more sputtering

[cleatus12r]

Originally Posted by stlhrse

yep I remember now. You are correct

Does the 87 tow use the same fat fuel tables as your 87 tow tune? If so, is it possible to trim those down to the 87 performance level?
I appreciate the quick responses

Doug

Yes, and I will be making that change.


By the way, how well does the C87 Tow tune you have work or have you run that one yet?

[stlhrse]

I have run it, but not towing yet. It seemed to do OK, for the short amount of time I drove it. If you don't mind, maybe after we get the performance tune worked out, you could just make the towing changes to that one. Don't do anything to it yet though cause I'm not going to be doing any towing in the next month or so for sure. I'd want to have the tranny strategy and throttle response from the edge, but more timing and much firmer shifts. I appreciate your help.

Doug

[BigSur]

Can I step in here for one second?

Cody....is my last tune upgrade "close" to what you've done for stlhrse? In reading this thread, I realize that not only do I have the same issue, but the same goals. For the most part, I LOVE the way the canned 87tow runs.....was just hoping the performance would give me even more "pep". Alot of what you guys are saying here is over my head though

I haven't ran my newest tune yet....just wondering if you've made similiar adjustments.

I don't want to step on this thread....I will contact you directly via chat when I get some time. Thanks for taking the time to deal with all this.

[cleatus12r]

Doug,

Try this new custom 87 Perf.

Greg,
We'll see how Doug's works out. He has a very different HEX than you have, but it shouldn't take much to get your kinks worked out.

[stlhrse]

OK cool. I'll flash it as soon as I get home this evening.


thanks,
Doug

BigSur, I agree. I read your thread the other day before I started this one, and your problems did sound a lot like mine. Hopefully we can get something worked out on mine cause I know how frustrating it can be.

[stlhrse]

OK, so I flashed the new 87 performance tune, and the tranny strategy felt MUCH better. I then started incrementally increasing timing one degree at a time. I don't know if it was necessary, but everytime I increased timing I flashed back to stock then changed it and reflashed. Anyway, I'm up to 5 degrees of additional timing, and it's running great. I'm not really worried about detonation or anything since it's not on juice or a blower. Although I haven't noticed any performance decreases, I am concerned about the knock sensor pulling timing without me realizing it, if I get some bad gas or something.
Cody, is it possible in your software to disable the functionality of the knock sensor, so it can't pull timing on its own? I use SCT software to tune my racecar, and though its an 02 so it never had a knock sensor, I know that there are quite a few things in there you can just disable. I just don't know if the software you guys use does that, or if it does, if the knock sensor is a switchable value, but it would be nice if it was.
Granted I have only been running it for a few days, but I haven't noticed any sputtering or bucking or anything. It feels really good so far. So, I'll continue running it and we'll see what happens. Maybe by Friday, if there are no problems we can wrap this up.

Thanks
Doug

[Jackpine]

Disabling the knock sensor is a great way to destroy your engine. If the PCM was pulling timing, it would pull more than necessary. You would not hear "ping" of course, but you would not have the power you want either.

I think if you actually HAVE advanced the timing by 5 degrees, the PCM is compensating.

At this point, I don't know what your goal really is, and I'm not sure PHP does either. You should not have to change the timing in a custom tune.

- Jack

[stlhrse]

Jack, I am fully aware of what the knock sensor does and how it works. I think Cody understands what I am trying to do, and what my goals are. I've been building engines and doing mechanic work for 20+ years, as well as I'm also a Mechanical Engineer, and a little bit of ping, although certainly not a good thing, is not going to "destroy" my engine. What did performance minded people do before knock sensors, way back in 2002? Or the stone ages way back when when cars had distributors that you actually had to turn to advance the timing......Stop being dramatic, and now I'll politely ask you to keep your opinions to yourself and but out. Custom tunes are not sacred cows. Cody made the comment the other day that he was getting close to stock timing curves on my old tune, so I expected that his timing curve on this new file might be a little conservative. So I upped the timing, and have been very pleased with the results. Let me be clear, you don't need to know what my goal really is. You're not the tuner.

Cory, please let me know if it's possible to lock out the knock sensor's adjustment. By the way, I expect that the timing that is added to the tuner when I modify the tune is a global modifier, that adds 5 degrees to the whole curve, correct?

Thanks,
Doug

[Jackpine]

OK, this will be my last post.

Doug, I understand exactly what timing does. I have a degree in Aerospace Engineering, about 2 quarters short of an additional degree in Mechanical Engineering (from Georgia Tech) and a Masters in Computer Science. I taught courses in computer programming and embedded systems design for 20 years. I've been playing with cars since the late 50s. I have a TINY bit of knowledge here.

A 5 degree advance in a custom tune sounds like the wrong approach to me. However, I've been wrong in the past and am quite willing to be proven wrong here. I've got no "stake" in this. It's your truck and only YOU know what's really happening with it. I didn't think I was being "dramatic", but I tend to err on the cautious side.

I wish you well. I will only reenter this thread as a Moderator. (And, you are free to post a last word, telling me again to kindly butt out (go to hell?)).

- Jack

[PhqChevys]

Originally Posted by stlhrse

I read the other threads on this issue. Mine is an 05 FX4, and it mainly does it at part throttle cruising whether on the highway or on city streets. I also have tried going back to the stock tune, and the problem goes away. There cannot possibly be anything wrong with my truck if the problem goes away with the stock tune. Also, my converter lock up is lock out until around 80 mph so I know it's not that. It feels almost like a dead miss or not getting enough fuel because the truck just noses over and sputters. If I let off and get back in it, it's ok, but it's incredibly annoying. I've tried a few times to call, but can't seem to catch anyone during phone support hours. I'm fully aware that they are busy, but ......

I'm starting to get a little irritated because I asked for an update to my 87 performance custom tune about a month after I got it, and waited almost two months to get the updated tune. Again, I know they're busy, but may be a good time to hire additional staff to support the amount of business they have. I assume I could go back to the edge canned tunes, but I paid extra for the gryphon, plus the cost of the tunes, and I want a product that is much better than the canned tunes, not just slightly better or about the same, but different. I would like Bill or someone to help me work this out so I can be happy that I spent the extra money to get a gryphon.

I am having the same problem with my truck. My truck does the sputtering with all my custom tunes (87 tow, 87 performance, and 93 performance) but runs perfect on the stock tune and the canned tunes. I'm also thinking about abandoning my custom tunes and reloading the canned tunes. I thought that it was just my truck until I found these threads on PHP's forum. It actually makes me feel better to know that I'm not the only one...

Keep us posted! If Bill finds the cure, sign me up for the antidote!!