Boost Spike - Page 6 - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

ayousef · 06-26-2013, 08:50 AM

Detonation will occur in the compression stroke, so both intake and exhaust valves will be closed at this time?

Also the actual throttle % is still dropping a little vs commanded TPS % bit right when it starts boosting.

why is your injector duty cycle 24% at this load range, what injectors are those and do you have the correct data for them? I cant remember checking this or not.

Your TPiS looks like its been sent from Mars? lol

PMJ · 06-27-2013, 12:20 AM

Quote:

Originally Posted by ayousef

Detonation will occur in the compression stroke, so both intake and exhaust valves will be closed at this time?

Also the actual throttle % is still dropping a little vs commanded TPS % bit right when it starts boosting.

why is your injector duty cycle 24% at this load range, what injectors are those and do you have the correct data for them? I cant remember checking this or not.

Your TPiS looks like its been sent from Mars? lol

So you are blowing my theory

. I see the gap in Throttle and Desired Throttle...that is odd especially since I was easing into it...did not floor it. However, why else would it boost spike at that point? I was making boost...the bypass was closed, and all of a sudden I go lean, detonate and boost spike... Looking back at my logs, every boost spike was during detonation.

Now I remember my first theory was the boost spike was causing detonation, but I had a change of heart until you stated it wasn't an option.

Yes, my TPiS has been an adventure...I'm hoping the saying is accurate that good things come to those who wait... I'll be upset if I get a dud.

PMJ · 06-27-2013, 10:35 PM

It showed up! Now I have to pull Bill away from his build project to tune for my new TB...

JANNETTYRACING · 06-28-2013, 07:03 AM

Quote:

Originally Posted by PMJ

So you are blowing my theory

. I see the gap in Throttle and Desired Throttle...that is odd especially since I was easing into it...did not floor it. However, why else would it boost spike at that point? I was making boost...the bypass was closed, and all of a sudden I go lean, detonate and boost spike... Looking back at my logs, every boost spike was during detonation.

Now I remember my first theory was the boost spike was causing detonation, but I had a change of heart until you stated it wasn't an option.

Yes, my TPiS has been an adventure...I'm hoping the saying is accurate that good things come to those who wait... I'll be upset if I get a dud.

Detonation will cause Air flow to Stall in the Manifold which feeds back to the MAF and shows up as Less Flow during detonation, less injectors Milliseconds and more timing in some cases.

Ted.

PMJ · 06-28-2013, 07:40 AM

Quote:

Originally Posted by JANNETTYRACING

Detonation will cause Air flow to Stall in the Manifold which feeds back to the MAF and shows up as Less Flow during detonation, less injectors Milliseconds and more timing in some cases.

Ted.

So does that mean my theory may make sense? About the detonation causing the boost spike?

Thanks,
Pat

JANNETTYRACING · 06-28-2013, 08:57 AM

Quote:

Originally Posted by PMJ

So does that mean my theory may make sense? About the detonation causing the boost spike?

Thanks,
Pat

ABSOLUTELY

PMJ · 06-29-2013, 06:54 PM

Installed the TPiS...I have some tune opportunities all the way around. Was able to reproduce the boost spike by getting off and stabbing the throttle with slim to no throttle delay. BTW, I was not logging AFR on this log, I certainly had a lean spike when I got back into it...

Too bad Ted's not in Houston ...

Mike TexaSS · 07-02-2013, 01:41 PM

Tune it SD!

Mike TexaSS · 07-02-2013, 01:42 PM

PMJ · 07-02-2013, 02:51 PM

Quote:

Originally Posted by Mike TexaSS

Tune it SD!

That is on the list, but next step is a Sunday tuning appt. w/Patrick G...

PMJ · 07-07-2013, 11:25 PM

No update...as I was starting my car to head to Victoria to meet Patrick (2 1/2 hr trip), my water pump pulley fell on to the ground.

This was my 3rd attempt to install that damn 10 rib pulley on my 2nd water pump...this one held up for a couple months...I thought it was a good fix...until I heard my pulley bounce on the ground.

I've been driving like this for months...how lucky am I that when the shaft decided to break, that I would be in my garage! As disappointed as I was about missing my tune appt., I was very happy this happened in my garage!

Anyway...boost spike is temporarily on hold. Meziere Electric Water Pump on the way (no pulley swap required

). Hope to be back on the road in less than a week...

