I put down 639HP and 618TQ on a mustang dyno. I talked with EcoBrick Bob since he lives close to me and he has HP Tuners. We can use his HPT Suite to "read" the tune for me to get a file to send you. Never hurts to have a second set of eyes! As I understand it, reading a file does not require HP credits correct? Just trying to save changes requires credits?

 

Just have to read it and save it... No credits required since yiur not "editing" it....
I could always look as well.... Higgs and I are both on Hp tuners literally daily helping people

 

yep, no harm in having us both look at it!

640 at the wheels, you need meth to compensate for the lack of injector (LT1s). I just tuned one around the same power level. PM me (or us) for the email addresses.

 

Just want to throw this in there since you are still having problems. When I had this similar issue I had that spark plug issue I told you about as well as a issue with the MAF connection. The wire was very hard to get connected to the harness because of short length. So during boost the plug would want to pull away which pulled the harness from charge pipe. This let in air and screwed up maf readings. Make sure you have plenty of length in that MAF wiring.

 

These guys aren't far from you. Check them out. They do good work on races cars.

Valone MotorSports
16260 Old US41s
239-872-4309

Its sounds like the problem is in your tune. I see issues like this when only the Start of Injector timing was changed and not much else for fueling.

You have a direct injection motor. What was your WOT Air Fuel Ratio?

 

Definitely not an issue with that. Because I broke out my IAT, I got some extra length on my MAF cable from the breakout harness so there's plenty of slack.

Yes, I know Keith. He actually does not do his own tuning, he has Jeremy Formato do it once a month when he comes down. I've got a lot of faith in my tuner, don't suspect the tune to be the issue myself, but once I get the tune file pulled I can have Higgs and T/A look at it to confirm. I believe my A/F at WOT was right at 12.0. Im still working on getting the compression test done. Last night I pulled a couple fuses for the fuel pump. Not sure if those fuses will be enough to properly stop the fuel flow though. Guess I will find out..

 

Did you try what I told you?

 

Not yet. I'm just getting it put back together from having the valve covers off. I decided to order new gaskets for them since I do have 40K miles already. Figured I might as well do them. Just got them back on tonight. Planning to do a compression test tomorrow for peace of mind. I have a friend that will let me use his HP Tuners to pull my tune for review, though no changes will probably be made to the tune until I go back up to my tuner.

 

Ok so i've got half the compression test done (drivers side). Obviously im doing a cold compression test as opposed to the service manual recommended operating temp test. Thats ok for this test because im looking for significant differences that may hint to a problem and a cold test will show that.

Cylinder 1: 215 PSI
Cylinder 2: 205 PSI
Cylinder 3: 219 PSI
Cylinder 4: 206 PSI
Cylinder 5: 220 PSI
Cylinder 6: 208 PSI
Cylinder 7: 217 PSI
Cylinder 8: 210 PSI

Im surprised the PSI is as high as it is actually. Figured it would be around 175ish. Anyway, its a bit difficult to get the gauge tight in the passenger side plug ports so im going to harbor freight to get a set of shorty wrenches. Been looking for an excuse to get a set for a while anyway. Once I get back home i'll finish up the test and have the rest of the results. Stay tuned..

 

I've updated my compression test numbers in the above post. Also, I did a second compression test with a different tester and most cylinders with that tester came out about 165-170 PSI and were within 5PSI across the board. So, I don't think there is anything wrong there.

I put the new plugs in, gapped them to .037" this time. New plug wires will be here tomorrow, guess they got delayed due to the holidays. For the time being, I put the old wires back on and took it out for a spin. The first 2 times I hit it, (2nd and 3rd gear pull) the car felt great, strong, and did not stumble. The second time, the issue came back again lol. We took video of it the second time, which I have posted below.

Remember, this is with single nozzle meth setup. I am tuned for dual nozzle, but have the second nozzle disconnected for troubleshooting. Haven't put it back on yet.

Also, PLEASE, using your COMPUTER speakers NOT your mobile phone, listen to the sound the engine is making through this pull and you will clearly hear the issue that is happening. On a phone you cannot hear the change in sound.

http://vid556.photobucket.com/albums...a/IMG_1228.mp4

I'm a bit boggled by the fact that the A/F is showing it running SOO rich even with the second meth nozzle disconnected. I figured I would be seeing it run extra lean..

 

Wow, perfect compression has to put a smile on your face!
I vote it's time to focus on the tune parameters. Certainly sounds like something is very wrong. I don't think I'd be playing with it too much until you find the culprit

 

Is that afr in the video (bottom values).... Hard to see.... But I hope not being values in the 8-9 range through the pull

 

yes, yes it is.

I can't figure out why it would be running so rich since I pulled the second meth nozzle. You would think it would make it go lean..

 

Sounds like your tune will be interesting. Let me know when you're able to pull and email!

 

hopefully tomorrow! I am going to call EcoBrick Bob mid morning and see if I can meet up with him to get HPT suite. As soon as I do, you and T/A will be the first to know..

 

I assume you have an extra bung that you have your wideband connected to since you don't have a way to turn off closed loop...

Also assuming this is on the drivers side?? At your power level you need meth for a supplement the for fuel and a single 15gph nozzle would only change AFR about 1 point... I don't recall what nozzle you have

Could always have a bung welded in the other side and retest... Need to send that file to Higgs and I and I could tell real quick what fuel looks like

 

What afr was showing up driving around normal out of boost... Should have bounced around mid 14s.. Was it???

 

I want to say it was somewhere around 10/11, but I am going completely off memory. I know 14's are typically normal in cars usually being 14.7 at idle, and low 14's at cruise..

 

I have ARH headers which have a bung pre-fabbed into the X pipe. It is right at the front of the X pipe where they cross over and is on the passenger side. I started with a single 15GPH, then went to dual nozzle which was a 15GPH and a 10GPH for 25GPH total. Right now I pulled the 10GPH nozzle out so I am back to the original meth setup of the single 15GPH.

 

May have a wideband reading problem?? What WB and does it have a setting to adjust to the "free air" before being placed in the exhaust

Let's say it showed 10.5 during cruise which should be 14.5
Then WOT looked to be around 8.8 on average which would be 12.8 (little lean for FI C7, hence your second nozzle which is around 10gph guessing which would put you close to 12.0)