1.6 rockers
Thread Starter
Instructor
Joined: Jan 2003
Posts: 241
Likes: 0
From: south boston va
1.6 rockers
96 lt1 just upgraded my rockers, now car stumbles at cruzin speed, changed the feul filter. need some help with this problem, car still ran 13.06 @ 105 mph 11/16/03. mods prog III-- cold air-- air foil thanks for any advise :mad
Instructor
Joined: Oct 2003
Posts: 147
Likes: 0
From: Holbrook NY
Re: 1.6 rockers (STL94LT1)
It is unlikely that the rockers are adjusted improperly, if the only trouble is a stumble, as you describe.
First most likely are things you disturbed - the TPS and TV adjustments may have been disturbed. For sure the ignition wires were all removed. Perhaps a frayed wire is touching something. A vacuum leak may have been introduced.
Next most likely are the classics. Stumble is caused by a loss of fuel or a loss of spark. Is the FP pressure rock solid? How about ignition?
Very loose rockers clack at idle. Tight ones never seal, rob HP everywhere, and burn valves. It is not directly related to new your rocker arms, but you may have unmasked or even caused a new problem.
George
First most likely are things you disturbed - the TPS and TV adjustments may have been disturbed. For sure the ignition wires were all removed. Perhaps a frayed wire is touching something. A vacuum leak may have been introduced.
Next most likely are the classics. Stumble is caused by a loss of fuel or a loss of spark. Is the FP pressure rock solid? How about ignition?
Very loose rockers clack at idle. Tight ones never seal, rob HP everywhere, and burn valves. It is not directly related to new your rocker arms, but you may have unmasked or even caused a new problem.
George
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: 1.6 rockers (George West)
GM 1.6 rockers are non-adjustable, fyi. You tighten them down to 18ft/lbs (if memory serves me correctly), and just let them go like that. They are kind of loud... but that's normal.
Le Mans Master
Joined: Oct 1999
Posts: 9,713
Likes: 3
From: Sachse Texas
Cruise-In I Veteran
Cruise-In II Veteran
Re: 1.6 rockers (Curveit)
Curtis, that is only the stock LT4 rockers and stock LT4 studs. The other GMPP 1.6 rockers are adjustable 3/8" rockers as are all aftermarket ones.
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: 1.6 rockers (Vette92)
Curtis, that is only the stock LT4 rockers and stock LT4 studs. The other GMPP 1.6 rockers are adjustable 3/8" rockers as are all aftermarket ones.
edit: oops, ok i didn't say stock ones. Thought i did. It didn't say which ones you installed ... meant to say stock.
[Modified by GlockLT4, 8:25 PM 11/17/2003]
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,008
From: Texas
Re: 1.6 rockers (1320dance)
The TPS is not adjustable on a '96, so disregard that advice given previously.
You mention you changed to 1.6 rockers. Typically, at a minimum, when people make that swap they change to LT4 valve springs. If you didn't swap springs, did you verify that the LT1 valve springs can handle the added lift? Could be coil bind.
Got all the vacuum lines reconnected properly? Double checked all the electrical connectors? PCV valve functioning?
If it didn't do it before the swap and it does it now, you've pretty well narrowed it down...you need to recheck everything you took apart and reassembled.
You mention you changed to 1.6 rockers. Typically, at a minimum, when people make that swap they change to LT4 valve springs. If you didn't swap springs, did you verify that the LT1 valve springs can handle the added lift? Could be coil bind.
Got all the vacuum lines reconnected properly? Double checked all the electrical connectors? PCV valve functioning?
If it didn't do it before the swap and it does it now, you've pretty well narrowed it down...you need to recheck everything you took apart and reassembled.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer