Just used Boostane - felt a nice difference in stock GT350R

[K4fxd]

I like to run 100 octane on the coyote when tracking. 100 octane will run a 1960's 11 to 1 engine so I consider this the benchmark.

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[TommyBoyDIY]

I've been running 50/50 100/93 octane for some time. The first obvious thing I noticed was like was said. Above 6000 rpm in first gear WOT the wheels will just start spinning even before shifting. Then power shifting into second will obviously just keep them spinning. So in my opinion above 5-6000 rpm you can definitely feel a fairly decent increase in power. Not sure how much but it's fun....

 

[drummerboy]

It was evident in the very first tank on this car that it was pulling timing when under load with 91 octane. It's hard to notice it, too, because it only takes a couple knocks, so you barely hear it. At 94 octane I don't hear it knocking any more on the street. Straight 100 on track.

 

[BEERCHAMP]

I'm confused, is the OP adding Boostane to his Toyota Sienna to get it to 'Chirp'?

 

[nastang87xx]

There are several hard maxes with MBT tables usually being setup as the final do not go past regardless of octane. The knock sensors are only free to add when a gap is present between borderline and MBT/other limit tables. There is rarely any gain past MBT except maybe a feeling of increased response in lower load areas.



agreed. certainly not a stock tune if so or maybe it was read inversed for the KR(-= adding, + = subtracting). or lower loads/transient to OP cam angles etc..


The benefit of having octane to spare is how the tune adds timing and the fact that 93 under certain conditions may be enough, but under others may not be ( and thats without the issues of fuel storage/supply chain etc). The way i see it is consistency is created from having reserve octane.

There are two levels of timing advance from the knock sensors based on recent activity. fast/slow. Also there is a learned octane/knock activity multiplier that raises and lowers borderline based on recent sensor activity (good or bad). think long term fuel trims.

during an event where knock sensors are adding timing, it will advance at a higher rate. once KR detected it pauses (or removes timng) and switches to slower advance rate (assuming the pause or small reduction was sufficient to stop the knock retard). if your throttle input is consistent and long enough, it may hit the end target it was going for, but you will be missing out in the short term. usually during a wot pull there is not enough time.

take 3rd gear, punch it at 2500rpms, borderline has a gap to mbt of 5 degrees from 2000 to 8500rpms. (no other scalars to keep this simple) knock sensors dont hear anything and timing is allowed to add quickly until mbt is reached. so by 3500rpms we have the full 5 degrees added in and riding mbt timing until throttle lift or knock is sensed. if no kr, 93 is enough, no power to be gained from more.

Assume for next pull it hit knock at 4500rpms, KR removes timing to get it to stop and pauses before starting to add again but at the slower advance rate. so we find ourselves at 5500rpms and missing 3 degrees of timing that is now being allowed back in slowly. Above 6000rpms the gt350 and gt usually only allows 1 degree very 6 seconds, vs 1 degree very 1/4 second for the fast rate. so by 8500rpms, we are still missing 3 degrees and as far as we know 93 would have been enough for the higher rpms but we will be doing without for safety (stock tune).

These events chip away at the learned octane modifier. this modifier can be logged to see what its currently at and is a good indicator of how its liking the current fuel. And it takes more timing being removed to stop KR once it starts than it would have to simply avoid it. Ex: takes 1-3 degrees to stop it but if we would have ran 0.5 degree less, we would have avoided it all together.

Been a while since I've been on the forum, this thread was interesting to me. This here seems spot on with my experiences. With SoCal 91 and even 3 - 4oz or so of Boostane, I see my GT350 pull timing above 4500RPM at about 75 - 100% WOT or in a tip in condition where I cross that throttle position threshold. It slowly adds it back in but by the time I hit redline, my car still hasn't added the remaining 1.5 - 2 degrees of retard back. This is both tuned and on stock although the tune allows the timing to be adjusted quicker.

Additionally, based on my own experience just driving the car (and I am no tuner by any means) and watching my nGauge, don't think these 12:1 compression cars like tip in conditions one bit. Because If I do a WOT pull from 1st or 2nd in the mid RPM range, it will hold its timing. I've even had a few pulls where it ADDED almost 2 degrees for the entire run up from 2nd through 4th gear with heavy load/WOT. But if I tip in to WOT in 3rd gear from even 4500 - 5000RPM, the car will pull a bit of timing. To be frank though, I'd rather the car be looking out for itself than blowing a motor.

I use a quick pour of Boostane every fill up so about 3 - 4oz.

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