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-   -   My Brola XR-1 exploded today (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/my-brola-xr-1-exploded-today-756117/)

pd_day 05-14-08 03:26 PM

My Brola XR-1 exploded today
 
5 Attachment(s)
My Borla XR-1 finally gave in today ..... It was sitting after a SDJ header. I probably had it on the car for maybe 2 yrs. Pictures will take a thousand worlds.

I am thinking I should go back to Racing Beat's mild steel so this does not happen again .....

pd_day 05-14-08 03:28 PM

4 Attachment(s)
More pics...

Do you guys think this is due to heat, too much exhaust movement or defect?

Current exhaust setup is

SDJ header -> Borla XR-1 -> Stock cat back.

10aeRX7 05-14-08 04:42 PM

i would throw a magnaflow in there. u can pick them up at a reasonable price and they last too. thats what i have and i know a few others that have done the same. plus it quiet's down the car too

RacerXtreme7 05-14-08 05:38 PM

Holy Shit!! I'd give Borla a call. I bet they'll replace it for you.

~Mike................

Icemark 05-14-08 06:11 PM

Looks like there is some tuning and running way rich issues

pd_day 05-14-08 06:13 PM

Unless my injectors are stuck open, a/f should be ok.
When I was at the dyno, I tuned it to 13.5 with a wideband on my S-AFC ...

Hmm ...I don't get flames and I don't get pops... maybe indeed one of the injectors are stuck open?

This just happened after a lapping session.

Black91n/a 05-14-08 07:28 PM

My guess would be exhaust movement as the culprit. The exhaust is soft mounted, yet there's no flex joints in there, so all that movement's taken up by flexing, mostly in the weakest part, which would seem to be that muffler as a pre-silencer.

ramses666 05-14-08 07:39 PM

I guess you got what you paid for? Any compaints? How long was it in service? Would you buy another one considering the longevity of the part? Is something blowing up in there? I would suppose once it cracked that some air got in there during deceleration and the exploded under throttle?

Ramses666

ericgrau 05-14-08 07:53 PM

Hard to tell from the pics if that's a crack or a tear. If you get a brittle-like crack in a ductile (flexible) material - which normally bends/etc. not cracks - then it came from fatigue. Fatigue would be from the thing flexing back and forth, or repeated pressure fluctuations. If it ripped apart from too much pressure, then it should tear apart lengthwise, which didn't happen. Though maybe the metal's thinner in the other direction; it did break along the letter "L". I'm more engineer than car guy, btw, these are just guesses.

hondahater 05-14-08 08:11 PM


Originally Posted by ramses666 (Post 8191829)
I guess you got what you paid for?
Ramses666

??? Borla midpipes are not cheap!

RoTa7 05-14-08 08:28 PM

they will replace that for free. they have a million mile warranty.

ericgrau 05-14-08 08:42 PM


Originally Posted by pd_day (Post 8190925)
More pics...

Do you guys think this is due to heat, too much exhaust movement or defect?

Current exhaust setup is

SDJ header -> Borla XR-1 -> Stock cat back.

Hmm, you're asking the right questions I think. If you're missing exhaust hangers that would greatly increase exhaust movement, causing fatigue and making a sharp brittle like crack around the circumferance, like yours. The highest fatigue would be in the middle of the exhaust if you only supported the exhaust at the engine and mufflers. If you had no hangers at all then you'd have more bending fatigue closest to the engine. It broke along the "L", which is the "defect" and a weak point, but that doesn't mean Borla didn't design the weakest part to be strong enough. High heat would make the metal expand and soften, so maybe that combined with exhaust movement (normal or otherwise) could have done something. Again, just guesses.

gracer7-rx7 05-14-08 08:45 PM

I blew one in the same manner on one of my Turbo IIs back in the day.

MaczPayne 05-14-08 08:50 PM

That muffler tore open. Borla should be able to replace it for ya.

fastrotaries 05-15-08 07:37 AM

Borla will warranty that. I think it's too close to the headers, and you have no flex allotment. Flex pipes or donuts. I've had one of those on my car for about 5yrs. Those are some of the best pieces of sound control for vehicles on the market today.


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