RPM's juming around top of 2nd and 3rd

[musclestang89]

Just curious, could being to rich or need more timing or both cause this? I have been looking at my datalogg files over and over. Man around 5000 rpms it jumps around. Tell you the truth I can feel it in the car. But when I watch it on the datalogg, I just know thats killing my top end. Casue before I would run 105-106 mph all day long. Now I'm having a hard time hitting the 100mph :(



Yook the car out tonight with some nice weather. Heck my intake temp hit 200 only a couple of times. First pass of the trailer it went 6.8@102 it felt good, but my mph wasn't there. And that was with a 1.63 60ft. Almost like my old times. After that it went south, 7.1-7.3 98-99mph with a high 1.7-1.8 60ft. I thought it was spinning, but now I'm thinking it was bogging off the line. Just trying to get it to run back into the 6.7's before FFW and I'm running out of time. Heck I'm running what I was last year, with alittle more mph.


Brandon

[turbostang]

Just curious, could being to rich or need more timing or both cause this? I have been looking at my datalogg files over and over. Man around 5000 rpms it jumps around. Tell you the truth I can feel it in the car. But when I watch it on the datalogg, I just know thats killing my top end. Casue before I would run 105-106 mph all day long. Now I'm having a hard time hitting the 100mph :(



Yook the car out tonight with some nice weather. Heck my intake temp hit 200 only a couple of times. First pass of the trailer it went 6.8@102 it felt good, but my mph wasn't there. And that was with a 1.63 60ft. Almost like my old times. After that it went south, 7.1-7.3 98-99mph with a high 1.7-1.8 60ft. I thought it was spinning, but now I'm thinking it was bogging off the line. Just trying to get it to run back into the 6.7's before FFW and I'm running out of time. Heck I'm running what I was last year, with alittle more mph.


Brandon


Post a screen shot of the datalogs here so we can review them.. :D

[SSMAN]

Ignition issues? Spark running low at high rpms?

[NDSP]

Being to rich can definately cause that. A guy over on turbostangs was having a similar issue and it was because it was too rich.

[musclestang89]

Brooks its on the lab top.


NDSP- that what I'm thinking, but working on LM-1 wideband. We are not for sure which one is the run. We played with it the other day and never cleared it on. So that got alittle confuseing last night at the track.

[musclestang89]

Ignition issues? Spark running low at high rpms?


maybe not enough timing, and had to much fuel casued sprak running low?

[STROKD]

maybe not enough timing, and had to much fuel casued sprak running low?
What kind of gas are you running? I wouls start by pulling about 1/2 a degree per psi on some good gas like 105 octane, and lean the car out till it runs in the 11.8 range on the wide band... You should be hauling some ass then. Let me know what your current tune is, what boost levels at what rpms, and your timing levels.

[musclestang89]

well I'm running 110 gas.


Matt, do you wnat to know what it shows on the datalogg or what I have in the PMS?

[STROKD]

well I'm running 110 gas.


Matt, do you wnat to know what it shows on the datalogg or what I have in the PMS?
Is it 110 rated, or 110 R+M leaded... I don't think you need the leaded stuff, you aren't making enough power... the 110 rated (105) B42 is some great gas, why not switch to that? If you don't have enough timing, you won't burn that leaded stuff, and if the motor doesn't need all that timing, like it isn't making that much extra power with each degre of timing, then you should go to a easier to burn gas, and turn the timing down some...

we need to get that bitch to a dyno, beating on it at the track and this guess tuning shit is for the birds, that's what was done 30 years+ ago with Muscle cars... ;)

Tell me what the PMS shows and what the datalogger is outputting after your settings to see how far its off...

[musclestang89]

I think its rated 110, not for sure on that. I bought it from Rememder(sp) something like that, that carrys race gas cheap. It is the Scooco(sp) whatever, you get the point.

well another thing is my TPS isn't going to 100%. Only like 97-98% through the run. I have been told that my WOT tables might not be working consistent or at all.

Plus another thing its showing I'm mawing the injectors out every now and then. And i know it shouldn't be doing that, casue there still more left in that combo.

