Modded EVO X's, normal to smoke under WOT?
 

My setup:

AMS boltons, FP Red, 1000cc, 255 intank, etc. etc.

Tuned on pump to 25psi at 11.2:1 AFR. Under WOT, I get a good amount of black smoke. Are others in this forum experiencing the same thing at that approximate AFR?

- Louis

I've got the WOT smokescreen mod too ;)

Fireballs even yesterday at the autocross (and I thought we'd gotten rid of those, but oh well). The fireballs were during shifts though.

Cool... I am going to assume it's normal. What made me question it was that at "Stage 2" with boltons, stock turbo, and COBB AP flash, I was in the low 11's AFR, but without the smoke.

I'm sure it has to do with the fueling changes I made by installing the 255 intank, 1000cc injectors, etc.

Hmm... well, you're tune is with your current setup right? Do you have a wideband installed on the car? It might just be that your car is running richer on the actual street.

Also, how much smoke are you seeing? I think it's expected to see a LITTLE bit, but not a smoke screen worth.

Does it go away at idle?

Agreed...you should really not be producing too much smoke with even a conservative AFR...is the smoke constant through the WOT range or is it only on spool up?...(transitional)....some transitional richness is tolerable...but it should clean out through the powerband....

-Jack

It never smokes at idle, or partial throttle driving. It's mostly during the transition, and does taper off toward redline.

I don't have a wideband in the car, but I will be putting one in soon. We used a sniffer to tune to 11.3 - 11.1 on the dyno... so I am sure that it has to be a bit richer up at the front of the exhaust system.

I've got a wideband and my AFRs are fine at WOT (think 11.5ish).

The "smoke screen" comment was mine because of how bad the stock tune was. You could write in the soot on my rear bumper after a track day. Now on this tune, I get puffs of smoke and fire, but not enough to make the rear of my car dirtier than the rest of the car.

Wishes my trunk was EVER the same color as the rest of my car...FIREBALL MOD FTW! If you're seeing 11.2 at WOT then you should still be seeing a fair amount of smoke at WOT but not a ton. Even when I was running 11.4~ I was still seeing a good amount.

I have a Cobb AP stage 2 with HKS map, and a Ultimate Racing turbo back with a test pipe instead of a cat. It puts out a slight amount of black smoke during wot acceleration, but not very much. I have also seen others do it as well. Removing the cat is going to increase the smoke out put a bit.

Yeah, I have no cat as well. I'm curious to get a wideband toward the front of the exhaust, maybe in the downpipe, to compare readings there vs. the sniffer on the dyno.

I have stage2 cobb, perrin tbe, aem intake, and I only get smoke when the car is cold.

Black smoke is excess fuel.

White smoke is blown piston rings (white being from oil)

As your building boost (since you have 1000cc injectors and a 255lph whineboro) your toon is most likely really rich in the lower RPMS, and is probably really conservative... but as you get closer to red line, you will likely notice less black smoke due to leaning the car out.

If I can remember correctly... the sniffer on the Dyno if suppose to be calibrated to be right on with a wide band that you would place in the down pipe section. + or minus a few tenths.

-Chris

And blue is a blown head gasket... radiator fluid. I think..

Um, I think you guys have it a little bit twisted up...

Black is excess fuel, correct.

White is usually water vapor, which comes from a blown headgasket, cracked head, etc... any situation where coolant/water is able to enter the combustion chamber.

Blue is oil. Burning oil can come from bad rings, bad valveseals, bad valveguides, pressurized crankcase, etc.

- Louis