Hey guys I need a little help. So I had my cats removed and a true x pipe put in my exhaust system and every since now when coming to a stop mainly when cold it surges but stops when I come to a complete stop most of the time. I don't have a current data log but will get one later today. Does anyone know what's going on with this thing? Built engine with GPI SS3 cam, TSP long tubes, Fast LSXR intake, Nick Williams 103 mm throttle body, and I kept vvt.
Camaro ss3 tune almost final tune.hpt
This is not how your BRAF should be like.
Does this look better? Camaro ss3 tune new braf settings.hpt
Yes
There are so many things that can contribute to that..
A log would help to find out for sure.
Biggest culprits are fueling (typically too rich) or bad downshift timing.
Tuner at PCMofnc.com
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Ok so I got some new logs for you all. This was my first try at it. I set all the braf to the tuners specs.
Camaro ss3 tune new braf settings.hpt
falling on its face.hpl
This is my final attempt at it and it runs ok now no more surging but seems like it hangs a little bit when coasting but I rather it do that then die on me. Because before this tune it wanted to die me coming to a stop. Alls I did was raise the braf about 40%.
Camaro ss3 tune best so far.hpt
best log.hpl
That tune needs a lot of work/help.
You are going to chase idle issues and other driveability problems until you tune the VVE. It really must be done.
Tuner at PCMofnc.com
Email tuning!!!, Mail order, Dyno tuning, Performance Parts, Electric Fan Kits, 4l80e swap harnesses, 6l80 -> 4l80e conversion harnesses, Installs
Unfortunately I don't have the experience to do that just yet.Originally Posted by Alvin
So no one is running a maf only tune that is running correctly or no one has ever corrected a problem like mine just running maf?
you can work with maf only if you wish and still correct these issues. There are better ways in my opinion that just running up the braf to extreme heights. One is to adjust the effective area minimum to achieve a stable minimum throttle opening. Also try these settings in the trans
Screenshot (86).png
So much of my surging during cruise and low speed decel was VVE and timing. I cut timing significantly in the low rpm low airflow areas from stock then matched the idle and decel tables. I also re enabled my DFCO which I always though was detrimental to performance. Doing this eliminated the pops and bangs during decel. ( unless you like those)
Thanks I'll give it a try.
It seems to be a lot better with the tranny settings you showed me. I also took like another 5% or so from the 800-1000 rpm braf. So maybe a little bit of both the combination worked or just maybe your tranny settings. Could you elaborate a little bit on what you did there?
Camaro SS3 Tune best.hpt
It still wants to do it when it's like below 50* outside. Do you guys think that I should lower the braf ECT multiplier 12198 under 50* a little?
So, I tried that and it made it worse so I put it back where it was for the time being. If I lower the braf at all below from 800-1200 rpm it will barely run and I don't get it because that's where everyone thinks I'm crazy for putting the idle airflow that high. So any suggestions on how to get it to stop surging when it's cold outside?
Camaro SS3 Tune best 2 with speed o correction.hpt
short run.hpl
Last edited by morepowerjoe; 01-29-2023 at 05:08 AM.
Try setting back your ETC scalar back to stock. Learned that you don't need to change it for 103 NW tb. I didn't test it yet but give it a try. Then lower your BRAF. Moreover, your VVE tables are stock you have to tune them.
Camaro SS3 Tune best 2 with speed o correctiontry.hpt
Try that and see how she does. Who set the timing table so high?
It was dyno tuned with a SS3 vvt camshaft 646/637 228/246 and for this cam the high octane timing table isn't that high at all compared to others with the same camshaft. If I put in your timing table I will lose all my hp.
I hate to sound like a preacher here but I've been doing this for many years and there's many ways to get to the same results. People saying your base running airflow isn't correct, well it's not correct to them. Many people do things different ways and in the end if it works then roll with it. You're over here changing the braf but it's actually fine because when you change it the car stalls out. The ETC Area looks correct for that throttle as well. If it's running closest to desired with those braf settings then consider making slight changes to the idle adapt. Possibly try mirror opposites from over and under. For example where it says -20 in the over make it positive 20 in the under. It seems close just slight timing tweaks should get you there. Every car is different so experiment with those settings until you get desired results.
Thank you sir.
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