[Moose Jr]

I think its rated 110, not for sure on that. I bought it from Rememder(sp) something like that, that carrys race gas cheap. It is the Scooco(sp) whatever, you get the point.

well another thing is my TPS isn't going to 100%. Only like 97-98% through the run. I have been told that my WOT tables might not be working consistent or at all.

Plus another thing its showing I'm mawing the injectors out every now and then. And i know it shouldn't be doing that, casue there still more left in that combo.

Do you have any numbers in the part throttle high load tables? If not, go ahead and put in the numbers from the WOT tables into the part throttle high load tables. That way, if the TPS is not truly showing 100%, your numbers in the high load table should be picked up.

[musclestang89]

Yes I do have #'s in part throttle and high. Are you running the new or older PMS moose?

[musclestang89]

Brooks give me alittle bit and I will. Never done that before :D

Moose- I'm running 42lb injectors. I don't I'm maxing it out, I just think I have way to much fuel being thrown in there and its maxing it out. I might go ahead and go down on the gas to. Heck cheaper gas won't bother me, I was just trying to be safe.

[Moose Jr]

Yes I do have #'s in part throttle and high. Are you running the new or older PMS moose?

I'm running the older version, 02' model. Umm, you might go ahead and try some of that unleaded 105 race gas. Like Strokd said, get that thing on a dyno and tune it. Blind tuning it, especially on a boosted combo, will get you in trouble quick! You said you were maxing out the injectors, what size are you running?

[turbostang]

No dork.. Post a screenshot (picture) of your datalog..

It's easy..

With your datalogger opened.. get the log in question opened up..make sure it is showing the area in question.

Hit the "print screen" button.. (nothing will happen)
....open your favorite photo editor like paint with a "new" document open (blank screen)... Hit ctrl +v (paste) on that blank screen.
... a picture of your screen should show up.. crop out the junk and save as .jpg - then post that bad boy up...

[musclestang89]

ok they are in order, I wonder why my other post when before yall :confused: , hmm oh well here are some datalogg. I can get yall more if you want since I know how to screen shot now :D

[Moose Jr]

You might be cuttin' it close with those 42 lb'ers. I bet eventually your gonna want to go faster so might think about moving up to some 55's or, if you have the injector driver, some low impedence 75's. I'm running 75's and only seeing about 80% duty cycle max with 12 to 13 lbs. of boost.

[musclestang89]

damn you running 75lb injectors. I didn't know that. Yea I know I will have to move up so or later, but we are wanting the car to run like it did. 6.7's @105-106. It use to run that with no problems, but back then I didn't have the datalogg and some other things were alittle weird so we are not for sure on how it was tuned.

1 thing we can remember if the stadalone was on off back then and I didn't have a MAP sensor so it wasn't reading the boost tables back then either. So we think back then it was running off pure 42 lb injectors with no help.

[turbostang]

Why dont any of the tables show the a/f ratio? I'd say that due to the high air temps - is why the injectors are runnning so hard. I'd also say that less timing will make the car go faster. (judging from my personal experiences on my car is why I say this) My air temps dont even get that high with 21 psi and I run 24* It also looks like the MAF is getting close to pegging the flow on it..

[musclestang89]

less timing? Heck I think my car loves timing. Its runing about the same as it did that one night with 32 degree timing. And the reason it doesn't show the a/f ratio is cause its setup to run there wideband but that cost extra. But I got this LM-1 now and working with it.

And the high air temps I thought those temps look pretty good. I think we ware just adding to much fuel is why the injectors is maxing out. And how can I tell if I about to pegg the mass air out? I'm not for sure on how to read that. Its a pro M 80mm.

