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The regulars here know that I have often piped up about my favorable experience with the BMS JB4 tuning device, and have shared some nice looking dyno plots in other threads. However I haven't posted up about my experience of adding a BMS meth/water injection kit 18 months ago. The setup hasn't achieved the performance gains I had hoped for, but until recently, there continued to be things to further tweak or adjust, before feeling ready to share my observations. Throughout this, prompt responses and good support from Payam and Terry at BMS was the norm - thanks guys.
The car - '18 991.2 TTS, only mods are the JB4 with meth/water injection, and a Kline exhaust on stock cats.
The kit and install - The 2.5 gallon plastic tank and attached pump, as well as the solenoid, control valve and fittings are all of fine quality. The install went great apart from initially being sent a 991.1 Y-pipe; just be aware .1 vs .2 are not the same. The routing of the meth line from the frunk to engine was per my own ideas, and turned out great. I took a bunch of pictures at install, and hope to later add those to this thread. I have tried several spray nozzles. The kit came with two 7 gph nozzles; I eventually settled on two 500 ml/min (equivalent to two 8 gph) AEM nozzles. The AEM nozzles are remarkable for the degree of improvement in aerosolization of the spray over any other other options I'm aware of.
Variables and data analyzed - I need to emphasize that I live at about 5800 ft elevation, and often drive the car at higher elevations. I did do a bit of testing at 1200 ft. The JB4 app has fantastic adjustability of various settings and maps as well as logging. Before adding meth, I was able to use JB4 Map 2 (+2 psi) on straight 91 pump, and Map 3 (+4 psi) by adding a squirt of E85 for about E25. 93 octane works well on this map as well. My hopes for the meth kit, were that it would lower intake temps enough to allow for higher boost without losing timing advance. I logged to monitor mainly boost levels, IAT and timing correction with the ability to request boost-add over stock continuously variable from 0 to +7 psi. On WOT pulls, I simultaneously logged Dragy for 60 -130 times, and sometimes 1/4 mile.
Boost levels - Since our ECUs are set up to hit torque targets, not a specific boost target, it makes it difficult to tell what the stock baseline peak boost actually is, and similarly hard to tell if the JB4 is actually giving the full requested addition of "+3, +4, +6 psi". But generally speaking, it seemed like the higher the requested boost, the smaller the actual addition. Meaning if I requested +3, +4, +6, maybe I'd see about +3, +3.5, +4.5. I believe this is because the higher the requested boost, the more the ECUs response of "torque target met" can't be overcome. (Elevation was a factor here, the car would hit much higher peak boosts at 1200'.) To help address this, BMS provided me with a new program that "spoofs" the IAT numbers the ECU sees to allow for higher boost. I found that it did have some effect to increasing boost, but that seemed offset by causing a little extra timing correction, and didn't seem to help performance data.
IATs - Sure was obvious the meth/water was working. IATS during repeated highway pulls with no meth were typically in the 140s. Meth on IATs plunge to 80s - very gratifying! Timing correction - with data logs, I learned to look for timing correction of no more than 2 - 4 degrees, combined with a pattern of correction lessening back towards zero while at 100% pedal. So the bottom line became - what is the most boost add I can request and not exceed this goal of minimal timing correction? How much performance gain do I get on my best meth map compared to my best non-meth map?
Results - On Dragy with home DA readings typically in the 6500 - 9000 range, my 60 - 130 on Map 0 (stock) is around 8:45. On map 3 (+4 psi, E25) usually 7.0 for a solid 1.45 sec improvement. On meth map request add +6 psi, gives 60-130 of 6.7, so only a 0.3 sec improvement over no meth. Last week I completed my assessment on a dyno. This one was a different unit than the one I used 2 years ago. Being a Mustang, it is not surprising that my new baseline Map 0 and Map 3 numbers were down about 6% from the old numbers.
First graph shows no meth Map 3, +4 psi, and also with meth on request +4 psi. Both had virtually no timing correction, and not surprisingly are about the same, despite the much lower IATs documents with meth on.
