TIming tab for Summit 161350 balancer
Thread Starter
Racer
Joined: May 2011
Posts: 297
Likes: 3
From: Indianapolis
TIming tab for Summit 161350 balancer
I just bought a Summit #SUM-161350 balancer, and it did not come with a new timing tab. The note on the installation instructions states Chevy used two different TDC locations. Does anyone know if the stock timing tab will line up with the Summit 161350 balancer for a correct TDC indication? Engine is 1980 L-48.
Thread Starter
Racer
Joined: May 2011
Posts: 297
Likes: 3
From: Indianapolis
I noticed that too. To quote verbatim, their "dampers are designed to be used with the aftermarket 'bolt-on' style of timing tab." Does that mean the stock timing tab cannot be used?
The last time I bought a harmonic balancer (and it's been a few years) it came with a timing tab, and both the stock tab and the aftermarket tab had the same "TDC" 0° point. I could have used either to set the timing. So I am wondering of anyone who has used Summit's 161350 can confirm whether or not the stock tab can be used. I'll find out eventually when I install it, but I was hoping to get an answer in advance.
The last time I bought a harmonic balancer (and it's been a few years) it came with a timing tab, and both the stock tab and the aftermarket tab had the same "TDC" 0° point. I could have used either to set the timing. So I am wondering of anyone who has used Summit's 161350 can confirm whether or not the stock tab can be used. I'll find out eventually when I install it, but I was hoping to get an answer in advance.
Last edited by indydoug; Mar 28, 2012 at 11:55 AM.
Thread Starter
Racer
Joined: May 2011
Posts: 297
Likes: 3
From: Indianapolis
I just bought a Summit #SUM-161350 balancer, and it did not come with a new timing tab. The note on the installation instructions states Chevy used two different TDC locations. Does anyone know if the stock timing tab will line up with the Summit 161350 balancer for a correct TDC indication? Engine is 1980 L-48.
Racer
Joined: Nov 2011
Posts: 319
Likes: 12
From: South Chase WI
Very interesting. When I try to shoot the light on my 1981, the balancer marks show up in the 12 o'clock range, not the 2 o'clock range. I thought my balancer had slipped, maybe it's just the wrong / a different one.......
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If your timing had been set properly before the balancer change...and the distributor has NOT been moved, then you need to verify your engine's TDC location [mechanically] before you go any further. The mark on that balancer may not be in the correct location to use with the timing tab that is now on the car.
{You did remove/plug the vacuum advance line to the dist. advance can, didn't you?}
{You did remove/plug the vacuum advance line to the dist. advance can, didn't you?}
Racer
Joined: Dec 2007
Posts: 341
Likes: 29
From: vancouver washington
Just for referance, I bought the summit balancer only the larger 8" model. The timing tab for the old balancer (also 8") was dead on TDC. The new summit was off TDC by almost 1/2 inch. This was checked with the cylinder head off and a dial indicator to find tdc.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If you are not looking for exact precision, you can take the #1 spark plug out, bring the piston up just short of the TDC position, stick a large plastic drinking straw into the spark plug hole and slowly rotate the engine till the straw just stops further movement. That'll be within a degree or two.
If you have rebuilt the engine with a close-tolerance valve train, you need to check it [properly] with a timing stop tool.
If you have rebuilt the engine with a close-tolerance valve train, you need to check it [properly] with a timing stop tool.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
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
Racer
Joined: Nov 2011
Posts: 319
Likes: 12
From: South Chase WI
If your timing had been set properly before the balancer change...and the distributor has NOT been moved, then you need to verify your engine's TDC location [mechanically] before you go any further. The mark on that balancer may not be in the correct location to use with the timing tab that is now on the car.
{You did remove/plug the vacuum advance line to the dist. advance can, didn't you?}
{You did remove/plug the vacuum advance line to the dist. advance can, didn't you?}
No, these HEI's are not vac advance......you unplug the computer to set base timing, then when done plug it back in to allow the ecm to set the advance curve.
