Dynomax Bullet Cats SUCK!

Contour Enthusiasts Group Archives

As the title states, Dynomax bullet cats suck! Not even 1000 miles and mine is FUBAR.

I started to have issues with high amounts of load w/ low RPM/MAF counts that just got worse and worse. I let it sit over night and today after work, it was REALLY bad. After letting it idle a bit, I noticed that my whole exhaust system was GLOWING

Even my muffler's innards.

Once it cooled to a non-glowing state, I dropped my cat-back and my car was back to normal.... just louder. The POS is getting a gut job tomorrow!

A good test on how well the heat wrap and other forms of heat protection worked! No wiring, hosing melted or the like. Even my radiator (the DP runs along one side of it, and within 1/2-3/4"

) was safe from what happend. My ECT didn't go over 210 the whole time.

Metal matrix cats, only way to go.

I made it easy on myself and got rid of cats all together.

Originally posted by gotapex:
Metal matrix cats, only way to go.

or no cats at all

Originally posted by Swazo:
As the title states, Dynomax bullet cats suck! Not even 1000 miles and mine is FUBAR.

I started to have issues with high amounts of load w/ low RPM/MAF counts that just got worse and worse. I let it sit over night and today after work, it was REALLY bad. After letting it idle a bit, I noticed that my whole exhaust system was GLOWING Even my muffler's innards.

Once it cooled to a non-glowing state, I dropped my cat-back and my car was back to normal.... just louder. The POS is getting a gut job tomorrow!

A good test on how well the heat wrap and other forms of heat protection worked! No wiring, hosing melted or the like. Even my radiator (the DP runs along one side of it, and within 1/2-3/4" ) was safe from what happend. My ECT didn't go over 210 the whole time.

I don't know what to tell you.. IN almost every case, glowing cats is a product of running too lean at cruise! Maybe at full throttle too. In the old days when air was added into the catalyst chamber to help complete combustion and reduce emisssions. Anyway, in too large of amounts the air would raise the temp of the catalyst and would overheat and crack it.
Too rich leaves them too cool and they clog up with soot.

So when you have glowing pipes and catalyst problems you'd better check your damned air fuel right away with a real O2 sensor like a wideband. Also, carefull you haven't already burned/damaged the O2 sensors. They may not read right after running so hot.
The factory programming has a calibrated heat range that if exceeded will cause the computer to add more fuel and richen the mixture so as to reduce combustion temps and cool down the sensors and or catalysts.
Something isn't right.

BTW
There is no reason NOT to run catalytic converters except environmental irresponsibility, or an all-out race motor that isn't driven except for track days!

I had a few issues with older o2's (70-7.5K) and bad (2-3 year old, which was flushed and replaced with 91 crapoline

) gas and a funky AFR right off the bat. Once I got the AFR within reason (According to my Innovate LM1) and really started to drive it was within the last few days, which is when I have had this growing issue go from bad to worse.

I installed brand new Denso o2's tonight and will be gutting my cat tomorrow, until I can get a better quality unit that is. With a little open exhaust runs around the neighborhood tonight, everything is within reason.... other than the loudness

really nice cats

Well good luck! I can't wait to see the numbers.

Are you tuning with your Pro Racer package and and innovate wideband?

Originally posted by beyondloadedSE:
I made it easy on myself and got rid of cats all together.

same here

cats are overrated

~Andrew

Originally posted by Lebowski316:

Originally posted by beyondloadedSE:
I made it easy on myself and got rid of cats all together.

same here

cats are overrated

~Andrew

Yeah, and your engine probably is too....

j/k, I'm not going to beat someone up over it because it is your choice. However, I think you should be responsible and use them; if you design it right you won't loose any power. BeyondloadedSE has a race setup so I can understand why he didn't go with them, but if he daily drives it then....

I don't have cats either Tom. So there pokey.

Mine was a packaging deal. It was just too much of a PITA to fit them in. These metalicats weren't available when I made my setup. If I had to do it over now I would have run 2 of those and no resonators. (and Dynomax mufflers)

Originally posted by warmonger:
Well good luck! I can't wait to see the numbers.

