fuel from the tailpipes and the plugs read clean then can 14-14.5 really be "too rich" for this combo? You have yours idling in the 15s? I guess I just don't follow if you're saying to find the happy spot and it would appear that I'm in that ballpark.

    That's why I've been trying to log enough to build an idle table for <3% TPS and <1200rpm. So I'm not relying on the target AFR table.
  5. I think you're on the right track tanner. I also think that what 90lxcoupe is trying to say is that the sweet spot you're referring to, may in-fact be very near 14.7 AFR even though the reading from the meter indicates that it's 14.
  6. Come on, stab that dizzy and put the tranny in gear.
    TOOLOW91 and Stay Shady like this.
  7. Got my quarter stick. Swapped plugs after work last night but didn't have my laptop to fire it up. I'm finally off work tmrw but only for one day so I probably won't work on it
  8. Yes if you have all of those things and it isn't fouling the plugs then you are all set. My car idles in the 16-17:1 range. But with a sequential ignition and fuel injection setup and a large camshaft, you don't have to put as much fuel in the cylinder to make the car run well. I also had leaks where the collectors and primaries met up so that will not give correct readings on the wideband at lower engine speeds. The point I'm trying to make is that in a perfect world 14.7 might work out, but with a ton of variables that may be out of your control, you just have to work with what you have and just make the thing run right.

    Also, when i was first tuning the car and had it way fat at idle, the thing was idling way high in the MAP table and when i started taking fuel out of it, it came down the MAP and that made things much happier in general, car made more vacuum, brakes worked better, better throttle response... It took some work in the idle cells with my car, and now that i changed throttle bodies i get to do it all over again lol.
  9. See I, being admittedly inexperienced would think to steer clear of 16+ AFR. But I think you've got a really good point. The motor reads about 70kpa right now. Obviously not expecting a ton of vacuum but the car seems noticeably more "wound up" than it did in the car it came from. I am/was happy with how it's been running and I'm not going to shoot for a specific AFR but I think I'll keep pulling fuel out of it because I'm betting you're completely right in my case.
    #330 tannerc91gt, Jun 1, 2014
    Last edited: Jun 1, 2014
  10. Lots of people would say that 16:1 is wrong, but there is usually more to the story. I didn't even want to throw the number out there cause i didn't feel like arguing the point.
  11. That's probably true. I appreciate the advice though.
    90lxcoupe likes this.
  12. image.jpg
    Exciting stuff
  13. nothing like the way a quarter stick sits in a mustang i love it
  14. I prefer this quarter stick over the cheetah (that everyone raves about)
    I had reservations about going auto in the first place but being RMVB and clicking through the gears, it's as hot rod as it gets IMO
    A5literMan and TOOLOW91 like this.
  15. PS. Cars for sale ;)
  16. Turn and burn baby!

    P.s. Where I usually agree with you 99% of the time, I think hot roddin' is bangin gears like you life depended on it. My next mustang will be a 6 spd.
    90lxcoupe and A5literMan like this.
  17. My next project will be back to a manual. I like this MVB auto just fine. But like you said, nothin really compares.
  18. Speaking of selling, there's a 94 cobra near me for $4500. Rio red, staggered FR500s, a/c works. Motor has a strange vibration. Im thinking about it, but I promised myself Id finish what Im working on instead of bailing out early
  19. I definitely wasn't going to let myself ditch it until it ran and I drove it. That was my compromise so that's what I stuck with.
    But my only real goal was to prove to myself I could do it and to build something without cheaping out on parts and I genuinely just like the building part. And it's an awesome car. But I don't really get attached and there's too many other cars I want to drive/build. So I couldn't blame ya a bit.

    I've got it listed and have a few interested but being a half-breed it's not gonna pull the price I need to be ok with selling it. So I'll sell the mustang as a roller and the motor/trans/fuel/ecu/exhaust as a "swap ready" drop out. Someone could buy it and have it running in their car in a weekend.
    It just might be a month or three until I actually move along