Redline EFI (balancing cold & hot)

[63fiberbuggy]

The basic map that was loaded when I received Redline kit started the buggy; however, cold manners were not the best. I tried for months tweaking on my own & finally went to a performance shop for dynamometer tuning by a professional. Of course, with a 1 day tune the tuner only got to see cold start one time; then focused on getting AFR dialed in over range for vacuum/boosted. Was running great when I left dyno shop; however, next day she won't run good enough to back out of garage. I thought if I feathered it long enough it would warm up & get better; but it didn't. Repeated that for a few days, then replaced tuner's ECU map with the original map & buggy fired right up & behaved.

Anyone else running EFI struggle finding balance for a cold & hot engine? and how did you land on sweet spot?

This pull was several hours into tune, a slow roll 1st to 3rd then spool up turbo; he was able to clean up the little bit of chatter between shifts. And obviously, it ran strong to rev limit. Not sure why it's so far off it won't run cold.

https://youtu.be/LEQ2nEedMpo

[Paul H]

On the dyno it takes me under 5 minutes to tune the full throttle and most of the areas around that then it takes hours tweaking the low speed hot/ cold starting. Tuning is made a LOT easier with certain ECU's and correctly matched parts. Dynos are OK for tuning race cars that are too dangerously fast to tune on the road the best map is created using O2 feedback driving around again massively dependant on the brand of ECU how quick and easy this process is

[63fiberbuggy]

Thanks for sharing Paul. I guess I didn't realize the low speed & cold were so dependent upon how tuner set it up for hot (& WOT). I know he bypassed the O2 sensor in the software, so there was no adjustment factor feeding back to ECU.

Since I purchased complete kit from Redline, I "assume" all the components are correctly matched; however, I do wish now it was capable of learning versus manual tuning. Hopefully I didn't waste $ on this tune & have to essentially start over. Just throwing around thoughts, Redline has a dual-map function whereby you can load two ECU maps, then with a dash mounted toggle switch, move from one to the other. Perhaps I could try a "cold" tune on one channel, then switch once engine comes up to temp.

[Clonebug]

I have been running EFI for over 8 years now and I have found through experience that a tune is very dependent on the driver. What a tuner might set as a good tune on the dyno will not necessarily translate to a good street tune.
I put my buggy on a Chassis Dyno after 4 years of driving and it ended up being very close to a good tune on the dyno. There was a little tweaking that smoothed out the hp and torque lines but all in all it was close. We did gain a little bit of hp and torque at the end but not a large amount.

I'm not sure exactly how Redline works but with MS-2 you tune the VE map when warm and the cold start is based on that map by adding a percentage of fuel based on CLT and time along with IAT to a certain degree.
If your driving tune...especially the idle..... isn't close your warm up enrichment won't be good either.
I don't have an IAC valve for cold startup so I have to give the throttle about 4-5% TPS in order for the engine to start cold. I also do not have a separate idle map but my new MS3Pro does have a separate idle map if I read right.
Idle is driver specific just like anything and each engine is different. Only you can really tune it for how you want it to drive. If you don't have an Autotune feature then it is a little difficult to make that happen while driving. You will then have to log a drive and go through the log and figure out where it needs more or less fuel.
I base my tune on these AFR ranges
Idle 12.8-13.5 AFR
Light cruise 14.1-15.1 AFR
Full throttle 100-150 kpa 12.0-12.5 AFR
150 kpa and above 11.5-12.0 AFR.

All the above works for MY engine...yours might be different.
Post your engine and turbo specs so we know what you;re working with.

What I did on my Fuel map is add a significant amount of fuel right above the idle area. My engine idles in the 85-95 kpa area between 400-1200 rpm when at first cold start. Warm idle is down in the 70-75 kpa area at 800-1000 rpm and has a VE number to give me a 13.3-13.5 idle AFR. It's a pretty small window of bins in the grand scheme of things.
I bump up the fuel in that upper area to richen it up without cold start and it has a second benefit in that it acts like an accel enrichment at cold idle and also at take off in first gear. It eliminated a cough or stutter when accelerating at low speeds. I then tweaked the accel a bit to fine tune it.
Timing can also have an effect on how it runs but that is a whole new level to tuning.
I have run most every imaginable ignition map and finally tweaked one that gives me excellent low to mid range transition and fast and full boost by 3600 rpm.