94 GT 30 degrees timing at idle?

5.0_Dobalina

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So i purchased a 94 mustang that spit and sputtered under load at low rpm's and/or speed. Once I reached 1800-2000+ rpm it ran great. I seemed obvious it had a cam in it as i was also told by the previous owner but he said it was in there when he bought it so its a mystery cam. I've been fixing leaks and all sorts of small crap on this thing for awhile and finally got a moates chip with a tune on it. The initial tune was set for a e-cam and it helped the sputter but didn't fix it as it would still sputter and kick between 1300 rpm to 1500/1600 rpm. The tuner had me send him some videos of it running so he could hear it etc and determined its got a bigger cam than a e-cam as it seemed to have alot more overlap or something. I sent him the chip back and he adjusted for closer to a X-cam as it was explained to me and its definitely better as it only bucks now 1200'ish to 1400'ish then clears up and runs great after that. He adjusted to idle to idle at like 1000-1100 rpm also and as i check the timing i see its at 30 degrees with the spout in.....This seemed oddly high to me does that seem high to anyone else? I dont know what it does once under load as i dont have a quarter horse or anything to datalog. I also spoke with a different tuner and according to him if all i have (as far as i know) is a cam i shouldnt need ANY tuning of any kind. I feel like im chasing my tail here. Any help/insight here would be greatly appreciated. My car has bbk longtubes, stock heads, unknown cam, xpipe etc. Yellow/orang'ish cap/top injectors that say rbs on them.
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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There are so many things here that are unknowns.
Start here:
Read through it so you understand the steps and tools needed, don't assume anything, start at the top and do it step by step, pay attention to the notes that are 94-5 specific.
 

5.0_Dobalina

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May 18, 2021
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There are so many things here that are unknowns.
Start here:
Read through it so you understand the steps and tools needed, don't assume anything, start at the top and do it step by step, pay attention to the notes that are 94-5 specific.
It seems like most of what I read in that was surging/creeping idle. I’m not having either of those issues and I’ve set the tps and base idle multiple times. I spoke with my original tuner last night and he said he believe the stock iacv is only good to about a max of 900 rpm? So with him having set my idle to 1000/1100 the computer is raising my timing to achieve the desired “programmed” idle. I’m probably grabbing a quarter horse from him and a BE from moates so I can make adjustments myself and/or allow my tuner to remote into my computer and make changes that way. My initial fright was seeing 30 degrees timing at idle which was verified to be high from said tuner. Hopefully adjusting the idle in the program or even modifying the iacv like what was mentioned in the link you posted will bring the idle timing back down with the spout in
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
19,872
6,677
193
polk county florida
Yeah, ok
People come all the time asking for advice and then it's 'my tuner (or whom ever) said to do this or that.
This is a classic case of poor planning, not your fault, you just have to try to deal with it.
I think the computer in these cars don't play well with a cam that has overlap.
 

5.0_Dobalina

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May 18, 2021
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Yeah, ok
People come all the time asking for advice and then it's 'my tuner (or whom ever) said to do this or that.
This is a classic case of poor planning, not your fault, you just have to try to deal with it.
I think the computer in these cars don't play well with a cam that has overlap.
My tuner tuned the chip and sent it to me. I can happily post a screen shot of him admitting he set the idle to 1000/1100 because of what he perceived to be a large cam. At his advice I did everything recommended like smoke testing for leaks, buying a brand new maf with a ba3000 calibration to match his tune on the moates chip and even purchased a vacuum gauge which we used in the tuning process. (Was reading really low before the “big cam” tune he gave me the 2nd time). Did leak down tests, new iacv, new tps, new plugs etc. when I posted this topic it was prior to me speaking with him last night about the timing. Is what he says true about the iacv? They are only capable of 900 rpm’ish idle? If so that would explain my high timing I would think. Perhaps the link to the other topic as I stated is on to something about trimming the iacv bridge between the two ports to raise the idle to 1000 rpm. I guess I’ll know more once I get home and dig further into the iacv trimming.
 

5.0_Dobalina

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May 18, 2021
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I'm not saying he is wrong, the issue goes back to the 'unknown' in unknown cam.
Oh I agree 100%. My original question was the 30 degrees at idle and has now evolved into does the iacv actually have a “max rpm” that it can achieve at idle without the ecu/pcm/eec having to adjust timing to reach said rpm? I guess I could set my base idle to 1000 rpm then reconnect the spout and see if it drops the timing since idle will already be 1000. I know it’s hard to tell until I see inside the program so it’s all speculatory. The car idles just fine and right where the tuner set it so I guess the computer is just doing what it has to in order to reach that desired rpm.
 

5.0_Dobalina

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The IAC valve is non functional if the tb blade is open like it needs to be for 1k rpm idle,
So then trimming the iacv divider with a dremel like the other article/post mentioned would be the solution for that then so the tb blade is negating the iacv. It will allow more air to get through even if the iacv was totally maxed out. Kinda anxious for the QH to arrive so I can see what’s going on more in depth.
 

5.0_Dobalina

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I’m preparing for my new QH and software to arrive and figured I’d do another smoke test to check for any vac leaks and found smoke only came from my oil dip stick after about 5 minutes. Anyone had that happen before? Is that a bad sign? I figure it’s probably alright as smoke makes it’s way into the oil passages of the motor and works it’s way down then back up the dip stick.