Tune sanity check - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Batmanntexas · 01-31-2022, 08:35 PM

Hey all, I'll post this in the tuning section as well....

OK, I helped a buddy out and built him an LS3-based 416 (24X Reluctor) with a Novi 2200, 95-lb/hr injectors, ported 821s, 227/243/.620/.629 @114 cam, 2" LT headers, NW 102mm, 10% OD balancer. This is in a 2002 Corvette, M6 car.
Fuel system is a custom built return style using twin 525lph pumps @58psi.

Anyways, I'm trying to get the tune straightened out and I need a little advice/assistance.

The car has been tuned before, as it came to me with a N/A 416 (spun main bearing). So, first thing I did to the tune was apply the appropriate injector data, and update the MAP sensor (3-Bar) information. It is still currently utilizing the 1-Bar SD VE table.

The car will start right up, idle for maybe 2 seconds and then die....repeatedly. Can't even operate the throttle pedal to keep it going. The WB reads 20.

Here's the strange thing: on one of these attempts, the intake pipe popped off the throttle body. The car proceeded to idle and respond to the throttle pedal (not great, but it did respond). WB read 10, and my eyes and nose believed it.

The intercooler is equipped with a 50mm Bypass Valve that closes ~2 inHg, so in my mind, it should be opened, and bypassing air, at idle.

My assumption is that the VE table and/or MAF table are significantly off and causing my initial issues. Tune is attached.

Thoughts?

Should I just add 10-15% across the board to both VE and MAF tables?

Nmbr1gmfan · 01-31-2022, 09:03 PM

I would fail the MAF and work the VE. Attack each one separately.

cc-rider · 01-31-2022, 09:22 PM

Would agree. Fail the MAF. Tune VE. But…you mentioned a lot in that post that would leave me to think that you need to look at every nut and bolt of that build. Give it the best once-over you can.

eLeSthree · 02-01-2022, 05:36 AM

What did the log say during the start up? Did it have fuel pressure? Did the Fuel trims max out? Which injectors?

Batmanntexas · 02-01-2022, 02:15 PM

Quote:

Originally Posted by cc-rider

Would agree. Fail the MAF. Tune VE. But…you mentioned a lot in that post that would leave me to think that you need to look at every nut and bolt of that build. Give it the best once-over you can.

Thanks for the tip, however I don't know what I posted that led to the assumption that I need to check every nut and bolt of this build....

Batmanntexas · 02-01-2022, 02:28 PM

Quote:

Originally Posted by eLeSthree

What did the log say during the start up? Did it have fuel pressure? Did the Fuel trims max out? Which injectors?

Fuel pressure was steady at 58psi. I'll post the log, brief as it is...

The injectors are Fuel Injector Connection units, 95lb/hr @ 43.5psi (114.3 @ 58psi).

cc-rider · 02-02-2022, 07:53 AM

Quote:

Originally Posted by Batmanntexas

Thanks for the tip, however I don't know what I posted that led to the assumption that I need to check every nut and bolt of this build....

I think I was reading too far into the intake popping off comment.

Batmanntexas · 02-02-2022, 08:51 AM

Quote:

Originally Posted by cc-rider

I think I was reading too far into the intake popping off comment.

It happens

I am in no way saying that I am incapable of making a mistake or two...been there, done that...and I'm sure I'll be there again at some point, I just think my current issue is strictly related to a tune issue, and more specifically, an airflow issue.

More to follow...

eLeSthree · 02-02-2022, 11:54 AM

TB Scalar set and minimum running airflow increased about 10%? I'm not even sure C5s are DBW. Just spit balling...

Batmanntexas · 02-02-2022, 06:12 PM

Quote:

Originally Posted by eLeSthree

TB Scalar set and minimum running airflow increased about 10%? I'm not even sure C5s are DBW. Just spit balling...

TB Scalar has a value, and it's different than the stock LS1, not sure if it's correct though, and the Base Running Airflow has been increased also. It is DBW....

Interesting fact, I pulled a 4.8L out of a 2001 Yukon the other day and it was DBW!! Who knew....?

eLeSthree · 02-02-2022, 08:44 PM

Idle Airflow in P/N is 0
MAF curve is wonky ( i realize you havent gotten there yet)
Closed loop Enable ECT is 260
LTFTs are Disabled

JMI · 02-04-2022, 08:47 AM

Don't bother tuning the MAF, delete it.You'll probably max it out with decent boost. Do the custom OS system and tune it SD.That what we did with those older C5 Vettes. Did some 427's W/YSI with the 2/ 2.5/3 bar setup street cars(depends on the ECM used. 20psi boost a few years back. It's time consuming,But once it's dialled in.Drove and worked perfect. 9 second street cars driven too and from the track. Nothing special now, but back in the day,it was pretty good.

stevieturbo · 02-11-2022, 03:03 PM

You say it's a 24x crank...does it have the correct corresponding 1x cam trigger ?