PMJ · 08-27-2013, 09:51 PM

So I finally have my tune to the point I'm not seeing any KR when I stab it!

, BUT I'm not thrilled with the work around.

After numerous car issues (damn water pump 10-rib pulley

), I finally made it to Pat G's in Victory, TX to tune (specifically the VE coefficients). Unfortunately during tuning, my water pump pulley fell off

. We were able to get through the dyno tune with some bailing wire and duct tape (thanks to Pat G and Kurt's help and patients), but did not get to road test it.

(BTW, anyone putting a 10 rib pulley kit in, buy the ligenfelter water pump with the 10 rib pulley already on...trust me, its worth it! - I only wish I knew about it 4 water pumps ago...)

After I got past my water pump woes, I final tested it hard...the lean tip is pretty much gone, but the boost spike was still there resulting in KR (see first pic). So now I'm back to my original theory that the boost spike is resulting in KR (vs. the KR causing the boost spike).

So I decided for now to "govern" the throttle opening rate (Airflow -> ETC -> Area Rate Limits Opening Rate). To prevent the KR, I had to drop 3rd and 4th gear down from 100% to 2% for the "Throttle Area Increase Rate". I was concerned with the impact, but if you see the 2nd pic, it gets back to 80% throttle almost immediately and then gets back to WOT about .1s later... I think this penalty will be much less of an impact than the 10* of KR

...if I ever make it back to the track, I hope to find out.

dookie454 · 09-19-2013, 11:34 AM

Hey PMJ... were you over at HPTuners asking about this? If so I'm the one (10_SS) that mentioned reducing the opening rate... So far so good? It's a must I believe.

I was wanting to find someone with this same blower as myself to see if you notice a spike from around 95-110kpa? This would be when the bypass valve closes I assume... so imagine part throttling it then it gets to about 95kpa then suddenly bumps to 115kpa as the bypass closes I assume... this is kinda annoying since there is no way to smoothly transition...

It actually causes a problem on a road course going around corners when your on the cusp of slide...

If you dont see it them maybe I need an adjustment or something.

my LT1 Procharger never did this... silky smooth transition.

PMJ · 09-19-2013, 09:18 PM

Quote:

Originally Posted by dookie454

Hey PMJ... were you over at HPTuners asking about this? If so I'm the one (10_SS) that mentioned reducing the opening rate... So far so good? It's a must I believe.

I was wanting to find someone with this same blower as myself to see if you notice a spike from around 95-110kpa? This would be when the bypass valve closes I assume... so imagine part throttling it then it gets to about 95kpa then suddenly bumps to 115kpa as the bypass closes I assume... this is kinda annoying since there is no way to smoothly transition...

It actually causes a problem on a road course going around corners when your on the cusp of slide...

If you dont see it them maybe I need an adjustment or something.

my LT1 Procharger never did this... silky smooth transition.

Yes, same PMJ. I finally made it back to the track last weekend. I finally got my 10s run, but the slower throttle actually hurt more than it helped (I should have look closer at my logs while I was there).

The above log shows a nice gradual transition to WOT...this was on the street and I thought it was a good fix. As you can see in my first run at the track below, the slower throttle turned into a mess... I guess I was shifting too fast

. You can see I shift, floor it, the TPS opens rapidly to 50%+, then starts to close back down to 30%, and then flies open about as rapidly as I floored it originally and results in the exact same boost spike and lean spike...just took longer to get there.

I'm as confused as ever, but when I get this issue solved, I can take another .5s off my time!

I'm headed back to Victoria to see Pat G again. This time we are going with a SD tune in hopes of removing the lean spike.

-Pat

06-26-2013, 08:50 AM	#71
ayousef Drives: 2013 ZL1 Join Date: Oct 2012 Location: Dubai Posts: 757	Detonation will occur in the compression stroke, so both intake and exhaust valves will be closed at this time? Also the actual throttle % is still dropping a little vs commanded TPS % bit right when it starts boosting. why is your injector duty cycle 24% at this load range, what injectors are those and do you have the correct data for them? I cant remember checking this or not. Your TPiS looks like its been sent from Mars? lol __________________ 1150bhp Whipple 4.0 Supercharged 427ci Camaro ZL1

