Published 2022
Cam shaft and crank sprockets: SAE vs. Metric
There has been much discussion regarding the cam shaft sprocket differences but there is an additional caveat to all of this. The crank shaft sprockets are different as well. One of the most important things to consider when rebuilding an R16 engine is not to mix and match SAE and Metric sprockets. A metric cam uses a 10mm bolt to fasten the sprocket while a SAE cam uses a 3/8" bolt. As a Go-No Go use a 10mm x 1.5 bolt to ensure you have a Metric cam. Using SAE cam shaft sprocket and a Metric crank shaft sprocket is a bad thing as it will throw your timing off. Or the other way around-Metric cam and SAE crank. Your engine will never run due to the timing being off by 3 to 6 degrees. So, the moral to this entire story is to not mix and match sprockets. If you use a Metric cam use a Metric crank sprocket. If you use an SAE cam use SAE sprocket on the crank. I have heard from a good source a vendor is going to make matched sets with an S mark for SAE and an M mark for Metric.
I am certain there are many 1600's that have been rebuilt with the incorrect sprockets making them impossible to tune for peak performance. No easy way to check this short of pulling the engine, removing the front timing cover and checking the alignment of the timing marks. I suppose you could try it in the car but my preference would be to pull the motor and put it on a stand.
The timing chains are all the same. No difference what so ever.
Hope this helps some out there.