Next is my best pull on meth, with a boost add of + 6 psi. I did have a pull with higher peak numerbs, but the power wasn't as smooth or the timing as clean
Lastly, a busy graph that compares my Map 0 Stock, Map 3 and Map 7 meth.
My takeaways - Although my best meth dyno shows a brief torque peak at 4100 rpm, most of the curve shows about +30 whp and +30 wtq for the meth map over the no meth map. This probably correlates with the modest 0.3 sec improvement in 60 - 130 time. I don't think I would have pursued this project had I expected that small of a performance benefit. I would be very inerested to hear from anyone else that has combined meth injection with their JB4, and see if a lower elevation may be a key benefit.
I believe that the relative simplicity of the JB4 device, without ability to adjust the timing and other parameters like a full custom tune can, leaves it unable to take full advantage of the cooling benefits of meth/water injection. I am happy with my car's performance on the no-meth maps, and might consider removing the methanol kit and retaining the JB4. More likely, I am going to look into keeping the methanol kit, and adapting it to a custom Cobb AP tune. This could involve still retaining the JB4 to continue using it to control the meth system, and perform logging duties.
Very interesting and thank you for the write up. You found a similar conclusion to myself when I played with this on diesels 15 years ago, neat, but not really what was expected, and once you calculated how much you actually needed to carry in a truck over 1000 mile run, not practical either.
Meth seems to work very well for the guys doing short, high load runs when pushing as much boost as possible, anything beyond that really doesn't work.
That's a lot of info and material.. Good stuff. Stock cats are choking your gains. The torque limits are annoying, your findings coincide with mine. If you used your map with the trickery for higher boost and lower elevation you'd hit a torque limit and your car would enter a soft limp mode that can be cleared with an ignition cycle.
I'm on an AP w/o meth, running an FBO map equivalent to E35 but I measure out to E30 (best map I've had). I've been back and forth on going on meth for a while. I've talked to a guy named Walter White, apparently he's got the best meth recipe. I'd rather exercise the option for E85 or higher since meth is bad for you and illegal.
^ Dude, thanks for adding your observations with a side of humor : )
What does the term "FBO" map mean?
As far as stock cats choking my gains, I'm not so sure about that. I expect to see major gains over these #s by going to a custom AP tune. I'm open to moving to sport cats after first seeing what the car can do on the stockers, so maybe I'll end up w some actual data on stock vs sport kitties.
Results are not too bad, the dyno run is very smooth and strong with the methanol running! Once you add a custom flash map, you'll have another 60-70whp on tap.
^ Dude, thanks for adding your observations with a side of humor : )
What does the term "FBO" map mean?
As far as stock cats choking my gains, I'm not so sure about that. I expect to see major gains over these #s by going to a custom AP tune. I'm open to moving to sport cats after first seeing what the car can do on the stockers, so maybe I'll end up w some actual data on stock vs sport kitties.
FBO= Full Bolt On. Header Back Exhaust, intercoolers, Y pipe, hoses, diverter valves etc.
I was under the impression that the stock 800 cel cats were restrictive and caused more heat to linger, no?
I was under the impression that the stock 800 cel cats were restrictive and caused more heat to linger, no?
Certainly there is some power level at which the cfm of stock cats are going to limit power, but at just what power level is that?
I have found very little hard data on the matter, but the closest I've come is that FVD/Brombacher says their in-house testing shows the stock cats flow well enough that there is not an advantage to changing to sport cats until approx 680 awhp, and that changing to their muffler alone raises power more than changing stock cats w basic tune-level power. Forum members have reported they were told about the same by APR. I had a phone chat w Soul in which they told me this assessment is probably right.
So until data is presented otherwise, I'm working with the hypothesis that for my interest in simple builds with tunes at power levels of 600ish awhp, I may as well see how it goes with our well-designed stock cats.
10-03-2022, 03:25 PM
BMS JB4 with Methanol kit added