[musclestang89]

But we have decided to go to the dyno next week to tune it there. Since I won't have any track time till FFW. Hopefully I will drive away with more than what I had the first time and that was 474 and not reving it past 5600. Right now I bet it doesn't even hit the 450 range :(

[turbostang]

But we have decided to go to the dyno next week to tune it there. Since I won't have any track time till FFW. Hopefully I will drive away with more than what I had the first time and that was 474 and not reving it past 5600. Right now I bet it doesn't even hit the 450 range :(


I would be willing to be that you will find with air temps that high that it won't like timing more than ~24-26* max. The MAF flow will most likely peg in the 1500 kg/hr range. You dont want to know what happens when it pegs. :eek:

First and foremost is to find out what the a/f is - then tune it accordingly with "low" timing. After you are satisfied with the tune (and it is slightly rich) add timing and see how it responds. Keep it on the rich side on the dyno (about 11:1) becuse when the load of the weight of the car is imposed on the motor - the a/f ratio will go to about 12:1. (give or take a little)
On my car it gaines about 150* in the EGT's coming off of the dyno and going straight to the track (within 1 hour or so).
Just dont get impatient with the tune and hurry.. you'll wind up with some trashed headgaskets and a cracked block.
(build a turbo and all of your problems will go away :D)

[musclestang89]

thanks for the advice Brooks. we plan on taking it to Speedtek on Thursday, hopefully we will find out alot of answer. From looking at the wiedband and we are still not for sure on which one is the actuall run but its all over the place on the a/f. And this is all the ones they were saved. It looks real crazy, like someone heart beat crazy. And I know I saved at least one full pass , just can't figure out which one it is.

Damn this tuning stuff can get to you. Oh well, it will be worth it in the end.

[turbostang]

thanks for the advice Brooks. we plan on taking it to Speedtek on Thursday, hopefully we will find out alot of answer. From looking at the wiedband and we are still not for sure on which one is the actuall run but its all over the place on the a/f. And this is all the ones they were saved. It looks real crazy, like someone heart beat crazy. And I know I saved at least one full pass , just can't figure out which one it is.

Damn this tuning stuff can get to you. Oh well, it will be worth it in the end.


The resolution in which the graph is saved in had alot to do with how "jagged" the line is, it's probably not as bad as you think. The ultimate way to tune it would be to lean/richen the MAF curve - but I dont think the PMS has that ability.
.... take baby steps with it and you'll be ok. Let me know if I can help.
(pssst - put a turbo on it :D)

[musclestang89]

lol, one of these days I have the turbo. Need to practice with the blower:D

One thing I did notice as I went through the run again, my mass air clims all the ay to 1758 :eek: Is that bad?

[turbostang]

lol, one of these days I have the turbo. Need to practice with the blower:D

One thing I did notice as I went through the run again, my mass air clims all the ay to 1758 :eek: Is that bad?


Man.. I'd seriously be checking into that mess.. I think you'll find that it super duper leans out in that area..does it log MAF voltage?

[musclestang89]

damn you Brooks now you got me all scared about the mass air. Every shift it goes over at least into 1700.

Hell I was looking at one of my older datalogg it went into 1900 :eek: , How do I cure this problem?

[musclestang89]

Man.. I'd seriously be checking into that mess.. I think you'll find that it super duper leans out in that area..does it log MAF voltage?


No I don't see it :(

[turbostang]

damn you Brooks now you got me all scared about the mass air. Every shift it goes over at least into 1700.

Hell I was looking at one of my older datalogg it went into 1900 :eek: , How do I cure this problem?


I am not sure about the PMS - but on the TWeecer you can adjust the max maf voltage which in effect "spreads out " the MAF flow over a wider range thus keeping or helping keep it from this problem.
The only way around this problem is to a. get it recal'd. b. get a bigger one. c. get rid of it and get bigger injectors to go with it.
I'd almost say that it is NOT pegging it rather a bad tune that is makeing it look like it is getting pegged. It would buck like crazy and the a/f would bounce between 9:1 and 15.9:1.

[musclestang89]

I am not sure about the PMS - but on the TWeecer you can adjust the max maf voltage which in effect "spreads out " the MAF flow over a wider range thus keeping or helping keep it from this problem.
The only way around this problem is to a. get it recal'd. b. get a bigger one. c. get rid of it and get bigger injectors to go with it.
I'd almost say that it is NOT pegging it rather a bad tune that is makeing it look like it is getting pegged. It would buck like crazy and the a/f would bounce between 9:1 and 15.9:1.



thats our guess to, its all in the tune, same thingf about the injectors maxing out.