Catback only Mod vs. Catback & X-Pipe Mod

[bluecoupdegrace]

My SVT Dealer has agreed to perform any upgrades to my exhaust system and still honor the warranty.

He also told me today that '03 Cobras that only have the catback replaced leaving the stock H-pipe are getting more HP and Torque gains than those replacing the catback and the H-pipe with an X-pipe.

Does this agree with any body else's experience out there ?

 

[sn8kbite]

i purchased a Bassani Offroad X-pipe and the Bassani catback system for my 03 cobra.
First i replaced the catbacks only because i wanted to see what difference everything made.
The car sounded great and had tons of low end torque a drastic step up from the factory catbacks.
Then i removed the factory H pipe and convertors and replaced them with the x-pipe,the car lost low end torque but seemed to breath better at wide open throttle.However the car sounded like royal shit so i put the factory H-pipe back on.
I am also running a superchip which has the MIL shut off.
If anyone is interested in a Bassani Offroad X-pipe you can
Email me at [email protected]

P.S...with the chip,and catbacks,and blower bypass,i have more power than the street tires can put to the ground,i was going to put a smaller blower pulley on next but now it will have to wait because i ordered 2 BFG drag radials in hopes of actually being able to put the power to the ground.

 

[bluecoupdegrace]

Thanks sb8kbite....

My SVT Dealer draws the line at a performance chip and pulley swap which he says will void the warranty if something goes wrong attributable to either.

There has got to be more people out there who can answer this post....or are some of you who have already purchased and installed the catback/x-pipe combo leary of finding out that you may have reduced your car's performance by doing so ?

I need more feedback...

 

[T3 Cobra]

Wow I have the catted x-pipe from bassani on order. I would like to know to?

 

[riplightning]

I was at Houston Performance today getting my magnaflow X-Pipe installed and one of the techs showed me dyno graphs of two different 03 Cobra's that dynoed stock, one at 340 hp and the other at 360 hp.

Then they overlayed the graph of the dyno after the magnaflow x-pipe and magnaflow cat back. The first car was at 371 the second at 382. No, I don't have print outs of these graphs, should of got them though, I thought it was interesting.

 

[bluecoupdegrace]

riplightening:

Do you mean that both of them got the magnaflow x-pipe and magnaflow cat back and that the one that dyno'd at 340 stock improved to 371 and the other at 360 stock went to 382 -- which were improvements of 31 and 22 hp respectively ?

BTW...what were your before and after numbers ?

 

[riplightning]

bluecoupdegrace:

Both got the full meal deal. I asked about the difference in the numbers and didn't get a good explanation.

If I get a chance I will go by there tommorrow and see if they will print the graphs off for me and I will scan'em in so I can post them.

I didn't dyno my car, didn't have time today was getting the install done between appointments.

 

[03DOHC]

I could be wrong, but I believe the entire exhaust and intake system has room for LOTS of improvment. This has been stated by Mr. Coletti, many dyno sheets, and lots of people on this forum.

 

[bluecoupdegrace]

03DOHC:

Well...being the cautious type...and being content to let others go where no man has gone before...before I do...I'm attempting to learn from the experience of the "pioneers" who have made exhaust mods to date...

There is either 1) an inconsistency in production quality that varies from Cobra to Cobra...2) an inconsistency in dynos that varies from shop to shop, or 3) a specific combination of exhaust components that gives optimum performance.

I'm interested in 3) but it seems in attaining that information we have to take into account the possibility of 1) and 2).

Being the anal, methodical German type, I wish someone had established a process whereby we all did our mods, thereby allowing us to learn what did and didn't work.

For example, before applying the chip and pulley mods, what would be the optimal exhaust set-up through trial and error.

Some shop out there could gain a whole lot of marketable credibility by buying a set of all the exhaust products and testing them out in an audited controlled dyno environment and publishing the results.

 

[sn8kbite]

Let me clarify what i stated about the offroad X-pipe.
The car lost bottom end torque with the X-pipe,thats not to say it lost horsepower.It simply changed the torque curve,moved the torque upwards into midrange area.
However it did make the car sound like total shit.
The largest and most noticable increase in horsepower was from replacing the factory catback system,not the X-pipe.

