Wayne H.
'91 Dodge Spirit ES 2.5L turbo 5spd
'05 PT GT 2.4T HO autostick (RIP)
'89 Plymouth Acclaim 2.5L turbo auto, "Slugmobile" yes, THE Slugmobile!
'89 Dodge Caravan SE 2.5L turbo auto, "Mean Mini" yes, Gus' Mean Mini! (Current best 11.699 @ 114.43 mph! - Oct 15th, 2022 Cecil County Dragway, MD)
MeanMini dragracing videos: https://www.youtube.com/playlist?lis...URZLB1RxGYF6vw
and other cars, trucks and motorcycles
https://www.youtube.com/user/SlugmobileMeanMini
Yes it is a PM/LM setup. I don't really get it either, I have tuned a couple other LM cars that were closer to stock but they were pretty close to the tables. It is like it is not scaling the tables right but I don't know why and I don't really have much to compare it too either though.
I was about to suggest trying the way you just did. But I'd say something is off. We'll see what wowzer finds. I haven't run into your particular problem before (not to that extent) so could be something with the new MP Tune update.
Latest update, it runs great why the tables are off I hope we figure it out but it is pretty close.
The two things it still has going are when it is cold it is way to rich like in the 9.2-10.0 range till it warms up. What tables do I need to adjust the fuel when it is cold? Second when it is warm and shut it off for about 10-15 min fires up lean till it is back down to operating temp?
After slapping some highz 36pph injectors in my wife's 2.5 T1 and it being insanely Rich even at 19 PSI base fuel pressure I'm excited to see people talking about injector latency. That is something that I have not thought of when thinking of turbo Dodge guys. I always wondered how people dealt with having non stock injectors while using original engine manufacturer data. Probably why people's cars ran so bad for so long in certain situations or people were constantly messing around with fuel pressure. Wrong dead times can mean your injectors might be close at 1 RPM and off at another Etc. Even my FIC has a crude adjustment. Not incredibly important to have the latency perfect at voltages you rarely see. It you could lose a motor if the alternator stopped charging...
Last edited by Ondonti; 09-02-2017 at 02:17 AM.
Brent GREAT DEPRESSION RACING 1992 Duster 3.0T The Junkyard - MS II, OEM 10:1 -[I] Old - 11.5@125 22psi $90 [U]Stock[/U] 3.0 Junk Motor - 1 bar MAP [/I] 1994 Spirit 3.0T - 11.5@120 20 psi - Daily :eyebrows: Holset He351 -FT600 - 393whp 457ft/lb @18psi 1994 Spirit 3.0T a670 - He341, stock fuel, BEGI. Wife's into kid's project. 1990 Lebaron Coupe 2.2 TI/II non IC, a413 1990 Spirit 3.0 E.S. 41TE -- 1993 Spirit 3.0 E.S. 41TE -- 1994 Duster 3.0 A543 1981 Starlet KP61 Potential driver -- 1981 Starlet KP61 Parts -- 1983 Starlet KP61 Drag 2005 Durango Hemi Limited -- 1998 Dodge 12v 47re. AFC mods, No plate, Mack plug, Boost elbow -- 2011 Dodge 6.7 G56
the times below will differ based on which factory calibration you start with.
curve A and C are your short term fuel enrichments. from when the car is started for a certain period of time.
curve C is the shortest around 7 seconds active and then tapers off for around 7 seconds.
curve A is a little longer.
Cold: around 90 sec active and tapers off for around 22 sec.
Hot: around 15 seconds active and then tapers off for around 10 sec.
Curve B - active all the time.
it depends on what happens immediately after starting. if its really rich or lean but cleans up after a bit then the short term enrichments may need an adjustment..
if its rich or lean the whole way till it warms up (or cools down) then its probably curve b that needs an adjustment.
Brian
Originally Posted by turbovanman
for the longest time most folks ran either stock, +20 or +40 injectors. +40's had a table defined from the factory in the S60 cal. dunno how accurate it was but my stuff always ran better when using that table for +40 injectors.
it seems to affect idle alot though as the pulsewidth on huge injectors is so small that the latency may be a significant percentage of the commanded pulsewidth.
Brian
Originally Posted by turbovanman
I just wanted to follow up on this.
I talked to quite a few of the random folks that I've run into over the years that had a lean problem with really large injectors. Most of them scaled up the 3 map fuel tables and then adjusted peftbl to dial the fuel curve in.
Prior to my current setup and just about everything I made Cal's for were +20s and +40s which were pretty straightforward to dial in. 72lb on up? Not so much.
I did some testing on my car with 75lb injectors. It's pretty happy right now with them scaled to 72lb.
That means with large injectors and MPTune, we are going to have to scale them less than their actual size and that the afr calculated values are going to be incorrect.
I'm going to do some more scaling tests over the weekend with an ostrich and o2 feedback disabled.
Brian
Originally Posted by turbovanman
Here's another thing to note: If you run Hi-Z injectors on a low-Z system (like ours), the injector latency that the manufacturer gives will be meaningless. Our system uses a 'peak-and-hold' injector driver which hits the injector with a high current, and the settles to a lower current - to reduce the latency. Newer Hi-Z systems don't do this, the injector itself is designed for a lower latency.
So, if you use a newer Hi-Z injector with a peak-and-hold driver, the latency will be VERY low. In fact, I would simply set the latency table to maybe 1-bit above zero above 12v and call it good.