68 camaro supercharged 5.3 idle problem

[danny68ss]

it ran fine i put a intercooler on it now when i rev it and let off it will surge and die it will start right back up and idle fine until i rev it again what do i need to adjust the throttle body is on the supercharger and it goes through the intercooler before it goes into the intake

[brian617]

Why do you need an intercooler for a supercharger?

[EagleMark]

Pictures?

[Buzz]

Why do you need an intercooler for a supercharger?

Increased thermal efficiency (i.e increased power output, reduced knock sensitivity, etc.) - just like the OEM LSA and LS9 engines - factory superchargers, with factory intercoolers.

[brian617]

I understand what an intercooler does and why you'd need one with a turbo as the turbo heat soaks the intake charge. Cooling cold air seems futile to me lol.

[Buzz]

I understand what an intercooler does and why you'd need one with a turbo as the turbo heat soaks the intake charge. Cooling cold air seems futile to me lol.

That is just it - the air stream coming out of a supercharger is not as cool as the air going into it. Ever notice how the 80 gallon tank on the compressor in your shop can get very hot to the touch when using multiple air tools ? It is not soaking up any heat from anything - mechanically compressing air causes its temperature to increase.

[danny68ss]

it was running 230 degrees before now about 120 but it just wants to die out when i let off it fast

[Buzz]

My apologies for the thermodynamic sidetrack ....

That is a good reduction in temperature. Where are the MAF and IAT located in the air stream ? Also, you never posted a tune ... what are you running the the 5.3L with ? PCM, E38, E67 ?

[danny68ss]

no maf the iat is after the cooler right before the intake

[EagleMark]

it was running 230 degrees before now about 120 but it just wants to die out when i let off it fastI had no idea SC made that much heat! Almost 50% reduction in IAT is huge!

I know the tune is more important and your lucky to have Buzz helping, but if you have a picture I'd like to see the setup...

[Buzz]

I took a very quick look at your tune. You are running an EFILive COS3 OS. Do you have a WBO ? How have you been tuning thus far ? It appears as if the Boost VE table has not been refined beyond the initial setup.

Can you post a log of the stall event ?

You may get more hands-on support with this if you were to post on the EFILive forum.

[brian617]

Compression = friction = heat I get that, but 110* reduction in IAT I had no idea it could be that much.

[danny68ss]

no wide band i need to get one bad lextech helped me and set up a starter tune it runs good now but i know it needs a lot more tuning it wouldnt run over 5000 until i changed injectors and put the intercooler on it here is the log of it ideling

[danny68ss]

I had no idea SC made that much heat! Almost 50% reduction in IAT is huge!

I know the tune is more important and your lucky to have Buzz helping, but if you have a picture I'd like to see the setup... here are a couple pictures

[lionelhutz]

That is quite the project. Did that start out as a manifold mounted supercharger?

At any rate, why is the throttle body before the supercharger? All the air volume between the throttle body and the engine will really mess with your throttle response.

[EagleMark]

Sexy!

Before the cooler did the air run right in front of the radiator? Just wondering how much of that temp drop was compressed air and how much radiator heat?

[danny68ss]

It came out of the side toward the intake went straight into the intake

[danny68ss]

It's a whipple sidemount it was not designed to have a intercooler it was a short distance between the throttle body and the intake before I tried to put the tb back on the intake but the supercharger makes a very loud farting sound when I did I have the same setup on my silverado ss I had it tuned and it runs fine but he won't tell me what he changed

[Buzz]

OK … as a preamble, my posts tend to be to the point, but no negative connotation is intended nor implied.

At the outset of this project I recall two things in particular. One, that you had a similar setup in another vehicle that operated well, but that you had purchased this tune. Two, I recall a “spirited” discussion regarding tuning options - MAF only, SD only, and blended MAF & SD (OEM style).

Fast forward to the present … your induction configuration does not include a MAF sensor, which effectively eliminates 2 of the 3 tuning options. This is not a problem for an experienced tuner, but is not an optimal situation for a novice tuner. A novice tuner may find a MAF only tune as the most simple way to begin the tuning process. As experience is gained, working with the VE table(s) becomes less intimidating. Eventually, this may lead to migrating to a blended tune (MAF & SD), or even to a pure SD tune.

The tune you posted is an open loop (OL) SD tune - which means there is no fuel trim afforded by the PCM via the narrow band oxygen sensors (NBO). Again, while not a problem if the VE table and / or MAF table are highly accurate, it is generally not the most forgiving configuration for a street driven vehicle. Properly used, the short term fuel trims (STFT) can be very beneficial.

The above process requires the use of a wideband oxygen sensor (WBO). I would not run this engine at all without a WBO connected. The posted tune with respect to airflow, is virtually stock, and is not representative of the engine’s new forced induction airflow dynamics.

The question you need to ask yourself is, can you reasonably learn how to tune a forced induction engine, within the time frame allotted for this project. With an open ended time frame, a WBO, and a great deal of self-education, I have no doubt that you could do it. Sometimes a quality dyno tune is money well spent. Just something to think about …….

When you finally obtain a WBO, I foresee future questions regarding how to connect it to your V2, and how to configure the PIDs.

There was a gentleman on the EFILive forum that would walk people through their tuning projects from beginning to end. Sadly, he passed away.

I have neither the time, nor the inclination, to provide support at that level. I try to answer questions, point people in the right direction, and assist with their decision making processes.

If you decide to try and tune this project on your own, I would recommend not running the engine further until you have a WBO connected.

[danny68ss]

its going to be a track car it runs great plugs look good no detonation it just wants to die if i let off it fast i know im in over my head tuning it but i hate to just give up because something is difficult i appreciate the help.

[Buzz]

In no way was I telling you to give up - just encouraging you to think logically. If you are up to taking this on - awesome. Get yourself a WBO, and starting reading the AutoVE Tutorial that came with your EFILive software.

As far as how it is running - after you have a WBO providing a readout you may rethink this statement. From the O2 mv in the log you posted, it is running rich - which is much better than lean.

While you wait for the WBO to arrive, don't run the engine under load. As far as the stalling goes - it could be a lot of things, or the interaction of several things. You could try adding some air to the B4307 table. Also, you could increase the target idle speeds in the B4603 table. Once you get the tune squared away a little, the Throttle Follower / Throttle Cracker tables may need some work to polish how the engine returns to idle, or how it coasts down to a stop.

I am time starved these days, and other than a few minutes here and there, I don't have much time for forums - but, I enjoy participating when I can.