 

[Blue03Cobra]

Originally posted by riplightning
I was at Houston Performance today getting my magnaflow X-Pipe installed and one of the techs showed me dyno graphs of two different 03 Cobra's that dynoed stock, one at 340 hp and the other at 360 hp.

Then they overlayed the graph of the dyno after the magnaflow x-pipe and magnaflow cat back. The first car was at 371 the second at 382. No, I don't have print outs of these graphs, should of got them though, I thought it was interesting.

Looks like the 340 car may have had the infamous clogged cats, from the factory. Comparing the two, once the stock pipes were replaced, you have virtually identical results...

 

[Tundra]

<-- Lightning owner, 03Cobra bolt on mechanic. How's everyone doing?

I just installed a bassani catback system on my buddy's 03Cobra today. Earlier today we went and picked the car up from Valley Motorsports, a Pontiac dealership. We are pretty tight with the owner, and he intalled a Dr. Gas X pipe that was ordered a month ago. The good doctor sent us the wrong cats so we had to go with an off road X (no cats). Much to my friends horror, the stock front two cats were blown and clogged up the second two. Good thing we had the car worked on.

With the stock 'cat' back the car was much stronger than I had ever seen it, and I had previously put a 1/2 a carlength on a C5 from a 4000 to 6000 rpm roll in first when the car was stock. The car was alive!

Then I went and installed his Basani Cat Back. The mufflers were chamberless, like a 3" straw. The baffles in the tips looked like they provided more back pressure. whats losing 5lbs of torque down low when you have close to 400? Well, I installed the system and it is BADASS. He got it through a group buy going on here a couple weeks ago.

This is where the deal got good. It just so happened that I was in Los Angeles when Basani packaged his order so I went and picked it up. While I was there, I had a good look see at their x pipes. After playing with a Dr. Gas X pipe and looking at the bassani x pipe, I have to be honest. The Bassani looks like a massaged H pipe, whereas the Dr. Gas really looks more like a true X. You'd have to see them both in person.

Dont get me wrong, Bassani makes a bad ass system, but I am glad he went with Dr. Gas.

In conlcusion, we went and tested the modded Cobra against my Lightning that runs consisten 13.1-13.2@103-104 with its chip, 90mm mass air.

WAIT AND SEE THE VIDS

 

[Cobra'03]

Originally posted by sn8kbite
Let me clarify what i stated about the offroad X-pipe.
The car lost bottom end torque with the X-pipe,thats not to say it lost horsepower.It simply changed the torque curve,moved the torque upwards into midrange area.
However it did make the car sound like total shit.
The largest and most noticable increase in horsepower was from replacing the factory catback system,not the X-pipe.

If it lost torque, it lost HP in the same RPM range. I am not so sure I would want to add an aftermarket X-pipe if that is the case - for street driving, it might be a net loss in performance. BTW, the new MM&FF has a tech letter response that does not recommend removing catalytic converters (that is, an O/R pipe) - they say the gain is tiny, and not worth the pollution it hands to everyone else.

 

[Steve Snake Driver]

I replaced the stock cat back with an 01 Bassani catback. With this, and just the drop-in K&N filter (no silencer) I dynoed 396.2 rwhp STD with the stock cat pipe. Sorry, no torque numbers, they were having trouble with the COP wire pickup. Don't have any unmodified numbers. Only reason I managed to get a dyno at this time was that it was a portable dynojet at a carshow. Just don't have any close and have been busy with work

 

[riplightning]

I spoke with the guy at Houston Performance that did the dyno on both 03 cobra's. He said that since the difference in the stock 340 vs the stock 360 horsepower is exactly 20 HP then his conclusion is that it has to do with the EEC and programming. In other words inconcistency or difference in the way the computer was programed.

I think I also read something about this different EEC program on one of the post about chips on this board?

 

[SVTdubs]

I am buying the magnaflow catback and also the magnaflow x pipe with high flow cats. When I get it, I will dyno stock, then with the catback, then with the x pipe and post the results.

It might take some time due to me going to college and me taking the SVT Contour and leaving the Cobra behind =(

 

[03SoCalCobra]

I was chatting with Jeromy at JDM when I ordered my flip-chip. One program is for the 4#, Bassani cat pipe & catback; the other is for the 6# pulley and the bassani cats removed. They mentioned that they've seen a loss in power when the cats are not present, something about the motor liking a little backpressure for the low end.