On the drivers side of the block of the L98 pretty much in the center there's a plug there in the middle of nowhere....anyone know what that is for?
I'm trying to find possible places for my autometer coolant temp. sensor....so I don't have to use a T-connector on the driver's side head with the existing sensor.

I can snap a pic of it if needed....

Thanks,
- Joel

 

By any chance is the knock sensor in the corresponding hole on the passenger side?

If so, that's the water jacket drain that's been in SBC's since 1955. It's a poor place to put a temp sensor since that's one of the coolest parts of the cooling system. In a head or intake water passage is much better.

 

Yeah...the knock sensor is in the coor. pass. side hole.
The coolant drain...thanks man....I've been wondering what that was for a while......
You're right....that would be a bad place for the sensor.....looks like I'll just pickup a T and throw it in the drivers side head along with the stock sensor. Thanks for the info! I'm gonna be dangerous soon with all the knowledge I've gained here LOL!

- Joel

 

In addition to being a cold spot, it's a poor position for a temperature sensor because most debris in the cooling system tends to accumulate there. This tends to insulate the sensor from accurate readings.

You can also drill/tap another hole in the opposite end of the head for an additional sensor, or drill/tap the coolant crossover of the intake.