2010 Camaro 2.5bar OS Whipple driveability issues

[262]

Ever since we did the 2.5 Custom OS on this car it has been nothing but an absolute headache to get the idle correct and get rid of some tip-in bucking.

Quick run down
2010 camaro Auto
379 CI (3.825 Stroke x 4.067 bore)
~10.5:1 CR
TEA ported LS3 heads
227/240 625/601 113+3 bullet cam
BTR platinum springs
Kooks 1-7/8" headers to 3" corsa exhaust no cats
CAI
Whipple 2.9L 3.25 8-rib pulley
IW 10% OD balancer
ID850's
ZL1 fuel pump
MSD BAP
NGK BR7EF gapped .025
Dual pass Torq heat exchanger
Yank PY3000 converter


Intake system was tested for leaks with both pressure and smoke and none were found. Leakdown test showed less than 8% on all cylinders.

When running in SD mode idle quality is absolutely horrible. Once the motor has any temperature it beings to surge and gets prononced enough to cause stalling. Turn the maf back on and it idles rock solid again like a properly tuned cam'd car should.

While in SD mode car can be driven as long as it is not left to idle long periods of time normal. Can make rips on the dyno and pulls clean to ~7k when we shut down.

Put the car in Blended mode on the dyno or street and all hell breaks lose again. Going from a dead stop or even steady state cruising then to WOT the car will pop/bang/spudder and just overall falls completely on its face. If you slowly roll into it you can get a clean pull. Checked for the "weak" maf and was not the case. The file uploaded keeps the car in blend mode at all times but tried it switching to maf only at 2k rpms no difference.

Attached is the Config and a couple of scans from the dyno session and obviously the tune.


Any insight to the idle qualities and the cause of the tip-in issues?

[edcmat-l1]

What MAP sensor do you have in it?

That's a shit ton of idle air. I'd put that back to stock and start over with that. There's no way it should be that high.

Same with startup airflow. Way too high.

[262]

ZR1 map sensor the "2525" red label

[smokeshow]

Also set your displacement to the correct value... That'll piss stuff off in SD.

[DSteck]

Also set your displacement to the correct value... That'll piss stuff off in SD.

Doesn't matter on E38s.

[262]

Havent found many OS's that it matters and a whopping 14ci difference really isnt a make or break it deal here.

When the Maf is enabled it is wanting just a little more than what is programmed for idle air. Any less and idle gets even worse.

[DSteck]

Your idle timing is way too low for that cam. That's why it needs so much idle air.

[262]

What about the tip-in issues?

[smokeshow]

Doesn't matter on E38s.

Why not?

[DSteck]

Why not?

Gen IV uses totally a different method for volumetric efficiency that doesn't require displacement.

[smokeshow]

Gen IV uses totally a different method for volumetric efficiency that doesn't require displacement.

I see. I didn't know that displacement wasn't an input parameter... One of these days I will dig through Bluecat's stuff

[LT1Z]

Havent found many OS's that it matters and a whopping 14ci difference really isnt a make or break it deal here.

Should be 3ci unless you meant 397 which the BxS works out to +21ci. Of course still doesn't matter on a 38/67

[262]

Too many damn numbers to remember and partially ratarded 379-397 none the less its a moot point in this controller.

[edcmat-l1]

In the breakup log, it looks like your fueling is off bad, and that's why it's breaking up. You're lean as Jenny Craig off idle all the way to when you tip in on it, and it breaks up just because it has no fuel. Your WB shows lean, and your narrow bands too. Real lean.

Can you post a log of it in SD? Have you tried turning your trims back on and dialing in your part throttle with the trims instead of WB error?

[262]

Short terms with the file as is with brand new o2's and confirmed no leaks bounce betwee -3 and +4 and I chase back and forth trying to get them any closer.

I noticed when in OL that anything leaner than lambda 1 the narrows read less than 50 on most car we have tuned and same thing that richer than lambda 1 they tend to just stick at 850-900.

I think I have a log from a clean pull in SD I will go back and check.