Johnny Blaze

iTrader: (15)

When gathering parts for my build, I went with a 6 1/4" balancer. Jegs listed it as the one for the 1 piece rear main engines.

Now I can not find a timing tab that will work, the all list them for 6 3/4" or bigger.

Anyone see any issues with using one for a 6 3/4" balancer?

sofakingdom

iTrader: (1)

The 6¾"damper usually has the tab in the center of the timing cover.

I don't know offhand of any tabs that are long enough to reach way over there.

Thing to do would probably be to use whatever tab you feel like; and when you get to the point in building the motor where you can absolutely positively unmistakably without doubt or uncertainty unambiguously measure accurately where #1 TDC is, make a mark on it to line up with your tab.

Orr89RocZ

iTrader: (20)

I ran a 6" romac with stock L98 timing cover. Guess it depends where timing marks are set on the balancer? Mine had 360 deg marks. Tdc matched 0 on balancer with l98 cover

Johnny Blaze

iTrader: (15)

Shortblock is assembled.

Timing mark on balancer is inline with keyway on crank.

Installed a tab for a 6.75 balancer, and it's way off. At tdc the mark aligns with 8 degrees advanced.

Other option looks to be a timing pointer for a 6.25 which I have seen, and timing tape on the balancer.

How long will timing tape last on a street car?

Johnny Blaze

iTrader: (15)

Shortblock is assembled.

Timing mark on balancer is inline with keyway on crank.

Installed a tab for a 6.75 balancer, and it's way off. At tdc the mark aligns with 8 degrees atdc.

Other option looks to be a timing pointer for a 6.25 which I have seen, and timing tape on the balancer.

How long will timing tape last on a street car?

redneckjoe

small chevy's only use 2 different timing tabs,... 12 o'clock & 2 o'clock. sofa has a good point, verify TDC. make your own marks. its just a number, set it and test it,...write down what works best for you. i personally dont see the NEED for timing tape, etc. make your own marks with a sharpie on the balancer.
heres a 6 3/4" balancer cover. 35 degrees is roughly 2" from 0. should get ya in the ballpark.

Damon

That's not entirely true. GM put the timing marks in a SLIGHTLY different position prior to.......mmmmm...... about 1967, if I recall correctly.

MODERN balancers used only 2 positions that I am aware of- 13* offset (from crank keyway) or 45* offset. And the sizes were almost always either 6-3/4" (sometimes called 7") or 8". Most of the 8" balancers used the 13* offset, but not all. The 6-3/4" balancers were a mixed bag but certainly a lot more of them used the 45* offset than did the 8" variety.

Johnny Blaze

iTrader: (15)

Sure I can make some marks on the balancer, but I still need a tab or a pointer on the engine to align the marks on the balancer with.

That's the issue.

Tdc has been verified as mentioned.

With number one at tdc the 0 mark on the balancer aligns with the last mark on the current tab.
Sure I could go with that, and hope to remember it's not actually 8 degrees advanced, but what if someone else comes along and has to time it?
If they were to set it at 8 degrees before tdc according to the tab, it would actually be 16 degrees btdc.

Like I said I'll probably just get a pointer for the 6.25 balancer, and throw a $3 timing tape on it. I guess I could save $3 and get the tape measure out and a marker and spend some time drawing on the balancer, but I don't see that as worthwhile, when the tape already has all the numbers laid out nice and neat.

Johnny Blaze

iTrader: (15)

This is at tdc.

Orr89RocZ

iTrader: (20)

Make the 8 a 0 and go from there.