A small cornicopia of questions

[mdregister]

I have several new questions:

1. Smoke- Since my swap to the DSG timing gear set, I have noticed a marked decrease in the amount of smoke I am creating. I anticipated a decrease in smoke, but I have almost no smoke at all, is this desireable in the grand scheme of things?. With my timing set to 4.5* BTDC @1300 RPM, I get almost no smoke (black or otherwise) at full throttle and high RPM. Even kicking it down a gear and winding it out practically produces no smoke. Occaisionally, I will get a little belch of black smoke when I do this, but more often than not, I just get a whispy trail of blackish-brown smoke.

2. Nightime emmission- Even though I appear to not be emitting much smoke at all, I have noticed a trail of something at night when I accelerate. When the lights of cars behind me are at a certain angle, I appear to be trailing a cloud of vapor under load. I am guessing that the vapor is just smoke/emissions that are not visible to me from the cab under normal lighting-do you concur?. I have trailed the truck in my car and can see nothing in the daytime.

3.INTAKE NOISE-I recently purchased a Banks "wide" air intake assembly. There is definitely more air getting to the intake-BUT JESUS H. CHRIST IT IS LOUD!!!. Is that typical with that device?

[jbell]

I think the HMMMV's use a foam wrap around the paper element to lessen the non throttled diesel intake noise, as they don't have the 'acorn trap' silencer the typical NA motor has. It also acts as a pre-filter without being restrictive. Anyone know where to get those?

[TimK]

MD,

Your exhaust sounds normal to me. A little bit of black smoke under high acceleration and heavy load is normal. Too much black smoke results in higher EGT's which is hard on your pistons and results in poorer fuel mileage. The black smoke is a result of incomplete burning of fuel from too much fuel or not enough air during combustion. The amount of fuel and the timing of when the fuel is injected will affect the amount of black smoke. (Oh, a severly clogged air filter or running at high altitude will also cause a lot of black smoke by starving the engine of air.) The timing gear you are running now has placed your timing spot on. I am guessing the worn timing chain had your timing off far enough that you may have seen more black smoke before.

If the trucks feels good and runs ok, then I wouldn't mess with the timing or the IP fuel adjustment. If you like a lot of black smoke, I would suggest you get a pyrometer install so you can at least monitor you EGT's. I was talking with the guys at DSG and they tell me the 6.2L NA pistons have thin crown and are likely to crack if the EGT's get to high for a long period of time. When they did the build up for the engine I bought from them, they installed 6.5L pistons for the 6.5L Turbo model. They told me they had a thicker crown and are less prone to cracking.

The cloud of smoke that you are seeing in the headlights of other cars is also normal.

I am not familiar with the Banks air cleaner you are talking about. I do know that any naturally asperated diesel has a lot of noise coming out of the intake if it doesn't have a muffler of some type on it.

TimK