Stock TB Size?
Thread Starter
Melting Slicks
Joined: Mar 2001
Posts: 2,978
Likes: 280
From: Tulsa OK
Stock TB Size?
Can someone confirm for me that our stock TB is 78mm? Also, does anyone know what size TB the 5.3L truck engine uses? I'm trying to get some idle and start up issues sorted out with my tuning. TSP dyno tuned the car, but did not have a chance to work out all of the cold start and idle issues. My mechanic does tuning and thinks that part of the problem may be that the tune wasn't properly adjusted for the 90mm TB. Thanks!
Drifting
Joined: Apr 2004
Posts: 1,530
Likes: 250
From: CT
Stock C5 TB for all years is 75 mm. There are a few aftermarket TBs that are slightly larger and fit the LS1 or LS6 intake manifold neck, max that will fit is 80 mm. For example, the Callaway billet TB is 78 mm, 3 mm larger than stock. Hope this helps.
