I have several questions and I know that many of you out there know the answer.


First - Can 3-4 pounds of additional boost be run safely without a chip? I have been told that the stock calibration will compensate for the additional boost.

Second - Can you always hear detonation? If you can't, does that mean that it does not exist, and is going to the dyno to get a/f numbers the only way to be certain?

Third, can the HD computer be re-flashed with the L program at the dealership? I have heard of one guy doing this, but would like to hear from an expert.

Thanks for any help.

 

2nd Q - NO, you CANNOT always hear detonation, and it CAN be there. Be careful!!

 

If you can't hear it, would the computer throw a lean code as soon as it got dangerous?

 

That sounds like a question for the Tuners, but my guess would be yes.

And to Quesion #1: I've heard that an additional TWO pounds can be run safely on a Lightning. Dunno about your HD?

 

Question 1 ) You can only run two pounds of boost over stock with out a chip, anything more ( 3 + ) will require a chip.

I hope this helps.

Larry.

 

Well I'm getting closer, Thanks!!

 

1.) Two pounds of additional boost is the safest you can go on the stock Lightning programing, but im not sure about the HD programing.

2.) You can not always here the detination. The truck has four (Some who knows for sure, chim in please) knock sensors, that will detect it long befor you can hear it. If it gets to the point where you can hear it, it's not good.

3.) It can be, but im not sure it would be benifial to the HD. You might also loose a few funtions that are unquie to the HD; if there are any.

 

Lightning engs have no functional knock sensors----none

Dan

 

Don't the new HD trucks come stock with less boost (6psi)? So shouldn't he be able to run a 4 pound Lightning pulley?

 

How can the PCM pull timeing, if there are no knock sensors when it's pinging? Sal, or any other tech?


True, but we are not certain that the stock programing for the HD can take that much more.

The best thing to do would be to talk to one of the tuners (PSP, JL, or JDM) and see what they say. They might have already had experiance with them. If not, you might have an opportunity on your hands.

 

Its true, the knock snesors are not doing a thing on our L's. And just like you said they will not retard timing if you are detonating. This is why its so important to get a custom tune or at least check it out with a wide band A/F. Outnumbered, I barrowed a wide band to run my L on the street under normal conditions and gave JL the info that I wanted my chip tuned to. If your running a 3-4 pound boost increase you need a chip and once you get it you will be happy with the power increase from the chip and pulley combo. The right program will help out your shift point, timing, torque limiters on the trans and lots more. Go for it.

 

Detonation can't be detected by a/f. You can be running fat as an opera singer, and if your timing is too far advanced, you will still get detonation. (Ask me how I know...)

In a Lightning, your best defense vs. detonation, unfortunately, is your ear. A knock sensor would probably false all day long because of how noisy the blower and engine are. It is true that the Lightning has no active knock sensor.

My recommendation is to dyno tune it, and when the truck's running up, stand by the engine and listen. If there's even a little detonation, you'll hear it with the hood up. Then just get the tuner to dial back the timing some more. There's not a ton of power difference between ragged edge and safe, so might as well run safe.

When you are running on the street, if you start to hear pinging, GET OFF OF THE THROTTLE! In a naturally aspirated car, detonation can be annoying, in a boosted car, detonation can be catastrophic.