Reducing Smoke?

[JTaylor2005]

Hi All!

I spent the whole of yesterday giving my 306 HDi a really good clean up and I am really happy with the results. The one thign I'm still not so happy with is the spoke it produces. It's currently on a Stage 1+ map and when you give it some abuse it smokes quite a bit.

I am wondering whether anyone has any ideas how to lower it? Idea's I have come up with so far.

- Go back down to a lower performance map. (Perhaps somewhere around the 115hp mark with a lower fueling level at lower RPM's (Before turbo has spooled).
- Fit an intercooler to allow colder, more dense air in to better use the diesel going in?
- Some kind of good quality fuel additive??
- Have the injectors refurbished with new nozzles to make sure the fuel is atomizing properly? (Is there anywhere that still does this?)

Any ideas would be much appreciated!

Cheers.

[Toms306]

The S1+ is a bit smoky as standard. You could drop to a stage 1 which should be about 125bhp.

Adding an intercooler would help, but not worth the hassle and reduced reliability (more chance of boost leaks) unless you're going S2 power. Fuel additive won't make any difference.

I doubt any diesel specialists are still open during lockdown, but there are still some about. They're spread fairly thin so it's generally a postal service now. Again, I doubt it'll make any difference though, the plus map is designed to push the limits.

Have you still got the standard exhaust btw? Decat makes them smoke more, the hot cat helps complete the burn normally.

[JTaylor2005]

Ahhh. Most people have been telling me a Stage 1+ should have no smoke :S I might see what I can get map wise and perhaps drop down one step.

The exhaust is now a standard one. I have given the car to my mom to run about in so I had to take the big exhaust off. I think it might be a bit restrictive for this map but the lad from HDi Tuning said it should be OK as to be honest my mom will never drive it to the limit anyway.

[madmadmax]

improve air density on the intake side and reduce egts . so the most oveous way is an intercooler but its going to have to be testing to fined out a combo that will work

[Ruan]

If it's smoking when the turbo is spooling and there's no air leaks, it can be calibrated out, response will be moderately affected, but shouldn't be too much. If it's smoking once the engine is up to max power, possibly some changes to SOI and fuel pressure modifications will help to drop the smoke levels if your pump is capable of supporting it.