Slowhawk · 02-13-2022, 10:58 AM

This doesn't tune like the e-38.

maf off,open loop. can leave l-terms if you like to dial in.
All the work will be VE table. 411 pcm's have limiters so you might go into limp mode by injector/ve scale.

Start, take notice of a/f. adjust ve till you get into ballpark . max out ETC predicted airflow table.

They are easy when you get a handle on it.

01-31-2022, 09:03 PM	#2
Nmbr1gmfan Drives: Fast Join Date: Feb 2010 Location: Sarasota, FL. Posts: 410	I would fail the MAF and work the VE. Attack each one separately. __________________ http://www.youtube.com/watch?v=fPvVm...&feature=share New and improved non-violation sig vid!!

02-01-2022, 05:36 AM	#4
eLeSthree Drives: 2011 Camaro SS 6sp Join Date: Nov 2016 Location: Drivers Seat Posts: 1,904	What did the log say during the start up? Did it have fuel pressure? Did the Fuel trims max out? Which injectors? __________________ 2011 Camaro SS---SOLD TMS Dart 427 FED M311s, ESS Tuning G4 Blower, DSX Triple FP Assembly, DSX FF, FIC1300, Mcleod RXT 1200HD, Edlebrock Pro Flo XT 1158whp 1017wtq. 2010 CTS-V A6 - "Stock" SOLD 630whp 658wtq 2024 F-150 RCSB 5.0 4x4 waiting for tunes...

02-02-2022, 11:54 AM	#9
eLeSthree Drives: 2011 Camaro SS 6sp Join Date: Nov 2016 Location: Drivers Seat Posts: 1,904	TB Scalar set and minimum running airflow increased about 10%? I'm not even sure C5s are DBW. Just spit balling... __________________ 2011 Camaro SS---SOLD TMS Dart 427 FED M311s, ESS Tuning G4 Blower, DSX Triple FP Assembly, DSX FF, FIC1300, Mcleod RXT 1200HD, Edlebrock Pro Flo XT 1158whp 1017wtq. 2010 CTS-V A6 - "Stock" SOLD 630whp 658wtq 2024 F-150 RCSB 5.0 4x4 waiting for tunes...

02-02-2022, 08:44 PM	#11
eLeSthree Drives: 2011 Camaro SS 6sp Join Date: Nov 2016 Location: Drivers Seat Posts: 1,904	Idle Airflow in P/N is 0 MAF curve is wonky ( i realize you havent gotten there yet) Closed loop Enable ECT is 260 LTFTs are Disabled __________________ 2011 Camaro SS---SOLD TMS Dart 427 FED M311s, ESS Tuning G4 Blower, DSX Triple FP Assembly, DSX FF, FIC1300, Mcleod RXT 1200HD, Edlebrock Pro Flo XT 1158whp 1017wtq. 2010 CTS-V A6 - "Stock" SOLD 630whp 658wtq 2024 F-150 RCSB 5.0 4x4 waiting for tunes...

02-04-2022, 08:47 AM	#12
JMI Drives: Red Jewel Camaro SS Join Date: Mar 2014 Location: East Coast Posts: 392	Don't bother tuning the MAF, delete it.You'll probably max it out with decent boost. Do the custom OS system and tune it SD.That what we did with those older C5 Vettes. Did some 427's W/YSI with the 2/ 2.5/3 bar setup street cars(depends on the ECM used. 20psi boost a few years back. It's time consuming,But once it's dialled in.Drove and worked perfect. 9 second street cars driven too and from the track. Nothing special now, but back in the day,it was pretty good. __________________ BTR LSX388,AGP Twin Turbo.6L90,GM 9.9" Diff.Fore Innovations Level 4 fuel system.Great fuel economy !!!! 1xxx RWHP

01-31-2022, 09:22 PM	#3
cc-rider Drives: 2010 Camaro SS Join Date: Dec 2006 Location: MN Posts: 1,172	Would agree. Fail the MAF. Tune VE. But…you mentioned a lot in that post that would leave me to think that you need to look at every nut and bolt of that build. Give it the best once-over you can.

02-11-2022, 03:03 PM	#13
stevieturbo Drives: it changes Join Date: Nov 2010 Location: Norn Iron Posts: 1,126	You say it's a 24x crank...does it have the correct corresponding 1x cam trigger ?

02-13-2022, 10:58 AM	#14
Slowhawk Drives: 1999 Trans Am Join Date: Jul 2009 Location: Bridgewater,Ma Posts: 2,017	This doesn't tune like the e-38. maf off,open loop. can leave l-terms if you like to dial in. All the work will be VE table. 411 pcm's have limiters so you might go into limp mode by injector/ve scale. Start, take notice of a/f. adjust ve till you get into ballpark . max out ETC predicted airflow table. They are easy when you get a handle on it.