81 dual exhaust

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Jun 27, 2003 | 06:39 PM

Ben Taylor

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From: Camino CA

81 dual exhaust

I want to put dual exhaust on my 81 with a power driver's seat. Do I have to route both the exhaust pipes under the passenger seat like the stock setup, or is there a way to make straight pipes on both sides?

Jun 27, 2003 | 08:09 PM

Dalannex

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From: Northeast South Dakota

Re: 81 dual exhaust (Ben Taylor)

I think you needs to run both pipes on the passenger side. i don't remember what it is, but seems to me there is something in the way on the driver side preventing it from running that way. Mine are both on the passenger side. For some reason the crossmember comes to mind.

-Justin

Jun 28, 2003 | 12:57 AM

Glensgages

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From: State of Confusion

Re: 81 dual exhaust (Ben Taylor)

I was told that to provide more driver-side head room, driver-side seats are a bit 'lower', mandating all exhaust goes down passenger-side.Sounds plausible..... :confused:

Jun 28, 2003 | 01:00 AM

BSeery

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From: Exiled to Richmond, VA - Finally sold my house in Murfreesboro, TN ?? Corner of "Bumf*&k and 'You've got a purdy mouth'."

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St. Jude Donor '06-'10, '13

Re: 81 dual exhaust (Dalannex)

Quote:

Yes, 1980 - 82 the crossmember only has 1 place to route exhaust, and that is on the passenger side. The only other solution is to cobble a pre-1980 crossmember into place like I did. They are not a direct bolt in.

Jun 28, 2003 | 01:02 AM

BSeery

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From: Exiled to Richmond, VA - Finally sold my house in Murfreesboro, TN ?? Corner of "Bumf*&k and 'You've got a purdy mouth'."

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Re: 81 dual exhaust (Glensgages)

Quote:

I was told that to provide more driver-side head room, driver-side seats are a bit 'lower', mandating all exhaust goes down passenger-side.Sounds plausible..... :confused:

No, they just changed to a MUCH lighter crossmember and only allowed one place to route the exhaust. Not much care by GM since they were only building 3 model years like this and couldn't do duals anyway.

The exhaust is actually pretty close to the transmission tunnel and almost against the trans on mine and does not go under the seat.

Jun 28, 2003 | 01:09 AM

Glensgages

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From: State of Confusion

Re: 81 dual exhaust (BSeery)

Quote:

Thanks, BSeery. I recently saw an '82 C.E. on a lift after getting true-duals (2.5", no cat OR mufflers for $150.00!!!). The owner told me of the 'low-seat' theory. On this car, it DID look as if driver's-side floor-pan was lower than passenger-side. I guess I 'bought' it....

Jun 28, 2003 | 03:30 AM

Hemmo

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From: Kirkkonummi

Re: 81 dual exhaust (BSeery)

Quote:

And No again, driver-side seat doesn't sit lower but the motor and bracket take more room than passenger-side so the floor pan is deeper and comes in way when you are installing duals. Don't know about crossmember since I don't have stock one.

I have duals installed and only problem is that driver-side pipe touches the pan. That I deal with little heat barrier installed between them, it also prevents pipe hitting the pan on idle as it's vibrating.

Jul 5, 2003 | 01:18 AM

vettesite

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From: Palatine IL

Re: 81 dual exhaust (Ben Taylor)

I have 2.5" true duals, no cats, H pipe, and headers on my 1980. No seat clearance issues. Just get a dual hole automatic frame cross member from a 1979 or older. It bolts on with some modification. You will also need the perch (mounting bracket) that the trans sits on that bolts to the cross member. I have a dual hole cross member (no perch) if you are interested, webmaster@vettesite.com

Here is a pic:

http://www.vettesite.com/1980vette.asp?mypage=exhaust

[Modified by vettesite, 12:22 AM 7/5/2003]