Ok, as hard as it is to post about this, I am going to anyway.

I dyno'd the 99 A4 TA yesterday, and was highly disappointed. I don't want to talk about numbers, let's just say they were low. Almost like a cylinder was missing. Under 330.

ANYWAY.

Here are the mods worth mentioning:

Fast intake, K&N FIPK, tb bypass, LS1 hot cam, Meizere EW, Bassani y pipe, Flowtrasher, and excellent tuning.

My tuner said I could gain around 30hp w/ a better exhaust. I KNOW that flowmaster is trash, it has been on there for 3 years. I still have the stock manifolds, just added the bassani y pipe and the flowtrash.

I am assuming I could gain a LOT from an exhaust upgrade. But which would show the most improvement first? A good flowing catback or headers? I can't do both at the same time, so I really need some advice.

I thought about getting a Magnaflow cat back from tbyrne today, since he is having a good sale. And maybe LT's next year. Just trying to figure out what is going on.

The tuning on the car was EXCELLENT and according to the computer the engine was working excellent and all the mods were working very well together. He said the exhaust was really holding me back. Kinda like a coffee straw.

I also have to take into account that I had TT2's on the back w/ 315's. He said they cost me about 8-10hp.

Any advice from yall would be great. That dyno hurt my feelings! I almost had the damn flowtrash sawed off before I left!

I DID do some searching and it looked like everyone on here was pretty happy w/ the Magnaflow. And I know dyno#'s are mainly for bragging rights, which the only reason we dynoed it was for tuning.
But the car runs GREAT on the street, I am very happy w/ the performance in that aspect.

Thanks in advance.

 

You will get hardly no benifit from long tubes with that cat back on so unless you want to run a cutout to bypass the Flowmaster then it has to go first.
The Bassani 2 1/2" y-pipe is one of the best on the market for it size so that will do 'till the headers come. As a matter of fact I had thier OR Y on my 2000 with a Loudmouth and dynoed 312 on a dyno jet. So get the good cat back and put the long tubes on when $$$ allow.

 

That is exactly what I was thinking. The cat back first. I will do that, and I am pretty sure I am going w/ the Magnaflow. Can't wait to get that flowmaster OFF the car. I really am not interested in a cutout, I have one on the LT1 and that is enough

So you agree the exhaust is killing my numbers as well? Should I feel the difference on the street w/ the Magnaflow?

Thanks!

 

Yes and yes. Heck when you get the long tubes with the Magnaflow you'll need to touch up your tune.
Buddy had an LT1 mild heads/cam car with long tubes, 3" Y-pipe, and a Flowmaster cat back. Opening his cutout got him 2.5 mph at the track. That's 25 hp gained just from bypassing the FLowmaster.

 

Definitely ditch the Flowmaster.

I've heard that the Fast intake manifold is overkill for a stock-cube motor, and that it can cost you power. Maybe you should switch to an LS6?

My lid-and-catback '02 put 325/343 to the wheels last weekend.

You weren't on a Mustang dyno, were you?

 

WOW. I can't believe that flowmaster is THAT bad. I wanted to kick myself in the **** so MUCH yesterday. I figured w/ the long tubes and magnaflow I would need extra tuning, but that is fine w/ me.

That is an amazing gain even for an LT1 car!

 

I have the 78 FAST. The 90/90 setup is an overkill, but not the 78. I installed the FAST b/c I received an excellent deal on it. Or I would have went w/ the LS6.

Those are EXCELLENT numbers you put down. Mine made 1 less hp and less torque. Sad.

It was a Dynajet...

 

Switch to a Corsa!

Mine's an M6... that's worth a few to the wheels as well.

 

Right now the Corsa is about $350 more than the Magnaflow, so I can't justify it....I would rather take that extra and use it for the LT's. Although I like Corsa, I have heard it on a 02 SS w/ H/C. It sounded great!

 

I've heard that the Magnaflow setup flows just as well as the Corsa, but I haven't (personally) seen proof. Let us know how it goes!

 

just buy the magnaflow muffler...no need to swap the entire catback just for a poor flowing muffler.

then you could probably afford the headers sooner.

but with alll bolt ons, cam, big intake...you are REALLY choking the car with those manifolds.

 

you need a 4 inch Mufflex exhaust, they will support more horsepower then you will ever make..... I just happen to have a complete exhaust and a ypipe for headers. hit me up if your interested.

 

My thoughts exactly.

 

Well, I found a killer deal on the Magnaflow. And no one could beat it. It even included FREE UPS shipping. Almost UNDER $300 Can't mention the vendors name, but it just takes some persistance in looking.

I will make an update to this thread by next week

Thanks for all the input on this issue!!

 

Have you considered the hooker aero chamber muffler? It flows great and sounds real nice, sorta like the big block chevelles from the late 60's to early 70's. They are not to exspensive , so you can put more of your money towards LT's. Good luck!