[Former_Boosted_IS]

Outside of a piggyback, is there anyway to get a 0-5vdc rpm output on our car? DME? Gauge cluster?

This guy seems to have found RPM info on the OBDII plug:

http://www.e90post.com/forums/showth...nstalling+tach

[RiXst3r]

Originally Posted by Former_Boosted_IS

Outside of a piggyback, is there anyway to get a 0-5vdc rpm output on our car? DME? Gauge cluster?

This guy seems to have found RPM info on the OBDII plug:

http://www.e90post.com/forums/showth...nstalling+tach

Did you try pin 10 on the obdII plug ?

[Former_Boosted_IS]

Originally Posted by RiXst3r

Did you try pin 10 on the obdII plug ?

No because he never popped back in to say what his results were. Have you tested that pin?

The other thing is that it appears he is tapping pin 9 in the picture??

[scalbert]

I wasn't aware of the OBDII connector but the CAS signal should work as well.

[Former_Boosted_IS]

Originally Posted by scalbert

I wasn't aware of the OBDII connector but the CAS signal should work as well.

Sent you a PM.

[Former_Boosted_IS]

Originally Posted by scalbert

I wasn't aware of the OBDII connector but the CAS signal should work as well.

Do you have a wiring diagram that will tell us what pin 9 is on the OBDII plug?

[Sniz]

i'm assuming this is for your meth kit?

[scalbert]

Originally Posted by Former_Boosted_IS

Do you have a wiring diagram that will tell us what pin 9 is on the OBDII plug?

I'll check the WDS tonight.

But the CAS signal is a 5VDC frequency signal and is what most kits need. It is not an analog 0 - 5 VDC; it is a frequency based signal.

[Former_Boosted_IS]

Originally Posted by Sniz

i'm assuming this is for your meth kit?

It is. I am trying to find a source that is not boost to trigger on. We can use IPW, but on Piezo injectors the voltage is through the roof. I basically have the ability to use 0-5vdc RPM data or 12v IPW data. There has to be a way to get 0-5vdc RPM data or something that resembles that.

[oddjob2021]

whats the issue with using boost?

no offence, but IMO using RPM as a progressive source to spray on doesnt make sence.

heres an example: you're on a road course and you're navigating tight esses. you throttle on in some places but brake in others, keeping you're RPM high. if this is the case with your system, it will keep spraying until your RPM's drop no? and you're spraying when no throttle (gasoline) input is there. you can bog your engine or worse!

anyway, what i'm trying to say is RPM doesn't seem like the smart choice for the progression. boost makes sense because when you throttle on low, you don't go above 0 psi... meaning no spraying. when you throttle more, to maybe 6 psi, it sprays a little, just like a little gas. then full on throttle is full boost then full pump pressure to spray.

does what i'm saying make sence FB_IS? or will it not work the way i think an RPM depenedant spray will.

[Former_Boosted_IS]

Originally Posted by oddjob2021

whats the issue with using boost?

no offence, but IMO using RPM as a progressive source to spray on doesnt make sence.

heres an example: you're on a road course and you're navigating tight esses. you throttle on in some places but brake in others, keeping you're RPM high. if this is the case with your system, it will keep spraying until your RPM's drop no? and you're spraying when no throttle (gasoline) input is there. you can bog your engine or worse!

anyway, what i'm trying to say is RPM doesn't seem like the smart choice for the progression. boost makes sense because when you throttle on low, you don't go above 0 psi... meaning no spraying. when you throttle more, to maybe 6 psi, it sprays a little, just like a little gas. then full on throttle is full boost then full pump pressure to spray.

does what i'm saying make sence FB_IS? or will it not work the way i think an RPM depenedant spray will.

Using boost to spray is actually a marginal idea at best. You basically must set your spray so low or you taper at high rpms. Think about it, your boost maxes at 4k-4.5k and tapers massively at redline. So you set the start way down to solve this and then spray equal across the entire rpm range and that is not ideal.

The RPM or IPW / Boost have floors that mean you won't spray unless BOTH conditions are met. We need to spray more when more air is going into the engine at high rpms and we simply cannot due that with boost only.

Trust me, I have tested and logged a lot on this.

[Mr. 5]

If the voltage is through the roof then can't you use a zener diode? Get a zener diode at a rating of 5V.

[Former_Boosted_IS]

Looks like I have a solution. I hope to have this up and running in the next couple of days.

[oddjob2021]

you're right, we all taper at redline with our tiny snails. the only 335 that i've seen shift at redline and have it help is ASR's because of the upgraded babies.

i shift at 6500 RPM and always do because of the lights from the BMW PSW. right before the point in my dyno where boost tapers down a lot. i have my FPP at 13psi and the start at 4psi. so its a good progression.

when i do get upgraded turbos ill bump the FPP to 16psi and bump up the shift lights to redline aswell.

EDIT:

Originally Posted by Former_Boosted_IS

Looks like I have a solution. I hope to have this up and running in the next couple of days.

good luck, i hope your system turns out to be an alternative.

[Former_Boosted_IS]

Originally Posted by oddjob2021

you're right, we all taper at redline with our tiny snails. the only 335 that i've seen shift at redline and have it help is ASR's because of the upgraded babies.

i shift at 6500 RPM. right at the point in my dyno where boost tapers down. i have my FPP at 13psi and the start at 4psi. so its a good progression.

when i do get upgraded turbos ill bump the FPP to 16psi and shift at redline like most cars do.

The only problem with that is if you floor it at 2000 rpms and get above 4 psi, then you will be spraying a lot under 3000 rpms. Second, our boost rises so fast, that you are not progressively spraying anything really. Simply put you will hit 10-12 psi almost immediatley so you go from 0% to about 90% instaneously and that is not progressive at all. That is just not ideal for what water/meth is intended to do.

Boost/RPM based solve this problem. A lot of people have been working with me to contribute to the solution, so we owe a number of people thanks for making this happen.