Franchi

It's normal. I have Comp Thumpr cams, longtubes, offroad H to Bassani exhaust and smells rich. If the car hasn't been running for a week or so, super strong on fireup for first 5 mins or so, enough to where Ill back it immediately out of the garage and shut the garage door and let it warm up before taking off.

FastDEW

I have the brenspeed Detroit rocker blower cams. I'm also still on stock cats with the M90. While I get some smell, I can easily idle the car in a garage and not really have an issue. It smells a little rich, but nothing that is even near objectionable like I'm reading here.

Might be that the brenspeed cams are milder, might be that the stock cats are really good, might be that my tune is very good at idle OR it is a combination of all three of these.

Wondering now if my stock cats are working overtime to keep up...... And will they eventually melt????

GerRod

I got the smell with high flow cats. I've had a tune from just about every tuner and the car smelled the same with every tune.

jackhammer505

Well I guess i'm not alone. I get comments all the time as to how bad my car smells.
Like I said before I have owned many cars with way bigger cams and never had a smell this strong.
Must be because it is fuel injected and trying to compensate for the overlap. Carburetor idle circuits seem a little better at that than EFI.
I would love to see some other Mustangs with cams just to compare.
Probably gonna try some long tube headers along with some cats. I believe with the long tubes it will scavenge better thus cleaning out the cylinders more efficiently.
I told BAMA tunes about it and they don't really seem to care. Maybe because I have that "free tunes for life" from American Muscle.
When you have that BAMA could care less. They just email you the tunes and update when you add parts that need a new tune. When it comes to issues like drivability and richness etc. they don't really have any reason to go above and beyond.

OhEightGT

That's not entirely accurate in my experience. You may have spoke to someone that was less than helpful, or something... But I dealt with AMChrisRose here on the forums initially, then he put me in touch with Ryan McDonald at Bama. They care very much. They spent 2 days and a weekend with me on my car just a few days back, datalogging and fine tuning my car beyond the initial email tune. Then without asking at all, Ryan re-wrote ALL of my tunes to match the necessary adjustments they discovered. They will bend over backwards to help if you approach them. They went to great lengths for me, and yes, it took effort on my part as well, I had to get my laptop, datalog the car, figure out all that, but they walked me through step by step, told me everything they needed, and after all that, I came out on the other side with a spot on tune that even the dyno tuner couldn't improve on.

Try PMing AMChrisRose here about your issues. You're not going to clean up the smell with a tune, that's the nature of the beast as everyone has already stated. You probably will with the cats though. Modified car without cats, it stinks. These particular cars all do it to some degree, I can't speak for carbureated cars but on these cars, cammed, o/r, headers, etc. you're just going to smell them. Sucks for those that dislike the smell, but that's just how they are.

ffk_pennywise

Update: I had my high flow cats installed as well as some clamp leaks fixed. No more smell!

jackhammer505

OhEightGT,

Thanks for the input. I called BAMA 2 different times and spoke to 2 different people. Both times I swear I knew more about tuning than these guys. They sounded young and brand new!!!
I would ask simple questions and they would give me ridiculously stupid answers.
They just wanted to get off the phone as soon as possible.
I will try again but my experience was they didnt know and didnt care.
Somebody with more experience would be great.

Jack

jackhammer505

ffk pennywise,

Thanks for the responses. What High Flow Cats did you end up getting? What brand and are they ceramic or metallic.
I am pretty sure this will help.

Jack

OhEightGT

Yeah, you'll have to go out of your way to ask for those two. I'd pm Chris Rose here, (AMChrisRose) or call/email and ask for Ryan. I'm sure there are other great ones there, there's a reason they have the awesome reputation they do, but it sounds like you just got a couple of either new or "bad" ones. I've only dealt with those two guys so I can't speak as to anyone else there. Just like I said, when you do/if you try to talk to either of them, don't expect a tune to clean up the smell, it's simply the way these cars are without cats. But right, like everyone said if you get some cats/hi flow cats you'll be in business!

Best of luck!

Riptide

Not sure what the smell is that you guys are describing but if it is at all a sulphurous rotten egg smell you may want to try switching gasolines. High sulphur content in the fuel can cause that particular type of stench. Even with cats.