Ryanmgaspard

iTrader: (6)

I wanna run a 2.5" true duals X pipe from the factory cats to the rear center exit. I have 2 Moroso Spiral Flows. Should I keep the factory cats in tact or replace with high flow ones from Magnaflow? Will I lose hp goin with the Magnaflows or gain, car is stock? How much is lost/gained staying with the factory cats? Also if I gutted the factory cats will this cause my SES light to come on? Will gutted cats flow better than the performance ones? The minimal sound difference isn't my concern. I want factory or better low end power. Appreciate the help!

jlashley2001ss

iTrader: (5)

i would no doubt go with the hi-flow cats. you will gain some hp switching to the hi-flow cats, but not significant change. If you gut the cats you will have a SES light, but you can get a tune and get your tuner to "tune" it out. I would go ahead and get headers while your at it but i dont know what ur plans are with the ride. Hope this helps!

GreenBlood

iTrader: (6)

headers FTW...but if ur not going that route...then definitely get he highflow cats...

Ryanmgaspard

iTrader: (6)

I like headers but I really don't wanna lose ground clearance. Are the headers we don't speak of fitting better than the of LT's? Won't headers also require a tune and a SES light? If I wanted to keep my stock manifolds, what size inlet on the cat would I need if I went aftermarket?

01bird58

iTrader: (9)

You won't lose ground clearance as long as you stay away from SLP Longtubes! There are tons of options that will work for you very well. Headers do not require a tune, but you will need O2 sensors and your local tuner will have to zap out some codes that will flash in order to pass an OBDII inspection. Im pretty sure the cat inlet size would be 3".

lsx24

iTrader: (45)

I'm fairly certain you want 2.5" for stock and 3" for longtubes. And yes I would run highflow cats. Gutted cats are basically running no cats, some people like to leave them on for inspection but that's not very wise.

Headers don't necessarily require a tune but it's good to get one for it. I would do all the boltons first then get a tune...Headers won't set off the light but ditching your rear 02 sensors will but that can be tuned out with a tuner.

Ryanmgaspard

iTrader: (6)

I was also have the supplies to build my own exhaust. I plan to use the stock y pipe as an example. I need to copy the way the bends are but with (2) 2.5" pipes instead of the 3. I can pick up all the piping and bends for under $200 i'm positive on. This seems more logical then to spend $600 for a mandrel bent system from a pro. What kind of welder do I need. At the shop they have alot of welders.

orangeapeel

iTrader: (18)

What are you trying to get around doing exactly?

Ryanmgaspard

iTrader: (6)

Nothing really. I think i would be more cost effective and experimental to build one myself. Then I can make a list of all the parts needed and I'll do a write up.

JEB Garner

Ryanmgaspard, I have duals with 2 1/2 inch pipes, stock manifolds and stock catalytic converters. I ran both pipes down the passangers side and over the axle. Used two straight through noise cancelling mufflers, one placed on either side of the rear tub. Picked 15 horsepower at the rear wheels. Not to loud, just a sweet muscle car sound. As for ground clearance, it is far better than with that stupid, power robbing, stock "Y" pipe system.