'86 H.O. EEC-IV Tuning

Discussion in 'Fox 5.0 Mustang Tech' started by dusty58, Nov 18, 2009.

  1. Alright fellas, I really need some help. Got an '86 with speed density. Cam (FORD racing e303) won't pull enough vacuum to have MAP sensor work correctly. Is there anywhere to send computer off to get the eec to tune down the fuel ratios? If so,where? Also, if anyone has found a good way to make everything work by switching to carb, let me know.
  2. why not fix your vac problem instead of dorking with the ecu?

    You can't tune broken...
  3. An E cam isn't very large at all, it should pull plenty of vac at idle for an SD car... I would first look for all possible causes of vacuum loss.

    Leaking gaskets, old loose hose connections, cracked/pinhole vac lines, etc, etc... dont forget to check all the ancillary emissions systems too, as they age they can be a great source of vac leaks.

    A vac res may be a LAST RESORT option, but as above fix whats broken first!

  4. Hi.

    I think that vristang misunderstood you.

    1) If anyone told you and E-cam will work with a stock SD EEC, it's unlikely they are familiar with the SD EEC algorithms.

    2) It is possible to get a new SD tune that will work with the POS E cam. And, yes, IMHO, the E cam is a POS. Well, IMHO, it's a POS in terms of any cam newer than 1990. :)

    3) Good luck finding someone that can do a chip tune for an E-cam on an SD EEC. IMHO, as much as much I dislike going to MAF "for no good reason", IMHO, for you, it would be cheaper, better, and more reliable to go to MAF than to even try to get an SD chip tune for an E-cam over the net, or by anyone that isn't very familiar with the SD algorithms.

    4) If you want to spend $$$ and realistically spend ~1,000+ hours learning about tuning, then you can get a Motes or EETuner and do your own tune.

    Last: SD uses vacuum to determine load. Changing the cam on an SD setup is always very risky! IMHO, there are very few cams that "really work" with the Stang SD setup without a tune. Just because an SD set "runs" with some cam, that does not mean that the A/F ratios aren't all screwed up under many circumstances.

    IMHO, learn to do tuning yourself and stay with SD. Or, go with a MAF setup and you can get pretty good HP results and not have to become a geek tuner. :)

    BTW: If you do your own tuning, it is possible to get 400-500+ HP and stay SD. It's not easy by any means. But, it is possible, and a few people have done it. For me, even in stock form, my Stang had more than enough power for the very crowded Mass and Conn roads.

    Good Luck!
  5. Thats the problem, I've checked numerous times for vac leaks. Used gauges, changed ALL vac lines, rebuilt the engine so it has a new pcv, and checked for any other possible cause. the stock h.o. normally will pull around 15-20 in. whereas this cam only pulls about 12. The vac does not vary except of course when the engine surges. even then the engine only surges when its cold and once it warms up, it's not a bad idle. just trying to work out all the kinks.
  6. Thats the downfall the to the E303 cam. It has no overlap in the cam for one. This hurts vacuum along with the rest of the valve events of the cam plays a part of this also