Are you tuning with your Pro Racer package and and innovate wideband?

Oops, didn't see this post before.

Yes, I am using the PRP and Innovate WB. I'm dicking with drivability issues now, but I am hoping to have a pre-fine tune dyno run by the end of the week

A fine tune will come in January w/ another dyno run then. Also, 103 unleaded is available around the Salt Lake area (5.25-5.50 a gallon

) and I will be doing the 'race' tune with it.

Cool. What kind of driveability issues do you have? Can I help out?

Thanks for the offer Tom, if I had more time I would have taken you up on it. I'm swamped with work, so my time is too valuable to deal with it. BUT, I want my SVT drivable NOW, and am willing to let Heath @ Modular Madness West wrap it up.

It's just some minor idle issues that need adressing (dashpot?). I'm guessing it's the way I have the IAC hooked up, but it can be fixed in the tune.

I dropped my car off yesterday and they did an initial base line dyno with the tune I've been dicking with. I'll be scanning them and posting them in the Dyno/Drag later tonight.

247.4HP @ 5850
and
261.7TQ @ 4500

The engine is seeing only 3.5psi after the IC pressure drop. Once the AFR is improved on, I should see even more power when at the lowley 3.5psi

Once it's actually broken in, I can fine tune it and crank up ze boost

Make sure you IAC isn't connected backwards -
i did that when I first reinstalled mine (similar to your setup) and had it backwards and it idled like crap. After looking at a stock intke mannifold I saw my fubar - flipeed it around and was good to go!

Originally posted by Swazo:

247.4HP @ 5850
and
261.7TQ @ 4500

Thats a good start!

I bet with a redline pull your around 270 whp or so.

That's nuts with only 3.5 psi

Originally posted by Stazi:
That's nuts with only 3.5 psi

....no doubt,cant wait to see race tune with more boost

with a dyno video too

Did I mention that these numbers are from a Mustang dyno and unadjusted?

Originally posted by Swazo:
Did I mention that these numbers are from a Mustang dyno and unadjusted?

Swazo, are you planning on coming to SZ this year?

As long as my SVT doesn't die on me, I'll be there one way or another!

BTW, this is the same dyno Fastcoug's turbo SVT basketcase put down 230HP/203TQ on.

Hey man for as long as that has taken you to put together...those numbers suck!!!

just kidding. I really wish I had time to finish mine up.

Originally posted by Stazi:
That's nuts with only 3.5 psi

The tuner told me over the phone at lunch time that it was 283TQ

I was a little let down that he had been mistaken

Wow. Sounds very impressive.
What was the compression on the engine and the turbine size again?
This is also with SVT cams right?

I posted my mod's along with the dyno sheets here

Originally posted by Swazo:
BTW, this is the same dyno Fastcoug's turbo SVT basketcase put down 230HP/203TQ on.

Seriously though, great job!

Thanks!

You know I'm speaking of your SVT BEFORE it graced the inside of your garage, of course

I must say that the car has potential ... with 6 cylinders ... that dyno tune was on 5 cylinders and would explain the low torque ... just imagine if she made decent boost (never rose above 4psi for me - never got above 5,000RPM) and on 6 cylinders no less

Since I am completely redoing the kit and the Cougar has no A/C and I want to make this tubing kit available to others, I think that I'm going to use the Contour as my "mule" test-bed for the turbo kit. After the kit has all the kinks worked out and my 3L SVT is running 300+hp/tq, then I will probably turn around and sell the car.

I haven't been following your story. What is your car's configuration?

For the psi your SVT was running on the dyno, maybe it was only running somewhere around 5psi.

Once you get your pipe routing finished, deffinatly make a jig! A low cost option for people is deffinatly needed

Originally posted by Swazo:
I posted my mod's along with the dyno sheets here

Based on my calculations from the 230/203 running on 5 cylinders, regardless of psi, if running on all 6 =

5 = 230
- ---
6 x

5x = 230*6
x = 230*6
-----
5
x = 276+hp!

I say the + because I'm sure running on 5 cylinders has some sort of effeciency loss associated with it OVER running on 6 cylinders. Not bad for a 2.5L SVT engine