I wanted to start a separate thread on this to satisfy my curiosity.

I had switched to SD on my 96530706 ROM and everything was working great except a small map/RPM range (specifically about 65-85 kPa absolute/1800-2500 RPM) where the IPW would jump around, drop out and recover very rapidly. I have looked at a few other logs from the 96530006 based Roms and all seem to exhibit this behavior. You can start reading from this page if you would like to see screenshots of my logs.

What I would like to see now are some logs from others running SD on the stock ECU, but on a different ROM. I know there are a few running it. Specifically, I need your log to have some data in both that map/RPM range mentioned above. I want to determine if the jumpy IPW issue is just something specific to this ROM that was overlooked or whether it is something specific to how SD was implemented on the stock ECU. If it's the former, we can look further into this ROM...the latter, we can look into the implementation of SD further to try to improve it.

So, anyone running SD on a ROM other than a 96530006 version, please post up some logs with data in the ranges mentioned. If you are going to do a fresh log, do the following procedure for me:

1. Start at about 1500 RPM and apply enough throttle to keep your boost gauge somewhere in between -5 to -2psi (about 10 in Hg to 4 in Hg) and proceed through the RPM range until about 3000 RPM. That will capture the data I need.

2. Please log at least IPW, and, if possible, map, load, and RPM. Possible additional items may be TPS, Hz, wideband, and STFT, but not necessary. Ideally, for slower logging, just keep the items to a minimum (IPW, map, load, RPM).


Thanks,
Eric

 

Eric I have a huge log I did of my buddies car with SD but it is too big to attach... PM me your email and I will send it to you along with his rom ID

 

Thanks...PM sent. I'm assuming that IPW was logged? That's the most important thing I need to look at.

 

Yeah... email sent

 

Sorry but what is SD????

 

Eric, I posted about this awhile ago. It has to do with the IPW somehow being calculated in conjunction with load. I noticed a stock turbo car of our man Jake go from 97% indicated IDC on the dyno at 431whp to 166% at 438 when converted to SD. I am not sure whats going on but its very strange. I can send that log if you want it but I do not have any driving logs of his car I think. I will look when I get home and send them later tonight if I got em.

aaron

 

i can get some to u over the weekend no car now

i am 88570008. all my timing hits the exact same spot, IDCs look perfect and AFRs match my AFR map identically. car feels a lot better.

^^not sure if this is what your asking - just a noob here.

 

I notice the issue quite badly as well. I'm running the 96530706, but I also tried the 94170015 SD rom and it seemed to be the same. The instant I hit 2500 rpms, it runs perfect; 2400 down to 2 grand or so it's pretty studdery with my boost gauge around -10 to -5 in/hg. Also, I run full-time open loop, and I'm burning E85.

 

I drove through this point today for you. Just to see if I had a jitter or anything erratic going on since I pretty much never drive at that low of an rpm. I tried a few things rolling around in 3rd gear at about 2k rpm. From gentle cruising, to in and out of the throttle slightly.

No problems. So Maft-Pro must clean up it's request for fueling from the ecu somehow from it's internal SD calculation.

96530706 rom

Which leads me to thinking the problem is in the SD patch. I looked at my IPW for anything erratic or drops. And I didn't see anything there either.

 

i can try to get this on the weekend. AFAIK no problems on SD for me.

 

I feel this problem most at steady state low throttle cruise..Anywhere else the car feals great.

 

OK thanks....be sure to hit the RPM and map range that I have mentioned and let me know what ROM you are using. The link in my first post gives good illustrations of the problem. A very jagged IPW just in this particular range. The instant the RPM or map are above or below this range, the IPW smooths out as normal.

My whole point for this thread is to find out whetehr or not this problem is for all SD Roms or just the 96530006 SD Rom. And, if we do find people that truly don't exhibit this problem, then I want to look at the ROMs to see what may be different or a difference in their mods, etc.

I'm suspecting this may be a side effect of the SD mod, but some people just don't drive through or in this particular range that often or are less sensitive to this issue. Only IPW logs will tell for sure. I truly hope that it's just some setting or something in one ROM...that way we may be able to pinpoint it easier to find an ultimate solution.


Eric

 

I wish it was just that particular rom, but for me I know it's not since the 94170015 did the same thing. It was a waste of time getting that other rom all ready for my car just to have the same issue, but at least I know that's not the problem.

 

Yeah, that's a bit disheartening, but good to know. I wonder maybe if the IX roms don't exhibit this problem. I remember John saying that he drove through this range extensively without noticing a problem and rolly a couple posts up is using the same rom that I think John used without a problem. Logs will tell for sure.

I just hope that we can get to the bottom of the issue. I want to convert to SD for good so that I can use my new intake, filter, etc, but I want this issue resolved first.

 

i actually may have this problem

i will post some logs up.

on a different note, can i still use bits to lock the car in open loop?