What's the stock Z28 exhaust size? Is it 2.5" cat-to-muffler with 2.25" outlets?

 

yes

 

cat to the muffler is 2.75.

 

Yes


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2002 Camaro Z/28 LS1 A4 (2.73's)
Sunset Orange Metallic
Fernco, SLP Airlid, K&N Filter
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1995 Ford Aspire M5
!Torque & !Power

 

No. See post on Z-28 vs. SS Exhaust differences. From the y-pipe to the muffler is 2.75. The tail pipes come out to much less than 2.25, probably actually 2.0.

Dave

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Dave "Vegatex" English
<'02 Sebring Silver/Ebony Leather Z-28 A4; T-tops, 3.23 gears, ASR.
Mods: Spectacle SFC's/STB, FIPK, de-screened MAF, red calipers, leather shift boot.
96 LT1-powered '76 Vega Wagon, Howell Engine Developments Computer and Harness, Sanderson CC-13HO headers, Be Cool aluminum rad w/dual 11" SPALS, custom cold air induction, 700r4, Modified 7.5" 10 bolt w/Torsen rear diff, 28-spline Moser Custom Alloy axles, 3.42 rear, '98 Camaro rear disks, cross-drilled and slotted S-10 front disks. 2800 pounds of fuel-injected Whoop-***!>
http://h-body.org/people/projects/building_lt1/index.html

 

Yep, it's 2.75", not 2.5".


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1997 Bright Red Z28
A4, 3.23's, K&N FIPK, FLP Headers, Flowmaster, Cutout
My Z28