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3" Catback Exhaust Install Issue.

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Drop Top Road Trip

Proven Member
230
59
Oct 13, 2015
St. Louis, Missouri
So, finally got the old stock exhaust off the '99 GST Spyder. Took lots of patients, some PB Blaster, a breaker bar and a hack saw...but it IS off.

Anybody else find that the fat 3" pipe and flange on their muffler doesn't fit through the space between the rear suspension cross member, fuel tank and the body?

I'm doing this in my driveway and I'm wondering if I get the car high enough to attack the problem at a different angle, if maybe then that big flange might slip right through there...or do I need to lower the cross member - or perhaps lower and skootch the fuel tank out of the way?

Anybody else have any issues with a 3" exhaust driveway install?
 
I did mine in my driveway without any issues. Mine is a GSX though but I would highly doubt that you would need to lower the tank or touch the crossmember.
What exhaust are you trying to install? And do you have any pics?
 
Even most eBay catbacks fit perfectly. There's usually a dent on the bend of pipe next to tank. I put my whole exhaust on (no cat) my Tsi fwd In about 20 mins on jack stands. Are you sure youre lining it up right? You gotta kinda force that flange and angle the muffler to get it through. Hang the muffler and then attach the middle pipe.
 
Yeah. I'd lower the crossmember a hair to give you some space to work in. GST exhaust goes above, GSX goes below. Sucks that I have to buy a whole new system when I convert. (Oh well.). On my other car (not a DSM), I ended up dropping the crossmember as well. Talk about no space on that one. Which system did you get anyway?
 
Even most eBay catbacks fit perfectly. There's usually a dent on the bend of pipe next to tank. I put my whole exhaust on (no cat) my Tsi fwd In about 20 mins on jack stands. Are you sure youre lining it up right? You gotta kinda force that flange and angle the muffler to get it through. Hang the muffler and then attach the middle pipe.

I've only given the muffler pipe / flange a tentative try as it clearly was contacting everything and I wasn't sure as to weather or not I should be making room by lowering something. My next try will be with the back end MUCH higher off the ground so that I can try alternative angles. Just wanted a little reassurance before doing so. Thanks.
 
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Yeah. I'd lower the crossmember a hair to give you some space to work in. GST exhaust goes above, GSX goes below. Sucks that I have to buy a whole new system when I convert. (Oh well.). On my other car (not a DSM), I ended up dropping the crossmember as well. Talk about no space on that one. Which system did you get anyway?

I'm gonna give it another try with everything in place before lowering the cross member. Seems others have been successful.

I'm installing a beautiful SRS 3" Catback ($250 - Amazon). It's welds aren't the prettiest I've ever seen, but the entire package looks like it'll do the trick.
 
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The link was to show that you need the rear of the car up as high as you can get. +1 on lowering the crossmember. It should be 4 bolts.
 
I feel your pain man. I install my megan racing 3inch cat back last week. The muffler took me 30 mins of messing with it for it to go over. I loosend the 4 bolts holding that metal bar that goes all the way across and let it swing down. Don't know if this will help but when I got the exhaust over, the muffler oriented towards the driver rear tire then I swung it back where it shoukd be. As far as height goes the car was jacked up with a 3 ton jack with 3 blocks of 4x2 on top of it. Good luck!!
 
I feel your pain man. I install my megan racing 3inch cat back last week. The muffler took me 30 mins of messing with it for it to go over. I loosend the 4 bolts holding that metal bar that goes all the way across and let it swing down. Don't know if this will help but when I got the exhaust over, the muffler oriented towards the driver rear tire then I swung it back where it shoukd be. As far as height goes the car was jacked up with a 3 ton jack with 3 blocks of 4x2 on top of it. Good luck!!

Perfect reply! Thanks for the added info.
 
Perfect reply! Thanks for the added info.
As high as the car was the muffler tip was still touching the ground when I got it on. Its been a while since I cursed that much getting this thing on. Oh and one more thing if you look at the bottom of the trunk you will see a widened area mine looked triangular shaped. That's precisely where my aftermarket exhaust cleared the cross member.
 
Here are some quick pics of the problem area, for those who have not tried to squeeze a 3" exhaust into the space allowed by Mitsubishi for the stock 2" pipe and flange.

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Yeah you have to have the pipe pointed straight up for it to fit in there. Keep the ass end in the air because you have to rotate the crap out of the pipe to get it to correctly fit. It was hell getting it in there, it was worse trying to rotate it to get it to line up. Mine was a 109.99 ebay special

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Here are some wider shots (had camera on max rez - pics too big - texted them to myself to resize).

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Yeah. I had that issue too I think I just loosened the sub-frame bolts on the driver side a bit and it let me slide the flange through. That bend makes it difficult to put in a different muffler too because of the angle. I heard you can use an AWD catback and it slides under the subframe instead but I never confirmed that
 
Ditto, it's just about getting the flange at the correct angle to feed it through there. The pipe fits fine the flange just takes some time. You can rotate the exhaust once the flange gets through there so don't worry about feeding the pipe through there to line it up correctly.

Again you basically need to have that section pointed straight up in the air so that you can get one side of the flange on the top of the subframe, then rotate the pipe so that the second ear on the flange goes in. It really was some thing you need a lift for, but I used a floor jack and Jack stands. I remember the car being able to "teeter" on the jack stands if I pulled down hard on the exhaust

If you tap out and take it to a muffler shop they will cut up that section and then patch it with some cheap piping and tell you about how bad the exhaust was and take another $120 from you
 
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Thanks so much everybody for the support and good advice. I've got some "before" video from behind the car as well as on the road that I'll be posting with "after" video once I get that fat drain pipe squeezed in there.

Working on this car is kind of chaotic, I'm also planning to Dye and waterproof the top soon as well as install a set of leather seats from a Mini Cooper (our stock leather seats kinda suck, right?)....AND I just picked up a set of Rays / Infiniti G35 Forged 19"s that will be going on soon.

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