Fuel in cats?

[slickster]

Just got this car with a termi swap but no s/c yet. Just drove it and after about 30min the cats get way hot sounds like a steak cooking on the sun and smells like burnt rotors no CEL. I guess previous guy got a bad tune dumping fuel in cats I guess what else can that sound be?

[Jon01]

You mean the car you bought from me almost 6 months ago?
It has Zack's 4.10 tune with 2% WOT fuel pulled. Many, many people have run that tune without issue. Or was that tune in the x-cal you sold? If so, what did you replace it with?

[martyo]

Clogged cats.

[slickster]

You mean the car you bought from me almost 6 months ago?
It has Zack's 4.10 tune with 2% WOT fuel pulled. Many, many people have run that tune without issue. Or was that tune in the x-cal you sold? If so, what did you replace it with?

I didn't do anything to the tune I don't know why the Cats would clogged 50,000 miles

[Limited360]

Over fueling to a decel fuel cut will kill cats in no time...

Smell like sulfur (rotten eggs) from the exhaust? Does it feel like its 'loaded up' and won't really get going?

If it has no s/c but is a terminator it should be running a custom tune to account for the lower compression I would imagine, not just a straight Zack tune...

Sure he will chime in however...

[slickster]

Does it feel like its 'loaded up' and won't really get going? Yep sure does even out of park or reverse you really have to give it some gas effort to get the car moving.

[Zack]

Is it hard starting when cold?

[Jon01]

Over fueling to a decel fuel cut will kill cats in no time...

Smell like sulfur (rotten eggs) from the exhaust? Does it feel like its 'loaded up' and won't really get going?

If it has no s/c but is a terminator it should be running a custom tune to account for the lower compression I would imagine, not just a straight Zach tune...

Sure he will chime in however...

The car had 2% WOT fuel pulled, other than that it's Zack's fuel map.
It consistently got 20mpg when I owned it7, if it's still getting that I don't see it being an overfueling issue.

I've tuned cars on the side for almost 10 years now, what you're saying is false. I had a PLX wideband in the car after putting the longblock in it, it was ~ 14.4-14.8 cruising and 13.0-13.2 @ WOT. No adjustments needed.


Does it feel like its 'loaded up' and won't really get going? Yep sure does even out of park or reverse you really have to give it some gas effort to get the car moving.

You just told me via text it ran normal. Which is it?
With the stall it will take more rpm to get moving, that's how they work.
Has the car sat for the 6 months since you bought it?

[Limited360]

The car had 2% WOT fuel pulled, other than that it's Zack's fuel map.
It consistently got 20mpg when I owned it7, if it's still getting that I don't see it being an overfueling issue.

I've tuned cars on the side for almost 10 years now, what you're saying is false. I had a PLX wideband in the car after putting the longblock in it, it was ~ 14.4-14.8 cruising and 13.0-13.2 @ WOT. No adjustments needed.



You just told me via text it ran normal. Which is it?
With the stall it will take more rpm to get moving, that's how they work.
Has the car sat for the 6 months since you bought it?

Nothing I said was false. If its a straight Marauder tune it would not be running properly. I am assuming its a correct tune since its from Zack. Your feedback confirms proper AFR, proper AFR doesn't always mean correct ignition timing. Once again I have faith in Zack on this tune however.

My comment around over fueling into a DFSO, cat will break bricks if it gets hot enough... over fuel + oxygen = huge exotherm... this is known issue from selling calibrations for the North American market into other countries for OEM's... just my feedback as a possible concern IF it was over fueling, clearly you state its not.

Bad cats would be more of sign while at load on the highway or in the higher RPMs. Getting going from park or reverse is a sign of something else.

[slickster]

The car had 2% WOT fuel pulled, other than that it's Zack's fuel map.
It consistently got 20mpg when I owned it7, if it's still getting that I don't see it being an overfueling issue.

I've tuned cars on the side for almost 10 years now, what you're saying is false. I had a PLX wideband in the car after putting the longblock in it, it was ~ 14.4-14.8 cruising and 13.0-13.2 @ WOT. No adjustments needed.



