Removed Hi-Flow Cats for Bassani X w/no cats

[SnakeCharmer]

This week I decded to remove my brand new Magnaflow x pipe with hi -flow cats and replaced it with Bassani's modular X pipe with removable cats. After the cats were removed the car ran horribly. Big drop in power, fuel smell in cabin(running rich), lousy exhaust note. The car was an absolute monster prior to the change.

[SnakeCharmer]

To Finish my post -here is the question- Has anyone with the Diablosport chip, 2.81 pulley and throttle body had a similar experience?? and if you did, did retuning the chip help? I am bring the car to Diablosport tomorrow to check A/F mix, Dyno HP, etc. Thanks Guys

[5.0 guy]

At least you tried, and are saving money for me, I was about to order the non catted X, but Norcal had mentioned a while back that the performance was better with them, it does make sense, the car needs back pressure to obtain optimum boost. thanks for sharring your test!

[anvrsy red vertble]

Hey SnakeCharmer: When you removed the cats, did you use the O2 mil eliminators? I'm not an EFI guru, but I believe if you didn't, the computer could not compensate correctly to deliver the proper A/F ratio! This would definetely effect performance. Let us know what Diablosport has to say.

[HotRodHarry]

I had no problems with my full bassani exhaust..headers/mid pipe with no cats and catback.....sound clips are on my www.HotRodHarrys.com webpage in my 2003 Cobra Area...Its all in the tune and resetting your computer to changes

[SnakeCharmer]

Thanks guys for the replies-The a/f was dialed in at 12 and I picked up about 80 HP and Ft lbs. of torque. The fumes are evident in the cabin, but the HP/TQ curves responded well to more fuel. The car sounds good ...but I got edged by a Cobra tonite that I beat before eliminating the cats... so I might go to Steeda, put the cats back and hit the Dyno again. More money again. My 01 Viper did not eat as much cash, but that is because I did not mod the GTS.

[5.0 guy]

I'm interested to hear how it turns out, the exhaust note must have been much louder without the cats I bet! harry, did you do a dyno with and without the cats, I've read several times that the car doesn't perform as well without the cats, I'm curious as for I am about to order a full bassani exhaust with ceramic coated headers. I like the option to be able to remove the cats if you want, Norcal has that setup and talked me into it for sure. I don't usually run cats on my stangs, so I definately will look into this a little better!

[SnakeCharmer]

hey 5.0 Guy- just an fyi. Friday I am going to Steeda with the Bassani cats that came with the 5 piece modular(onroad,O/R) kit(it's a week old and cost $549 plus tax from Steeda) and I am also taking my Magnaflow catted X-pipe so I can swap em and Dyno test it all.Bassani no cats, Bassani w/ cats, Magnaflow with cats The DiabloSport tuner said some cars react fine to the off road kit, and someother don't. If I sell the new bassani kit and you want to save some money let me know- it is brand new.

[norcal_cobra]

I ran my N/A 5.0 without cats and made more power. But this S/C 4.6 seems to run better with a little backpressure, so I am running the Bassani cats. If you look at the numbers, running without cats on these cars doesn't work well on mildy modified cars (cai, headers, exhaust, pulley, chip). I dyno'd my car at the same time they were doing another 03 Cobra with the same setup as me except he had no cats and a Magnaflow catback. I made slightly more HP and TQ than the other car. One would have expected the other car to make better numbers without the cats.

-norcal_cobra

[5.0 guy]

Norcal, my five O' has a complete Mac setup, shorties, H-pipe(no Cats), 2.5 inch cat back with two baffle mufflers and it runs great. I took the H-pipe off and reinstalled the cats for emissions back in AZ and the car lost all of its exhaust note. I didn't expect the H-pipe to make that much of a difference with the sound. Snake, let me know if you decide to sell, I would be interested, can't wait to hear how the dyno comes out!:cbra:

[norcal_cobra]

I've had the same experience with my 5.0. It also has shorties, MAC OR H-pipe, and 2 chamber Flowmaster catback.

The other 03 without cats that dynod the same day as I did didn't sound any louder to me, atleast not at full throttle. But my Bassani mufflers are a little louder than the Magnaflows he had and also have a different pitch to them.

-norcal_cobra

[5.0 guy]

Interesting! I'm pissed about my Nittos right now, so I think I will stay away from the computer for a little while, talk with you later!
John

[SnakeCharmer]

Well good news- I went to Steeda and Sam(great tech)put the bassani cats on and Dynoed the car. It picked up nicely, but we had to reprogram the chip which had the car running way to rich. After he put the "old faithful" program back in (a dead on tune) the car pulled 477rwhp/498rwtq with a huge difference in the midrange especially- That's it- the cats stay on!!

[5.0 guy]

Very nice!, I expected 500rwh with a 2.8,throttle body and exhaust,What type of throttle body did you upgrade to and have you done your headers yet?, if not definately go with ceramic coated ones to avoid as much heat as possible.:tmb: Very cool numbers though! how many people can post a 450+RWH car that is almost stock on a forum(other than our of course!!!) not very many, nice job!

[SnakeCharmer]

Thanks 5.0... Most of the accufab throttle body cars with 2.8 that I have seen still come in under 500 rwhp. I did hit 498 rwtq with hot South Florida weather and inadequate pull times between runs which is probably worth a few HP I admit it would be nice to hit, but I would probably need to take the Apten route and improve SC efficiency to hit the 500 club. I kept the Bassani exhaust so I can easily make the the switch to headers as the modular kit is designed for it.:)

[5.0 guy]

Checkout DaleM's list of mods, I think he told me he was around 540RWH, but he's added alot of parts. I want the kenne Bell setup but since I'm waiting to order an 06 and need a new trans and clutch for the 88', I'll probably go with the ported Eaton like yourself. After paying off the car and suspension upgrades and cosmetic upgrades this year, a Kenney B seems less desireable. Plus I like the clean factory look of the Eaton and I want to have her black powder coated like the saleen twin screws versions on the S281 E's.
John
I wonder if long tubes would push you over the 500 mark, all you are missing is a PRO M meter and you will have all the common addons!

[rhorton]

have seen the whipple supercharger? I saw one this weekend in a 03 cobra. i dont have picture.

[norcal_cobra]

You'll definitely lose torque with the headers....

-norcal_cobra

[390woah]

excellent thread, Im learning alot! Quick question, Im assuming you have hi-flow cats on your x-pipe?