[WreckerX5d]

I got a new meth injection controller (Torqbyte) and have been running some logs with a map I created. I am basing the injection off boost and RPM, beginning from 20 PSI and also 2500 RPM. The system is 2 500CC nozzles, with begin duty percentage of 30, and maximum is at 40 PSI. 70% ratio is used as well.

On 3rd gear pulls, I've logged that the turbo pressure begins at 36 PSI from 3k RPM, then linearly drops to 28 PSI at 4.9k RPM. This hasn't happened when I am not spraying methanol.

Would the EGT's be going too high and power is cut? I actually haven't checked them when I am going full force on the car.

[kydiesel35]

Interesting. Maybe need to get your boost up and full duty earlier.

Here's my current graph, runs spectacular throughout.

[335dlci]

I have the unit also. I have been getting a long crank. Anyone know how to stop it?

[kydiesel35]

Lots of guys on here get long cranks/hard starts with meth. If your spraying heavy all the time this will happen (especially without a non meth clear-out pull) I've noticed if you bring the boost up with adequate rpm you'll see these problems virtually disappear. I'm running the hybrids but your graph should probably look similar to mine.


I see a lot of people injecting at lower boost (which is fine for Cbu cleanup) but hard starts will be more evident since less WM is properly combusted.

[JOHNNYBRAVO1]

Matty, do you think you also have pooling of extra meth sitting in the IC?

[JOHNNYBRAVO1]

Matty, maybe you have to turn 1 nozzle 4clicks clockwise the other 4 counter😜😜😜😜😜😜😜 sorry inside joke guys with matt

[TDIwyse]

Originally Posted by 335dlci

I have the unit also. I have been getting a long crank. Anyone know how to stop it?

Do you have a solenoid or check valve? I had used an AEM nozzle with built-in check valve for awhile, and had "long cranks" due to what I believe was leaking issues.

I switched to solenoids placed close to the nozzles, which in my testing had very similar improvements shown in this video. This eliminated the long crank start issue for me.

[335dlci]

Mtysolenoid is about a foot away from my nozzle. Maybe my solenoid is leaking internally. I know it drips frpm my connection to externally. Second one I have purchased already. Will be switching to a snow performance unit.

[WreckerX5d]

Originally Posted by kydiesel35

Interesting. Maybe need to get your boost up and full duty earlier.

Here's my current graph, runs spectacular throughout.

I switched maps to a similar one, and made it full spray at 28psi opposed to 34 like before. This seemed to increase boost to 31psi at the end of the RPM.

EGT read 950*f by the end of the pull as well.

[WreckerX5d]

I monitored this again at the track last week. So far the results were..

2nd-4th gear, 34psi sloping to 31.5psi

5th gear, 37psi to 35psi.

EGT on the runs were 400*f and 1050*f at the end.

Coolant temps were 165*f to 192*f at the end.

AFR's hovered around 13 to 14.5 the entire time.

Am I over thinking this? Or are there some things I am uneducated about and need to research more into. The increase in pressure for 5th gear is something I am not understanding.

[TDIwyse]

Originally Posted by Wrecker335d

I monitored this again at the track last week. So far the results were..

2nd-4th gear, 34psi sloping to 31.5psi

5th gear, 37psi to 35psi.

EGT on the runs were 400*f and 1050*f at the end.

Coolant temps were 165*f to 192*f at the end.

AFR's hovered around 13 to 14.5 the entire time.

Am I over thinking this? Or are there some things I am uneducated about and need to research more into. The increase in pressure for 5th gear is something I am not understanding.

It would be helpful to log your CACT's and see what they're doing. On the intake side after the intercooler and/or water/methanol injection cooling, as the CACT's increase, it will require more boost for the same amount of airflow.

As an example from my logs of the 1/4 mile (http://www.e90post.com/forums/showpo...0&postcount=20) you can see that my boost also rises as the gears increase (3rd is higher tha 2nd, 4th higher than 3rd, 5th higher than 4th), but the CACT's are also rising. I can take these logged parameters and put them into matchbot and see that the airflow in lb/min is basically the same for all these gears at a given rpm, even though boost is different. It's the CACT affect that is balancing the boost change.

So, the evaporative cooling of the water/methanol injection can definitely impact your boost readings, because it can have a big impact on your CACT's.

Note: If your water/methanol injection nozzle is not in front of your CACT sensor, you won't be able to measure the CACT reduction benefit, and that will screw up your use of matchbot (or other engine simulator) because you won't have the correct CACT info.

[335dsleeper]

How are you measuring boost pressure? Torque app or an aftermarket gauge?

[WreckerX5d]

@TDIwyse CACT did not go above 130*f. I monitored it but did not log during the pulls. I haven't researched it but would that much temp increase over the 65*f ambient equate to the psi increase?

335dsleeper I monitored boost via the torqbyte log software, which is directly pulling the reading off the cold side intake pipe.

[TDIwyse]

Originally Posted by Wrecker335d

@TDIwyse CACT did not go above 130*f. I monitored it but did not log during the pulls. I haven't researched it but would that much temp increase over the 65*f ambient equate to the psi increase?...

Well, just looking at the "max" CACT isn't very useful. You would need data at each rpm.

For example, using matchbot and taking one of my top end data points at 4862 rpm and then comparing the impact of a ~42.5 deg F increase in CACT (100 vs 142 F ... tweaked the IC efficiency to do that), shows the engine would need ~4.5 psig more boost to still flow ~64.6 lb/min of air.

[335dsleeper]

Have you tried verifying boost drop using a mechanical gauge or torque app?

Maybe the torqbyte sensor is getting saturated or something.

Originally Posted by Wrecker335d

@TDIwyse CACT did not go above 130*f. I monitored it but did not log during the pulls. I haven't researched it but would that much temp increase over the 65*f ambient equate to the psi increase?

335dsleeper I monitored boost via the torqbyte log software, which is directly pulling the reading off the cold side intake pipe.