98gt exhaust upgrade

wade73 · 04-15-2002, 03:46 PM

i am in the market for an exhaust upgrade. as far as i can tell, the only real difference between borla, flowmaster, etc is tone and volume, as they both generate about the same hp gains. what are people doing to circumvent the 6 catalytic converters on the 4.6's? i was checking into the borla exhaust, they want close to 900 clams for a cat back system. if its from the cats back, as the name suggest, then what would be the difference in putting the borla system on rather than just changing the mufflers?

the cats are the most restrictive i would think, not necessarily the stock mufflers.

Hammer · 04-15-2002, 05:15 PM

The most restrictive part of the exhaust system are the cats...

I'd go for an X\H-pipe with high flow cats before worrying about mufflers...

You won't see any gain from a cat-back system, but a less restrictive X\H\cat system should net you a few horses...

ideally, you'd want to replace the X\H-pipe and cat-back system at the same time to ease installation (bolt-on) and maintain a constant exhaust diameter...

wade73 · 04-15-2002, 09:45 PM

thanks for the info...what are the advantages, if any between the x and h pipe?

are there ways around the six cats? or must they be intact?

Hammer · 04-15-2002, 09:54 PM

The six cats need to be REMOVED, and replaced with two high-flow cats...

They will usually come with an X\H pipe setup...

The X and H pipes usually give comparable gains...

The H will have a bit more low end grunt and the X will live a bit better up high... Its just how you want your setup to be....

wade73 · 04-18-2002, 11:19 AM

cost being a minor consideration, what manufacturer would you recommend for the exhaust? i have really on found steeda's hi-flo cats available, and noone elses (saleens website was down as of last nite), and roush's stuff is thru the roof expensive

tireburner163 · 04-18-2002, 01:57 PM

Do yourself a favor. Get a off-road H or X pipe. They have no cat's, so even less restriction. Plus they are a HECK of a lot cheaper(125-150 bucks).

wade73 · 04-18-2002, 02:23 PM

i thought about that...but each cat (i am speculating here) probably has some sort of sensor on it, and if they are unplugged then i get to look a check engine light all the time. that in and of itself is no big deal, but could mask a problem at a later date

98SteedaGT · 04-18-2002, 02:45 PM

I believe they make a component called an MIL Eliminator. I think it is used when you do not have cats and the rear two O2 Sensors. I am not sure of this as I still have all four of mine, I just went with BBK Stainless H-Pipe w/Hi-Flow cats (2) not 6. You may want to look for the eliminators and see if that will help.... I am fighting the Check Engine Light myself, but mine is being caused from the new MAF, Underdrives and Timing Advance I put on a couple days ago. The computer and I are going to sit down and have a nice little chat about it playing nice with the new parts.. hehe

98SteedaGT · 04-18-2002, 02:48 PM

http://www.mileliminators.com/index.html

Here's the info on the MIL Eliminators, hope this helps you out...

wade73 · 04-18-2002, 05:00 PM

thanks man... i really appreciate the help

04-15-2002, 03:46 PM	#1
wade73 Registered Member Join Date: Apr 2002 Location: Mobile, Al Posts: 108	98gt exhaust upgrade i am in the market for an exhaust upgrade. as far as i can tell, the only real difference between borla, flowmaster, etc is tone and volume, as they both generate about the same hp gains. what are people doing to circumvent the 6 catalytic converters on the 4.6's? i was checking into the borla exhaust, they want close to 900 clams for a cat back system. if its from the cats back, as the name suggest, then what would be the difference in putting the borla system on rather than just changing the mufflers? the cats are the most restrictive i would think, not necessarily the stock mufflers.

