Reply To: rochester r/rc, jetfire carb pics

[JimNoel]

Yes, the large brass lines are for engine coolant to run through the throttle body. The coolant also runs through the compressor housing side of the turbo unit. The factory stock turbo engine has 10.25 to 1 compression ratio and needed a method to reduce pre-ignition caused by the piston tops and heads getting too hot under boost. Modern day turbo cars can accomplish this by retarding the spark with a computer controlled distributor. For the 60’s Jetfire cars this was accomplished by the water/methanol injection technique. You will need to address this issue with your modifications to a Jetfire engine to keep from burning holes in the piston tops. To understand the function of the safety systems put on by Oldsmobile, see this article on this website: http://oldsjetfire.com/turbo-system-safety-checks/