You just told me via text it ran normal. Which is it?
With the stall it will take more rpm to get moving, that's how they work.
Has the car sat for the 6 months since you bought it?

Actually I said I guess I'm not used to driving a car like this. Meaning a mm with termi no sc if you ask how is your tuned stock naturally aspirated Marauder driving I could tell you. Yes it sat. The next day after it came off the truck I washed it and seeing the gravy paint

[Zack]

FYI every 'tune' ive ever made is the made with SCT's canned 93 octane Marauder file and my transmission settings.
I've never messed with MAF, fuel etc. Its not necessary.

[Jon01]

Nothing I said was false. If its a straight Marauder tune it would not be running properly. I am assuming its a correct tune since its from Zack. Your feedback confirms proper AFR, proper AFR doesn't always mean correct ignition timing. Once again I have faith in Zack on this tune however.

My comment around over fueling into a DFSO, cat will break bricks if it gets hot enough... over fuel + oxygen = huge exotherm... this is known issue from selling calibrations for the North American market into other countries for OEM's... just my feedback as a possible concern IF it was over fueling, clearly you state its not.

Bad cats would be more of sign while at load on the highway or in the higher RPMs. Getting going from park or reverse is a sign of something else.

You are correct in that overfueling will brick cats, my disagreement was that it required a custom tune.
Nothing changed besides the cams and compression between the motors. It had 15,000 miles on it since the swap when Slick bought it, a cat/fueling issue would have arisen much sooner.

[slickster]

FYI every 'tune' ive ever made is the made with SCT's canned 93 octane Marauder file and my transmission settings.
I've never messed with MAF, fuel etc. Its not necessary.

Well I recall John saying that he only had 91 up there can that be the issue

[Zack]

Well I recall John saying that he only had 91 up there can that be the issue

No because your engine has low compression

[Limited360]

You are correct in that overfueling will brick cats, my disagreement was that it required a custom tune.
Nothing changed besides the cams and compression between the motors. It had 15,000 miles on it since the swap when Slick bought it, a cat/fueling issue would have arisen much sooner.

Not true on the issue arising much sooner... sometimes its degradation overtime. A cat can live 1% of its useful life above its threshold temp for damage. That is part of its design criteria per regulations (thanks CARB).

Also different compression ratio's do affect burn rates which equate to the same AFR however with hotter exhaust temps. Cam timing / degree lift also has a dramatic impact on ignition timing (not advance). Fuel timing (not pulsewidth, start of injection timing) should also be different between compression ratio's. However this is nothing an aftermarket tuner typically changes.

Once again I do not doubt you... I think we agree its the torque converter from what it sounds like.. just not used to it.

Steak sizzling comment is interesting as gas won't sizzle in a cat... will burn!!

[Limited360]

No because your engine has low compression

+1 on this.

Plus 91 at high altitude is equivalent to 93 at low altitude if that's what you man by 'up there'

[Jon01]

Warm it up, take it out and mat it. If it runs strong it's fine. If it doesn't, you have an issue.

[Zack]

You should of just shipped this car to me for the SC install.

[slickster]

You should of just shipped this car to me for the SC install.

I know I was going to but like always I have to be an angel for everybody else while screwing things up for myself.

[slickster]

Warm it up, take it out and mat it. If it runs strong it's fine. If it doesn't, you have an issue.

And if it catches fire I'll die like Paul Walker:banana:

[martyo]

You should of just shipped this car to me for the SC install.

Heck yeah!!!!!!

[martyo]

FYI every 'tune' ive ever made is the made with SCT's canned 93 octane Marauder file and my transmission settings.
I've never messed with MAF, fuel etc. Its not necessary.

What happens when there are injectors and a meter that are not the same as a Marauder?

[Jon01]

This car has the stock Marauder meter and injectors unless he has changed something.

[martyo]

This car has the stock Marauder meter and injectors unless he has changed something.

It does and he didn't. I was asking a different question.