[Camaro1973]

Originally Posted by SATINSTEEL1LE

I havent been able to rip on it yet really since the last power pull on the dyno was showing it running out of fuel on the low side. Ted basically said dont race it, get the JMS installed then you can run it. So I had to drive it home 60 miles normally after all this...SUCKED!! But like he said at least I was able to drive it home and not have it towed home...LOL

You shouldn’t be running out of fuel on the low side making the power it’s making. What’s the pressure running at on the low side? And what’s he requesting on high side and what are you getting? Also what does your inj pw max out at?

[SATINSTEEL1LE]

Originally Posted by Camaro1973

You shouldn’t be running out of fuel on the low side making the power it’s making. What’s the pressure running at on the low side? And what’s he requesting on high side and what are you getting? Also what does your inj pw max out at?

It’s all there in the log.

[laynlo15]

So the kpa on the low side is about 42 psi. Your at about 15 psi of boost at 204 kpa, did I miss your actual AFR, not sure why its commanding 11.57 which is pretty rich. What size pulley are your running? It comes with a 90 mm right? Or something close to that. I agree with 1973, low side should still be pushing enough fuel on a stock Lt4 fuel system.

[SATINSTEEL1LE]

Originally Posted by laynlo15

So the kpa on the low side is about 42 psi. Your at about 15 psi of boost at 204 kpa, did I miss your actual AFR, not sure why its commanding 11.57 which is pretty rich. What size pulley are your running? It comes with a 90 mm right? Or something close to that. I agree with 1973, low side should still be pushing enough fuel on a stock Lt4 fuel system.

Yeah not sure why it says that. Ted was commanding .82 lambda.

As for the low side, he was commanding 76psi but it was hitting 65psi at redline. Boost is about 16 peak at 6800. He said it wasnt out of the realm of possibility to be dropping low side. Its enough for the high side still, but who knows on a long pull like at the track vs a 5 second dyno run.

The JMS was recommended by Ted to add, and that will solve the low side drop. And from what Im reading its not that bad either. Guys are seeing much more drop and still out there running them hard. But this is cheap safety for this very expensive car.

Heres a better look at the log in PSI.

[KingLT1]

your wideband didn't log. Equivalence cmd or afr cmd isn't actual, that is what the ECU is targeting. You have to have the actual lambda reading to see if actual AFR is on target with what is being commanded.

[SATINSTEEL1LE]

Originally Posted by KingLT1

your wideband didn't log. Equivalence cmd or afr cmd isn't actual, that is what the ECU is targeting. You have to have the actual lambda reading to see if actual AFR is on target with what is being commanded.

Yes I know. I did not have a wideband installed in the car. We used the WB on the dyno.

And I was using my laptop with my MPVI2+ because I had Ted's PID file and layout for vcm scanner. He did not want to share that with the shop doing the dyno runs, so I did it all. I dont have the proset features on my MPVI2+, so we had to log lambda (which we did) via the dyno, so it would show up on the dyno graphs. I would then send Ted's logs to him in the format he likes to read, along with the dyno graph showing lambda.

So we had it all covered. The car is properly tuned, showing .82 basically across the entire range. Its like .81ish in the middle around 4k, but thats not hurting anything.

So yeah we had it covered.

[radz28]

I don't know... I know our combination has a bigger inlet side, commanding .84, a hit from about 55, in 4th, through the end of 4th, around 105, in cooler temps, my low side starts dipping below about 60-psi. My IPW is around 5.5-5.8. High-side creeps down to around 2600.

Just saying he might be close is all.

[KingLT1]

Originally Posted by SATINSTEEL1LE

Yes I know. I did not have a wideband installed in the car. We used the WB on the dyno.

And I was using my laptop with my MPVI2+ because I had Ted's PID file and layout for vcm scanner. He did not want to share that with the shop doing the dyno runs, so I did it all. I dont have the proset features on my MPVI2+, so we had to log lambda (which we did) via the dyno, so it would show up on the dyno graphs. I would then send Ted's logs to him in the format he likes to read, along with the dyno graph showing lambda.

So we had it all covered. The car is properly tuned, showing .82 basically across the entire range. Its like .81ish in the middle around 4k, but thats not hurting anything.

So yeah we had it covered.

I assumed the dyno shop read afr with their wideband, but I would consider getting a AEM 30-0334 wideband installed so you can monitor AFR. You don't need the proset feature with that unit.

[radz28]

Originally Posted by KingLT1

I assumed the dyno shop read afr with their wideband, but I would consider getting a AEM 30-0334 wideband installed so you can monitor AFR. You don't need the proset feature with that unit.

That's what I have and don't have a complaint. I should have connected it CANBUS, but I didn't understand it that well at the time, and I only had the MPVI. Even with the 2+, it should be perfectly fine. I think you have to get the ProLink, though, if you don't use the CANBUS feature, and that's extra $$$.

[laynlo15]

I just have one that's hard wired and comes on when the engine is on that I connect my wire to the Mpvi2 dongle. No gauge, you can't look at the gauge anyway so I just see it on my log after I'm done. .

[SATINSTEEL1LE]

Ill get a WB installed eventually. I dont need one now since its tuned, so I will hold off until the next round of mods. I just want to get that JMS installed so I can rip on this without the lowside pressure dipping.

[radz28]

Originally Posted by laynlo15

I just have one that's hard wired and comes on when the engine is on that I connect my wire to the Mpvi2 dongle. No gauge, you can't look at the gauge anyway so I just see it on my log after I'm done. .

I'm not sure if it's for the same reason I don't look at my gauge either, but usually I'm too busy keeping the car straight and I'm focused on the road that I'm not looking at the WB, lol.

[Camaro1973]

Originally Posted by SATINSTEEL1LE

Yeah not sure why it says that. Ted was commanding .82 lambda.

As for the low side, he was commanding 76psi but it was hitting 65psi at redline. Boost is about 16 peak at 6800. He said it wasnt out of the realm of possibility to be dropping low side. Its enough for the high side still, but who knows on a long pull like at the track vs a 5 second dyno run.

The JMS was recommended by Ted to add, and that will solve the low side drop. And from what Im reading its not that bad either. Guys are seeing much more drop and still out there running them hard. But this is cheap safety for this very expensive car.

Heres a better look at the log in PSI.

If it’s dipping to 66 psi at the lowest that’s fine. Your high side pressure is perfect so it’s sent plenty of fuel.

You may want to re-consider the JMS though if you have any plans for any future mods or ethanol, just sayin. Been there, done that

[MartinLe]

^^^^^Oh yeah. What he says.