Small engine tune/timing

madmikeismad

madmikeismad

So mad
Joined
Dec 19, 2009
Messages
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Disclamier: Not sure what section this thread should go in.

4cyl 1.9 vw ALH block
10mm pump with 12mm dodge guts
5x.022 injectors
gt35r

Finally got the car back together. Car moves along decent, but falls on it's face over 3k rpm. Was hoping it was timing, and adding timing across the map improved it a little, but I'm not sure I'm adding enough.

The IQ (injected fuel quantity in mg) axis isn't accurate. That's why I'm bringing in so much timing (I think) with lower IQ numbers. The IQ numbers are MAP/boost limited. I've pulled a lot of fuel to keep the smoke down, but now I'm thinking the injectors are so big that the smoke I'm seeing now is just a result of degraded atomization due to larger hole size. I may need to actually add more fuel. Next tune has a little bit added through the rpm/boost range.

My question: Am I running enough timing? Or should I add more? I saw a few maps on google (as reliable as it is) of guys running up to 50* Currently, I'm not getting enough boost to get over about 13* of timing, but I would think that'd be enough to get over 3000rpm? I know on bigger stuff 13* won't get you much over 2k rpm, but I'm not sure how smaller displacement would respond.

This is my current timing map:

1zfjsdu.png
 
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What does your actual fuel qty get to since it doesn't max out? Is there a parameter to tell you how long the injection cycle lasts? I'd say it needs more.
 
JWhite said:
What does your actual fuel qty get to since it doesn't max out? Is there a parameter to tell you how long the injection cycle lasts? I'd say it needs more.
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I'm not sure since the pump was never actually flowed. But on the map, it should be seeing 6-9mg as thats what it would be calling for on the other map that limits fuel off the MAP sensor.

No idea how long injection even lasts. There isn't a measuring block for that, and I am not smart enough to do the math.

You'd say it needs more timing? Thats where I'm leaning. Though not even 5 minutes ago, on an obsolete vw thread on another forum, I saw something about a timing limiter map, that I am not able to access for some reason. I'm still looking into that, as there is a chance that map could be killing my timing regardless of what I request.
 
Can you log anything with this software?

If it's limiting you to 9mg, your timing needs to come in faster in the upper revs. It's only got additional 6° going from 2700-6500. Not sure how fast that motor will spin, or how many revs the pump is good for. I'm assuming it's an inline pump. But running it up to 6500rpm you'd need to dang near double the timing. How's the EGT in the upper revs?
 
Jwhite, pretty sure this is a VP34/VE pump with updated internals.

Timing is timing. Does it pull really well up to 3000?
 
JWhite said:
Can you log anything with this software?

If it's limiting you to 9mg, your timing needs to come in faster in the upper revs. It's only got additional 6° going from 2700-6500. Not sure how fast that motor will spin, or how many revs the pump is good for. I'm assuming it's an inline pump. But running it up to 6500rpm you'd need to dang near double the timing. How's the EGT in the upper revs?
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vp/ve pump. That 9mg is the scale if it was still stock pump and injectors. Really it's much more than that.

I'm trying to turn at least 6500rpm. Your logic is how I see it, but I have vw guys telling me not to go over 20*, for reasons that don't make sense other than higher EGT's, which I'm ok with. Are you saying I should change the map so that timing is more rpm based, and less fuel oriented?


oldestof11 said:
Jwhite, pretty sure this is a VP34/VE pump with updated internals.

Timing is timing. Does it pull really well up to 3000?
Click to expand...

Correct. vp37 I think. Pulls decent up to 2500 (decent for about 4psi because big turbo), slows down until 3000, then feels like it's making about 3hp.
 
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I realize your actual fuel qty is greater than 9mg, but if that's all the ECM thinks it's commanding you've only got 4 columns on the timing table to work with. Doesn't give you much flexibility. More timing should net less EGT, but internal temps will be higher, that's why I was wondering how hot it runs now. Less timing in the 1500-2500rpm rows under higher fueling would help the turbo come up faster. I still don't think a mild lack of timing would make it completely fall over.

Can you max out the MAF/ MAP tables and see if it pulls better/ commands more timing?
 
The MAF map is disabled, but just in case, I already maxed out the values in it. The MAP map is what I added a little bit of fuel to to try out in the next flash. I can't max it out because it will almost stall the car out with the excess fuel, and it's very hard to control with the throttle. Plus its a big smokey ticket waiting to happen. Looks like a puller at the end of the track.
 
I went back through the boost target and limiter maps last night, tweaked a few more things, and still got zero improvement. If someone knows anyone who could look over my tune, and point out where I've messed up, I'd be happy to email it to them.
 
It was bone stock, so small 90hp turbo. I guess you could say it pulled normal? Lol

Sent from my HTC0P3P7 using Tapatalk
 
I've never ridden in one, just wondering if it still lost power after 3k with stock parts.
 
I'm not sure what to think. There has to be a limiting table somewhere, timing should help but I don't see it falling over like you described.
 
Just for giggles, I went out and verified the static timing of the crank, cam and pump. With crank at tdc (via dial indicator), the pump and cam are advanced about .5 degrees. I would call that definitely within the safe range.
 
Yes.

Do you know what the timing limitation of that pump is?
 
JWhite said:
Yes.

Do you know what the timing limitation of that pump is?
Click to expand...

The closest solid answer I got was from Seth, and he said (if I'm remembering right), that it was able to advance about 20* from static setting.

Also, vcds read timing at 25*, at about 3500rpm as I recall. It was hard to look back and forth to the laptop.
 
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