stock boost

[Papa C 2000]

Logged my IRL for the first time...seeing a peak of 196kPa. Pretty solidly always hits 192-193 kPa before the dip near 6000. Is this consistant with a stock vehicle? Atmospheric today was 101.5-101.8 kPa FWIW. Seems healthy for a stock pulley...a bit over 13psi?

[laser_racer]

You have stock exhaust on the car or has anything been replaced?

[Papa C 2000]

The whole car is stock ATM.

[Astral]

13 PSI stock. 15-16 PSI when your StgII.

[GMRedline]

That dip is to prevent you from blowing your engine. LEAVE it alone!!!

That is why GM stock dyno graphs look like this.



Notice how the HP and TQ flatline? The Stock pulley maxes out the stock injectors without that dip.

Read this thread.

Stock Injectors Stock Pulley Stock Tune and all the bolt-ons

Originally Posted by GMRedline

34s / 3.35" / Stock Tune

This is a stock tune from an 07 Redline. Only change was to the rev limiter.

PE Fuel Multiplier vs RPM Table

Starts at 13.3 afr and dives to 10.8 at 5250rpms.


This is a log of a 3rd gear run.

Things looking good at 4785 rpms.


At 5095 rpms, the AFR is rich and the IDC is 99%.


At 5752 rpms, the AFR has leaned out because of the injectors being maxed and the tune starts to pull boost.


At 6444 rpms, the AFR has leaned out to 12.4 and IDC is 147%. Tune is still pulling boost.


By 6699 rpms, boost is limited to 70%...


There are some major differences between my car and a "stock" car. I have a free flowing exhaust, free flowing intake and all the cooling mods. Plus it was like 40 degrees outside so I am cramming a lot of air into that engine.

But I think it is pretty safe to say that the stock injectors are maxed out on the stock pulley on a stock car.

I was very surprised to see how soon in the RPM range the injectors got maxed. With a custom tune, I could see that happening closer to 6000 rpms with a leaner AFR.

Thoughts?

[Papa C 2000]

I understand the need for larger injectors ( I have picked up a set of 42# Bosch green tops and am just checking to see if the connector is the only issue to resolve). I wasn't looking to fix the dip necessarily, I just started the thread to see if this MAP data I was logging was typical for a stock car. Incidentally, in my logs, it would seem that the injector duty cycle is being reported incorrectly...at least half what makes sense. I logged another 3rd gear WOT this AM from about 3500 to 6300 and the max reported DC is 52 (so 104% for real? Seeing 20-21ms pulsewidth) is there something I am missing in the scanner setup? I have logged more than 25 GM vehicles and never seen inj DC reported incorrectly. Ideas? Very strange. Sorry for getting off topic, but I see your point....the log pics you show have a MAP of 182kPa or so til the dip, 175 after. I guess mine are higher because of the restrictions of stock components (189 steady, 192 for brief periods... have seen 196kPa)

[GMRedline]

Originally Posted by Papa C 2000

I understand the need for larger injectors ( I have picked up a set of 42# Bosch green tops and am just checking to see if the connector is the only issue to resolve).

Do they look like this?



LSJ injector visual refference guide

[Papa C 2000]

Nope. A friend gave me ones with the old Bosch connectors. They are stock from the SVT Lightning. They aren't in the car now.... The stock ones are still in place and relevant to all data discussed. The ones in the car look like the pic you just posted...stockers. They just both coincidentally are lime green LOL. On a side note, my PE table isn't like the 07 you posted up. Kinda jagged, but at the higher RPMs its 1.29x. Or 11.3ish.

[Papa C 2000]

I think inadvertently I failed to remove Bank 2 inj pulsewidth PID from the default list of parameters. Maybe since this sits at zero and the other theoretically hits above 100% this is an average of the two, so 104% in my case showed 52%. Probably....makes sense. I'll hafta fix that.

[armcclure]

Correct you are