06-27-2013, 10:35 PM	#73
PMJ Seeking 9s on M6... Drives: 2012 2SS/RS LS3 aka "BlackWidow" Join Date: May 2012 Location: Houston, TX Posts: 397	It showed up! Now I have to pull Bill away from his build project to tune for my new TB... Attached Images __________________ [SIGPIC][/SIGPIC]

06-29-2013, 06:54 PM	#77
PMJ Seeking 9s on M6... Drives: 2012 2SS/RS LS3 aka "BlackWidow" Join Date: May 2012 Location: Houston, TX Posts: 397	Installed the TPiS...I have some tune opportunities all the way around. Was able to reproduce the boost spike by getting off and stabbing the throttle with slim to no throttle delay. BTW, I was not logging AFR on this log, I certainly had a lean spike when I got back into it... Too bad Ted's not in Houston ... Attached Images __________________ [SIGPIC][/SIGPIC]

07-07-2013, 11:25 PM	#81
PMJ Seeking 9s on M6... Drives: 2012 2SS/RS LS3 aka "BlackWidow" Join Date: May 2012 Location: Houston, TX Posts: 397	No update...as I was starting my car to head to Victoria to meet Patrick (2 1/2 hr trip), my water pump pulley fell on to the ground. This was my 3rd attempt to install that damn 10 rib pulley on my 2nd water pump...this one held up for a couple months...I thought it was a good fix...until I heard my pulley bounce on the ground. I've been driving like this for months...how lucky am I that when the shaft decided to break, that I would be in my garage! As disappointed as I was about missing my tune appt., I was very happy this happened in my garage! Anyway...boost spike is temporarily on hold. Meziere Electric Water Pump on the way (no pulley swap required ). Hope to be back on the road in less than a week... __________________ [SIGPIC][/SIGPIC]

08-27-2013, 09:51 PM	#82
PMJ Seeking 9s on M6... Drives: 2012 2SS/RS LS3 aka "BlackWidow" Join Date: May 2012 Location: Houston, TX Posts: 397	Found a work around So I finally have my tune to the point I'm not seeing any KR when I stab it! , BUT I'm not thrilled with the work around. After numerous car issues (damn water pump 10-rib pulley), I finally made it to Pat G's in Victory, TX to tune (specifically the VE coefficients). Unfortunately during tuning, my water pump pulley fell off. We were able to get through the dyno tune with some bailing wire and duct tape (thanks to Pat G and Kurt's help and patients), but did not get to road test it. (BTW, anyone putting a 10 rib pulley kit in, buy the ligenfelter water pump with the 10 rib pulley already on...trust me, its worth it! - I only wish I knew about it 4 water pumps ago...) After I got past my water pump woes, I final tested it hard...the lean tip is pretty much gone, but the boost spike was still there resulting in KR (see first pic). So now I'm back to my original theory that the boost spike is resulting in KR (vs. the KR causing the boost spike). So I decided for now to "govern" the throttle opening rate (Airflow -> ETC -> Area Rate Limits Opening Rate). To prevent the KR, I had to drop 3rd and 4th gear down from 100% to 2% for the "Throttle Area Increase Rate". I was concerned with the impact, but if you see the 2nd pic, it gets back to 80% throttle almost immediately and then gets back to WOT about .1s later... I think this penalty will be much less of an impact than the 10* of KR ...if I ever make it back to the track, I hope to find out. Attached Images __________________ [SIGPIC][/SIGPIC]

07-02-2013, 01:41 PM	#78
Mike TexaSS Drives: 454 LS7 Camaro SS Join Date: Jun 2009 Location: Houston Posts: 380	Tune it SD!

09-19-2013, 11:34 AM	#83
dookie454 Drives: 2010 Camaro 2SS LS3 Join Date: May 2012 Location: Michigan Posts: 143	Hey PMJ... were you over at HPTuners asking about this? If so I'm the one (10_SS) that mentioned reducing the opening rate... So far so good? It's a must I believe. I was wanting to find someone with this same blower as myself to see if you notice a spike from around 95-110kpa? This would be when the bypass valve closes I assume... so imagine part throttling it then it gets to about 95kpa then suddenly bumps to 115kpa as the bypass closes I assume... this is kinda annoying since there is no way to smoothly transition... It actually causes a problem on a road course going around corners when your on the cusp of slide... If you dont see it them maybe I need an adjustment or something. my LT1 Procharger never did this... silky smooth transition.