H-Pipe, Crossovers, Etc. for 1998 Vert?

98GTBlkConv said:

I am not quite sure of the difference in all of the exhaust components of my 1998 GT convertible. I have done the "standard" mod of FM catbacks. I am considering a crossover or h-pipe, and do not know the differences in them. I understand that the car has 6 catalytics and, since VA is an emissions state, I don't believe I can remove the catalytics. So, what do you suggest I do as far as legal exhaust mods? Am I going to gain much by doing these mods? Also, I am considering the Accufab plenum and throttle body mod in the near future, so please suggest mods that will complement this change. Thanks!

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I battled with the X/H-Pipe question for about 2 months before making a decision. Being in California, I also had to consider emissions. I opted to go with the Magnaflow catted X and I am no where near disapointed. I spoke with the Magnaflow rep and he said it WILL pass the sniffer but FAIL the visual. So if you know a "smog friendly" shop, you should pass with no problems. Make sure you save your factory H just in case though.

As far as differences between the 2, quite honestly it's mainly sound. With an X you get more of an exotic sound (raspy with no cats) and an H is a more deeper sound. As far as HP/TQ gains, there isn't a big enough differance to use that as a deciding factor. When it comes to other mods to compliment the mid-pipe, I would vote to go with a PI intake/Plenum/TB combo. Just keep in mind our non-PI heads are the biggest restriction. So you can make everything breath very well but still be restricted by the heads. I hope my .02 helped you out.

Good luck

98GTBlkConv said:

Thanks for the reply. This has helped out some. I am wondering whether or not to focus elsewhere rather than put the money into the crossover or h-pipe. I am not sure how much gain I will get with this mod. Guess I'll keep doing research!

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If you looking for the best bang for the buck and looking to spend the least amount of money, here are my votes.

1) PI Intake (15 - 20 hp) - New from GEFRacing.com for 211 shipped to your door or you can hunt around for a used one.

2) PI Cam swap (15 hp) - Should be able to find a set of PI cams for around 150 bucks (I have a set for sale)

3) Mid-pipe ( about 5 hp with your mods) - Since you have to be smog cocious, your looking around 400 bucks for a mid pipe that has cats that WILL pass smog.

Hope this helps you decide your next mod.

98GTBlkConv

I don't have an answer for you but didn't want to highjack your thread with my own question. So.... you have a PM....

98GTBlkConv said:

I understand that the car has 6 catalytics and, since VA is an emissions state, I don't believe I can remove the catalytics.

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No emissions checks in southeast VA - where are you from?

I went with a MRT mid-pipe with cats, nice SOTP gain. A member here named trinity_gt I think just got a MRT catted pipe and was goign to dyno to see what kind of gain he got. You may want to keep an eye for that thread when it comes out.

NasaGT said:

No emissions checks in southeast VA - where are you from?

I went with a MRT mid-pipe with cats, nice SOTP gain. A member here named trinity_gt I think just got a MRT catted pipe and was goign to dyno to see what kind of gain he got. You may want to keep an eye for that thread when it comes out.

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I don't think that MRT makes a mid-pipe for a pre 99 do they?