I have a JLT II and Dougs race tune installed along with ford stingers. I have noticed alot of black (I guess carbon) on the chome tips anyone else have this problem and is it something to be concerned about.

I did not notice this until after the stingers were installed.

Thanks for the any input I can get.

Chris

By the way dougs tune and JLT CAI along with the stingers are amazzzzzing people love them.:banana:

 

Could be running rich? What is your A/F Ratio?

 

I have the same issue...the black carbon....I never knew what it was..

I have a C&L Racer intake and Dougs 92 Race Tune, before that however I was running a local custom tune...I suppose I could have been running rich.

Can you find your A/F Ratio on the Diablo Tuner?

 

i guess your'e almost certainly running just a bit rich, as opposed to running dangerously too rich which in turn would cause further symptoms (backfires, and a strong smell of unburnt fuel vapors)

checking the A/F Ratio isn't possible with a Predator or SCT XCal unless you have an A/F sensor installed, only then you can pick up the PID and read it.

your best bet is to take it to a dyno tuner and have them check it

 

It's because you are using 93 octane gasoline or 91+ octane gasoline. The race tunes may have higher spark values, but it isn't enough to burn it all off cleanly due to the higher anti-knock quality of 91+ octane fuel.

I run 87 octane and the exhaust pipes are extremely clean.

 

Figured as much about the dyno thing to check the a/F ratio

Is there a way to clean the carbon off the exhaust?

 

I had the carbon on my exhaust after installing my SLPs... now I still have carbon buildup on them after installing the C&L intake and dougs tune... originally upon crank up before the tune my car would pop and crackle some after a little acceleration on a cold start up which leads me to it might have been running rich... but now that I have dougs tune and the intake my car no longer does it.

 

I noticed that too, I just figured it was just normal

 

I have it too. No problems whatsoever. Like me, you may notice around where you live that other cars that have chrome tips but clearly no custom tune also have carbon build-up.

Jon

 

I have it to, and it wont come off no matter how hard i scrub, it no big deal though.

 

You'll get this even with your a/f right on the money. It has more to do with the car's parameters upon start up- I think.

 

No, it's not the AFR on the dyno nor is it some other parameter. It is from running 91+ octane gas. Not all of the gas is burned up so you end up with a lot of carbon soot that eventually clogs up your cats (if you still have them). The tunes will not solve this problem because the extra spark is still not enough to burn 93 octane as cleanly as 87 octane.

 

Well that makes sense, except for when I ran the car stock on 87 octane, I still had the carbon on the tips. Metroplex- I know you say yours is clean; do you still have the factory tips or do you have a rolled tip where it would seem to be more noticeable due to the design?

 

The rolled tips catch more of the exhaust. When I had my Stingers I had the same problem. Now that I have the GTA muffers there isn't any carbon. It is a pita to remove but use some brake cleaner and it will come off.

 

Yeah, that's what I was wondering..... for the first couple months of owning this car, I ran 87 octane with the factory exhaust; didn't notice any carbon. Then I added Bassani mufflers with the rolled tips; all of a sudden I started getting the carbon noticeably, all the while running 87 octane. I remember when I went for my first dyno tune at Brenspeed, I asked Brent about it and he stated it was pretty much normal on these cars, he had seen it on every Mustang they had worked on.

Maybe running the higher octane enhances this problem, but I think that for the most part all 4.6L Mustangs with the Spanish Oak computer have this residue.

 

I have the stock tips on the GT, but on all the other cars that I've run 87 octane on since the start have clean exhaust interiors and tips.

The PCM will try to keep the AFR at 14.6-14.7:1 in closed loop regardless of what octane you're using, but 93/94 octane will generally carbon up the exhaust much faster (within 1-2 years). Running in open loop longer than necessary or more often will also accelerate this process (open loop using any gas results in a commanded AFR of about 12.2-12.5:1).

 

I had the same build up. It will come off with Mothers Chrome Polish or Eagle 1. Takes a good bit of scrubbing but it will come completely off...look better than new too! If I dont let my car warm up before driving off i've noticed it pops a lot too..and the unburnt fuel smell stays in my clothes...its great!

 

Well I'm running a 91 Brenspeed tune and I'm happy to report "no issues".

 

Ive run nothing but 93 since the beginning and with a "canned" superchips tune, the inside of the tips are just as clean as the outside. Another forum member can vouch for that.

 

The 03 E-250 has run nothing but the cheapest 87 octane fuel on the stock factory tune and the insides are clean!

The 00 Vic has run 93/94 octane with a SCT Tune (before I got the PRP) and the pipes were pitch black within 8 months. Another member was behind my car on the highway and noted black smoke coming out whenever I went WOT.

For the 07 GT, it's getting 87 octane and I'm keeping the stock tune.