Timing belt replacement error?

[90 Gen2]

On our 3SFE-equipped 90, the timing belt was recently replaced.
Less than 300 miles later, there is a bit of an oil leak out the front cover somewhere (great thanks.) Also, when setting the ignition timing, 10 degrees BTDC used to be about center of the distributor's slots. Now, I am able to set the timing advanced quite close to the end of the slots without pinging (except short light pinging occasionally when applying a lot of throttle right off idle in Drive from a sull stop,) to the tune of an indicated 26 degrees BTDC on the "dial back" digital timing light.
Did the shop not only fail to replace and/or not disturb oil seals in front, but also manage to install the cam belt incorrectly timed? It seems that maybe if the cam(s) were accidentally retarded a tooth, that advancing the distributor an indicated extreme amount would actually be close to intended position. But not really? If the reference mark on the pulley is attached to the bottom end of the motor, shouldn't the position of the distributor rotor relative to the piston positions remain the same despite whatever the heck they did to the cams?

Is it normal to be able to advance the timing so far without pinging?
At the factory recommended setting of 10 degrees BTDC (at around 800 rpm), the car drives like SUCH a dog it drives me nuts. It takes about 17 degrees just to be tolerable, and like I said, the 24-26 degree range is so much better.

Any experiences to share?
Thanks!

[Tom 2000]

When you set the ignition timing, I assume you used a jumper wire to bridge terminals T and E1 on the check connector before you set it.

[90 Gen2]

jumper wire between those 2 terminals, check.
idles speeds up about 30-60 rpm when jumper is later removed...

[88 LE]

Originally Posted by 90 Gen2

If the reference mark on the pulley is attached to the bottom end of the motor, shouldn't the position of the distributor rotor relative to the piston positions remain the same despite whatever the heck they did to the cams?

No.

The intake cam drives the distributor. So if the timing on the cams is off, your ignition timing is off too.

Is it normal to be able to advance the timing so far without pinging?

No.

At the factory recommended setting of 10 degrees BTDC (at around 800 rpm), the car drives like SUCH a dog it drives me nuts. It takes about 17 degrees just to be tolerable, and like I said, the 24-26 degree range is so much better.

Sounds like the camshafts are retarded (no pun intended) due to improper timing belt installation.

[90 Gen2]

Thanks, that does seem to make sense...
It seems like if the distributor/cams have been retarded, what, 14 or so crankshaft pulley degrees, that's....7 camshaft degrees? Seems like I would notice a big change in the torque curve with that setup....would that be a shift toward higher rpm with a sacrifice down low? Or probably more likely just a big loss down low and slightly less roll off at mid-high range?

that just seems like a big error that should be more noticeable than it is....

[88 LE]

Originally Posted by 90 Gen2

Thanks, that does seem to make sense...
It seems like if the distributor/cams have been retarded, what, 14 or so crankshaft pulley degrees, that's....7 camshaft degrees?

Depends how far off the cams are in relation to the crank. I don't have exact numbers, but its off.

You can check it out yourself by removing the upper timing belt cover. Turn the crank pulley clockwise till the notch on it lines up with the "0" mark on lower timing belt cover. You might have to rotate the crank 2 full turns (TDC to TDC) depending on the position of the cams.

When #1 is at TDC (notch on crank pulley lined up to "0" mark). The cams should also be at TDC (ie: hole in camgear lined up with the notch on the bearing cap). Bearing cap is right behind the camgear.


Pic of camgear from 3S-FE:

[90 Gen2]

Interestingly, there are 48 teeth on that cam gear.
360 degrees divided by 48 is 7.5 degrees.
Camshaft rotates at 1/2 crankshaft speed.
I'm 14-16 degrees "advanced" in ignition setting to achieve decent performance.
15 degrees crankshaft advance is 7.5 degrees cam advance, or exactly one tooth.
Seems like a lot of circumstantial evidence pointing toward the belt being installed a tooth off!
I'll check it out.
Thanks for the picture of the cam gear and the advice!