IAM old but still moving slow you know. Been working the longest on the fuel issue and even written up some articles (posts) as to the cause of it. I have gone from 17:1 at high boost to like 9:1. This proved the concept at 25# stepped pulley boost which is a one time thing for me and my S/C.

Fuel pressure control is key and currently getting some non computer success at dialing in the curves. The Zeitronix approach works as Rob can discuss, but several - many have balked at that level of instrumentation to manage the fuel control circuits.

I posted my Carlisle DYNO boost / F/A readings last year to show the improvements possible. When Rob and I have a easily reproducible design, youll have the chance to tune the f/a with or without a secondary datalogger control to solve most or all of your WOT fuel map needs depending on your level of sophistication.

Woody , the fourth if you will on your list

 

No worries - like the OP said, every modification setup is different.

I only monitor Boost and IAT when on the street. (and I'm soon going to remove those gauges) I monitor AFR when at the Dyno and everything else if the dyno shop is equipped with the STAR system. I know for you drag racers trying to improve between runs it's different.

I can't tell you 100% for sure that I am or am not leaning out a just a TAD momentarily at 20PSI.

In fact the actual time spent at 20PSI is brief. It's not like I hit 6,150 RPM in 4th and hold it there for any length of time before shifting into fifth.

I would love to run my SRT6 at 6,150 RPM in 5th gear for a very long-long stretch of road - but that hasn't happened. Yet. This is why I'm impressed with SLK32Germany's autobahn test results.

I can say; I've never had a CEL since modding my SRT6; Ever. (no - I did not remove the lamp) I've not experienced any type of fuel rail pressure issues. But I believe I will someday with the way I drive - as the OEM pump ages and begins to lose it's UMPH. Then I'll upgrade to the SL55 Fuel Pump.

Even if I was leaning just a tad momentarily at redline - my spark plugs, engine, CEL etc.. show no signs of any damage or impending issues. No performance or driving issues...So why would I spend hundreds of $$ on some complicated fuel delivery modification for an issue that does not exist, or at most, is really a non-issue?

If your SRT6 is cutting out or losing power or burning up spark plugs - that's another issue.

I'm not saying that spending big $$ is a waste if there are huge gains (or decent gains) to had. I just haven't seen them yet. So I have a "wait and see" adittude before I bolt on anymore mods...(except the upcomming mods on my list)... but I'm fabbing them up myself...that's half the fun...

 

My first thought was.... we all have Aero Blue cars... nuff said.....


I have a Zeitronix and Dashdaq II..... the Zeitronix had to go back to check out and I should have it back tomorrow.. then have to find out why it stopped giving me output to the laptop/Dashdaq..... I should be able to get some AFR/Boost readings soon... previouse laptop readings did not show an issue, but I wasnt running WOT at the track....

 

In 3rd gear at 5200 rpm's I start to lean out climbing very rapidly to the 15's and higher without the fuel mods. In 2nd gear it starts to lean about 5700 rpm's. These lean conditions coincide with WOT and boost hitting 19+ psi. I have over a hundred logs and this happens every time the only variable is that at what rpm it starts to lean and this is consistent with DA and how quick I am building boost. Go Woody I know you can find a straight forward fix for this.

 

Have you pulled and inspected your spark plugs?

If they look bad - you could possibly be melting your pistons or valves. That can't be good for drag racing...

 

I just recently changed my plugs and they looked just fine. I get out of the gas if I see my afr's go to hi. This has not been an issue since my fuel pump and fpr upgrade with the zetronix triggering aditional fuel when I need it.

 

I told you I can with the Auterra the only problem I had was recording the data, which should be resolved since I downloaded their patch. When I ran the car full out in 4th I had no lean conditions my readings were off the factory o2 sensors and not using a wide band. Right now I am in the process of supercharging my vet so playing with the crossfire is on the back burner

 

You did, thanks for reminding me, I went back and reviewed our chats. You hadn’t reached 20+ psi which IMO is why you haven’t gone excessively lean like I had. I have the same data logger as you, plus a wideband a/f gauge because our logger can’t perform wideband a/f analysis asis.

The O2 sensor will only show you the excessive lean (17.00) condition, indicated by a drop in voltage from .800ish to .200ish, which is triggered by 20+ psi. It will not show you the acceptable lean (11.8 to 12.8) condition that all of us ::have with boosted pulleys::, that’s why I said to notice these things one NEEDS wideband capable equipment.

Enjoy the vet bro, it’s a beauty!

::edit::

 

Hey, I have an Aero Blue also; I must have one that was manufactured on a Monday or Friday !

Let us know what you’re a/f findings are once its back up and running, if you don’t mind. I believe you will notice the acceptable lean condition, where you’re a/f leans out around 5400 rpm in 3rd (max boost). Example: At WOT a/f will be 11.8, by the end of 3rd a/f will be leaner around 12.8. Those are my numbers but you should see a similar curve.

 

Just speaking for my car, like I said my A/F is 11,9 at redline in 4th and 5th. I have no "acceptable lean" condition. For most accurate A/F reading I recommend an "exhaust temperature corrected" wideband right after the engine. According to my tuner the values can differ up to 20-25%...

 

For my clarification, are you saying you’re a/f is 11.9 from the beginning of WOT all the way through redline?

My wideband is right behind the factory O2 sensor, next to the engine.

 

I'm sorry, my tuner has watched the gauges, I had to keep my eyes on the street. But I think he said A/F was nearly the same all the way to redline. For me most important was a healthy A/F above 6.000 RPM, to be sure, not to risk any damage of my engine on extended highspeed runs.

 

That is very understandable, saftey first! I then suspect that your a/f in lower RPM is around 10.9 since at redline your a/f is 11.9. I think in order to achive an 11.9 at redline, your a/f must begin richer to take into acount elevated boost levels. Since the higher you boost, the less fuel makes it into the cylinders. If you don't mind asking your tunner to confirm what your a/f is in the lower RPM or at the start of WOT?

You have the right idea about making sure you have enough fuel on the top end for those highspeed runs . We can't really do those type of runs State side, well legally anyway LOL.

 

It is only my own opinion, but I think with a correct tune of the ECU and the correct hardware you can achieve your wanted A/F-Ratio across the whole RPM-Band...

 

The ECU has MAP limit at 19 psi. Maybe you can reference my findings.
C32 Fuel-pump flow rates - Page 2 - MBWorld.org Forums

 

Welcome and thanks for posting!

Its late and I will need more time to comprehend your feedback but my inital reaction is hmmm 19 psi, perfect for a 178 or C3 pulley. I wonder where that assumption was made (post 9 & 11).