04-15-2002, 05:15 PM	#2
Hammer AKA "Dr. Evil" Join Date: Feb 1999 Location: South Fork Ranch Posts: 1,721	The most restrictive part of the exhaust system are the cats... I'd go for an X\H-pipe with high flow cats before worrying about mufflers... You won't see any gain from a cat-back system, but a less restrictive X\H\cat system should net you a few horses... ideally, you'd want to replace the X\H-pipe and cat-back system at the same time to ease installation (bolt-on) and maintain a constant exhaust diameter... __________________ Uncle Sam "What the hell is up with all the gauges? Calling Captain Kirk, your ride awaits... Phasers on stun...."

04-15-2002, 09:45 PM	#3
wade73 Registered Member Join Date: Apr 2002 Location: Mobile, Al Posts: 108	exhaust upgrade thanks for the info...what are the advantages, if any between the x and h pipe? are there ways around the six cats? or must they be intact?

04-15-2002, 09:54 PM	#4
Hammer AKA "Dr. Evil" Join Date: Feb 1999 Location: South Fork Ranch Posts: 1,721	The six cats need to be REMOVED, and replaced with two high-flow cats... They will usually come with an X\H pipe setup... The X and H pipes usually give comparable gains... The H will have a bit more low end grunt and the X will live a bit better up high... Its just how you want your setup to be.... __________________ Uncle Sam "What the hell is up with all the gauges? Calling Captain Kirk, your ride awaits... Phasers on stun...."

04-18-2002, 11:19 AM	#5
wade73 Registered Member Join Date: Apr 2002 Location: Mobile, Al Posts: 108	cost being a minor consideration, what manufacturer would you recommend for the exhaust? i have really on found steeda's hi-flo cats available, and noone elses (saleens website was down as of last nite), and roush's stuff is thru the roof expensive __________________ 98 GT - Usual "Get in, sit down, shut up and HANG ON"

04-18-2002, 01:57 PM	#6
tireburner163 It's a lot like a race car Join Date: Aug 2000 Location: Meridian, MS Posts: 4,130	Do yourself a favor. Get a off-road H or X pipe. They have no cat's, so even less restriction. Plus they are a HECK of a lot cheaper(125-150 bucks). __________________ 1987 Buick T-type 1998 HD Electra Elide

04-18-2002, 02:23 PM	#7
wade73 Registered Member Join Date: Apr 2002 Location: Mobile, Al Posts: 108	i thought about that...but each cat (i am speculating here) probably has some sort of sensor on it, and if they are unplugged then i get to look a check engine light all the time. that in and of itself is no big deal, but could mask a problem at a later date __________________ 98 GT - Usual "Get in, sit down, shut up and HANG ON"

04-18-2002, 02:45 PM	#8
98SteedaGT Registered Member Join Date: Jan 2002 Location: Texas Posts: 330	I believe they make a component called an MIL Eliminator. I think it is used when you do not have cats and the rear two O2 Sensors. I am not sure of this as I still have all four of mine, I just went with BBK Stainless H-Pipe w/Hi-Flow cats (2) not 6. You may want to look for the eliminators and see if that will help.... I am fighting the Check Engine Light myself, but mine is being caused from the new MAF, Underdrives and Timing Advance I put on a couple days ago. The computer and I are going to sit down and have a nice little chat about it playing nice with the new parts.. hehe __________________ // 1998 GT-Steeda Conversion \\ -- Sold // Now own 2001 F-150 SuperCrew 5.4L \\

04-18-2002, 02:48 PM	#9
98SteedaGT Registered Member Join Date: Jan 2002 Location: Texas Posts: 330	Website Address http://www.mileliminators.com/index.html Here's the info on the MIL Eliminators, hope this helps you out... __________________ // 1998 GT-Steeda Conversion \\ -- Sold // Now own 2001 F-150 SuperCrew 5.4L \\

04-18-2002, 05:00 PM	#10
wade73 Registered Member Join Date: Apr 2002 Location: Mobile, Al Posts: 108	thanks man... i really appreciate the help __________________ 98 GT - Usual "Get in, sit down, shut up and HANG ON"

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