Eliminating Smoke

dangerous06

dangerous06

diesel tech
Joined
Mar 24, 2008
Messages
3,564
Ive been fighting this issue for months
changed duration = bad milage
Changed Pressure = Power down
Timing = up and down the ladder not much change Calc sheet has brought it down to reasonable levels but a thousand mile tow will black out the side of a trailer! = Unhappy Customers!!
I'm thinking hard parts need to be changed such as a smaller turbo and or smaller injectors. Would love some direction on this issue!
 
Im assuming the smoke problems are either low-rpm city driving, or heavy load lack of air?
For heavy load lack of air you might want to look into towing twins. Not sure if theres any kits that use the VGT turbos, never looked into it. Fleece?
For off-idle smoke theres not much you can do without killing power. Raising compression a little can help. running injectors with more holes and lower timing can help (but may lose top end power with higher boost). Injectors with micro-blind nozzles drip less fuel and dont wear unevenly like VCO's can. Sometimes messing with the cone angle along with timing can help too.
Aftermarket cams and head porting will hurt low-end airflow which generates the swirl needed for good combustion. Having the wrong converter stall can hurt economy and make smoke too. 1800rpm or so is the efficiency sweet spot I think.

Also, if you have money to burn there is a gentleman who offers a kit to mount a whipple supercharger over a larger single or twins. That would take care of your low end issues, especially with an aftermarket cam or head porting.

Hope that helps, been banging my head against the wall with my 12mpg for awhile.
 
I have been fighting the same issue with oppacity. Not really to concerned with Mileage as the truck is not a daily drivier but I would like to have a truck that performs and be as clean as possible. I am running an HX40/HT3B set up with DDP 90hp injectors, a Colt stg 2 cam and 33% over 6.7L CP3. Using UDC we have been able to tune a lot of smoke out and be in the mid 600 hp. At load it has just a haze but in the bottom it is pretty bad. Even worse when cold. We have installed BBI injectors in a couple trucks and they appear to be much cleaner. I am inclined to think that an injector change for me would be the next step. I was surprised that UDc doesn't quite give the ability to tune the low end smoke out as well as I had hoped although it is much better than it ever was with SSR or the S06.
 
low end smoke is a problem because theres not a whole lot of air to be had. These heads are made with swirl ramps and restrictive ports to promote swirl but theres a trade-off with top end power.
Higher compression or higher RPM would help, especially with the cam. Only way to generate boost off idle would be a supercharger. Thats the direction I want to go in, just dont have the cash =p
 
kawi600 said:
low end smoke is a problem because theres not a whole lot of air to be had. These heads are made with swirl ramps and restrictive ports to promote swirl but theres a trade-off with top end power.
Higher compression or higher RPM would help, especially with the cam. Only way to generate boost off idle would be a supercharger. Thats the direction I want to go in, just dont have the cash =p
Click to expand...

That is one reason I didn't put twins on my Rat Rod. I am holding out to go with a supercharger. I agree with you completely about the off idle boost pressure. Also about nt having the cash at the moment.:hehe:

I also believe that what you are suggesting is curing a symptom of poor tuning ability.

I think it is possible to tune the smoke out of a common rail, I just think the tuning options are not there yet for the SCI trucks. I find it difficult to control the off idle duration with UDC. I think you need to have the ability to reference the boost MAPs to get it to clear up more.

Rail pressure helps but I think it can only do so much.

Just to be clear, i am not complaining about UDC. To date it is the best program i have used to tune my truck and covers most of my needs. It would be nice to get a little cleaner but for the most part I have no issues with it as it is.
 
It is that turbo you run. I have BBI 1's, a 64/68/.9, twin pumps, and 181 210 cam and towed an 11k+ pound trailer all over the mountains on the same tune I ran a 12.8 on and their wasn't a hint of soot on the trailer and only very slight soot around the exhaust tip. Unloaded is pretty much smoke free just normal driving and I tuned it myself with some pointers from Les at silver bullet tuning. I think you should down size your turbo to a 63/68 and see what it does. The compressor will flow close to the 64 if not as much and it will light much sooner and easier.
 
If your running T3 housing then my guess your smoke issues are not program related.. I have seen 2 or old exhaust housing on turbos cracked.. If not that then you have tq table or to much timing.. This is not a UDC issue..
 
cj42 said:
If your running T3 housing then my guess your smoke issues are not program related.. I have seen 2 or old exhaust housing on turbos cracked.. If not that then you have tq table or to much timing.. This is not a UDC issue..
Click to expand...

I think he runs a 74mm exducer turbine.

Wasn't implying that its UDC's fault. The lack of boost limited fueling capabilities with UDC must make a laggy turbo difficult to tune was my thought hence the UDC tuner comment.

Like tuning a 12v without an afc foot ha.
 
joeshtrddsl,

Would you share your UDC program? Would be nice to take a look and see what may be working for you and compare settings?

I am fairly happy with how mine is working with stock over a S478. This weekend I am going to put a Silver 62 I used to run as a single to try and see how I can get it to spool. when I used this as a single I was able to drive around the lower rpm range to avoid smoke. I think having the new injectors and UDC I am hoping to get this to be a usable setup. I understand this turbo will spool slower than it did as a single so just hoping UDC and other hard parts I have installed now will help with the adjustment.

I have the turbo sitting on a shelf so why not try and see if I can make it work.

This turbo has the same exducer as dangerous06 but just a 62 not the 64.
Will not hurt to try it. I think?
 
UDC has a long ways to go. Until we get RPM based torque limiters or requests and smoke limiters, there isn't a lot we can do without compromise.
 
A small leak at the turbo to manifold found loose bolts AGAIN! Anybody have a cure for the hard to tighten and loosening up mounting bolts? This would cause the smoke somewhat.
 
There is no reason why you can't clean up smoke during normal driving with UDC. The tq table and timing table can clean up a majority of smoke. I have heard that the t4 turbo housing get cracks which can cause smoke down low. Don't know if you have that housing but I have heard of 3 in that past yr. If your trying to use smarty sample tq table with a slow spooling turbo then that will cause smoke. If you drop duration and do not do timing in the same area you so get smoke. If you can put your stock program in and have no smoke down low or cruising then it's a program issue probably. If you get smoke running stock then you might have a turbo issue. Then you want to see if you can hold boost while cruising..Also remember you really shouldn't have to mess with duration below 3000 rpm on the table..
 
The last tune I saw of yours, posted here on CompD, the issue is your timing map/split doesn't match your Silver 64, to much timing to keep it spooled in the mid range.
 
I have battled the same thing you have and won. LOL What exhaust manifold are you running? A cam upgrade to a Hamilton 178/208 will also be in your best interests. These are 2 hard parts you will need to look hard at. I don't have UDC either, well, Yet.... Working on that.
 
any thoughts on getting converter loosened up, so you can spin the motor faster, get a little more spool before you start getting into load? or you could try the od switch, helps make the truck down shift to generate rpm, and thus, spool.
 
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