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 Manifolds and Exhaust

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Deadmanonduty
rjathon
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rjathon

rjathon


Posts : 268
Join date : 2014-10-28
Location : Sun City Center, FL

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PostSubject: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeWed Jul 15, 2015 7:19 pm

I think that it is time to liven up an old topic from a different perspective.

My stock cast iron manifolds will be up to speed next week. A cheap Dorman manifold on the passenger side and a new fel-pro gasket on the driver side, plus some new bolts and retorquing, and life is good....except that holes are lurking in the mufflers. My guess is that when they pass 20 years old coming up soon that they will need replaced.

I'm wondering if pipes will need replacing also.

My desires are:

1) quiet. The less sound the better.

2) SS for longevity

3) efficiency below 2000 rpm. I watch my rpms via the HVAC and they rarely surpass 2000. Occasionally while on the interstate I might briefly hit 2500 rpm while passing uphill.

4) I could care less about wot, peak hp, burning rubber, etc. what I do like is being able to stay in TC lock up at 70 mph while going uphil and not having to downshift too much.

I marvel at how my 20 year old beauty can cruise the interstate doing 70 mph @1500 rpm while my neighbors Lexus and my sons Suburus pull ~3000 rpm to accomplish the same feat while enduring much more noise and road bounce and burning more fuel.

So, from this delightful perspective from a "soft foot" what exhaust recommendations do you have?

Thank You


Last edited by rjathon on Wed Jul 15, 2015 7:25 pm; edited 1 time in total (Reason for editing : Typos)
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Deadmanonduty




Posts : 539
Join date : 2011-08-30
Location : Green Bay, WI

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeWed Jul 15, 2015 7:25 pm

stock. Theres no reason to upgrade as you never let yours breathe! The stock exhaust can easily handle that motor just above idle.
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phantom 309

phantom 309


Posts : 5848
Join date : 2008-12-28
Age : 114

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeWed Jul 15, 2015 8:58 pm

L99 option would be good for you,.
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rjathon

rjathon


Posts : 268
Join date : 2014-10-28
Location : Sun City Center, FL

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeWed Jul 15, 2015 9:13 pm

Thank you
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Andebe

Andebe


Posts : 3323
Join date : 2013-02-20
Age : 54
Location : Centerville, IN

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeThu Jul 16, 2015 10:43 am

Ive never driven the L99...Is it better than stock tbi?
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Fred Kiehl

Fred Kiehl


Posts : 7146
Join date : 2009-11-13
Age : 75
Location : Largo, FL 33774

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeFri Jul 17, 2015 9:23 am

Andebe wrote:
Ive never driven the L99...Is it better than stock tbi?

The L99 may have slightly more HP, but the maintenance is much higher than the LO3/5. If you are thinking about an engine swap, go for a small LS series engine. You will get the gas mileage and substantially more HP than either of the others.
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Andebe

Andebe


Posts : 3323
Join date : 2013-02-20
Age : 54
Location : Centerville, IN

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeFri Jul 17, 2015 10:25 am

Fred Kiehl wrote:
Andebe wrote:
Ive never driven the L99...Is it better than stock tbi?

The L99 may have slightly more HP, but the maintenance is much higher than the LO3/5. If you are thinking about an engine swap, go for a small LS series engine. You will get the gas mileage and substantially more HP than either of the others.
Noooooooooo,just curious about the motor. Thanks for 411.
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Deadmanonduty




Posts : 539
Join date : 2011-08-30
Location : Green Bay, WI

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeFri Jul 17, 2015 6:25 pm

The LS doesn't make tractor torque down low like the poster likes!
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phantom 309

phantom 309


Posts : 5848
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Age : 114

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeFri Jul 17, 2015 6:54 pm

I,ve had 2 L99 cars,. and they are great motors,.and not as slow as folks that don't have them think,..

I bought a 1995 1A2 wagon,. the owner had put an L99 exhaust on it,.

it was quiet and ran fine,..
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rjathon

rjathon


Posts : 268
Join date : 2014-10-28
Location : Sun City Center, FL

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeThu Aug 06, 2015 6:24 am

I keep having to re-torque the exhaust manifold bolts to keep the dreaded "lean bank1" and "lean bank 2" codes away. Any suggestions? The bolts are all new.

Also, as these cars are nearly 20 years old are we still required to have the catylitic converters installed?

Thanks,
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Fred Kiehl

Fred Kiehl


Posts : 7146
Join date : 2009-11-13
Age : 75
Location : Largo, FL 33774

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeThu Aug 06, 2015 8:40 am

The cat issue depends where you are. If you have sniff tests, you probably need them. I do not know if the laws where you are delineate a date for noncompliance.

You could put some thread locker on the bolts, or cross drill the heads, and safety wire them. The thread locker may not work correctly because of the heat.

The bolts came from the factory with a thick "washer" under them to allow for expansion and contraction. If you do not have the OEM style washers under them the heat/cool cycles may be loosening the bolts.

The manifolds came from the factory without gaskets between the manifold and head, and depending on what type of gasket you have, the gasket may be crushing a little more with each heat/cool cycle.
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Deadmanonduty




Posts : 539
Join date : 2011-08-30
Location : Green Bay, WI

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeThu Aug 06, 2015 9:06 am

I believe the law is that any car that came with a cat needs to keep it.
From what I have heard its $1,000 fine for not having them on and $10,000 fine to shop that removes them.

Rules are made for breaking!
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MalibuSSwagon




Posts : 580
Join date : 2014-01-12
Location : NH

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PostSubject: Re: Manifolds and Exhaust   Manifolds and Exhaust Icon_minitimeThu Aug 06, 2015 9:34 am

Just check your state laws. Here most emissions equipment must remain in place for the visual inspection. No sniffer test or anything. But it depends on your local laws
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