91 ZR1 Aqua Metallic

[TealZR1]

The prior owner bypassed the 2 upper front plenum coolant hoses on each side and took a longer hose and wrapped it around and under the air opening of the plenum. He said it helped cooling.
To go back to the original setup, is it possible to just reconnect two shorter hoses on the plenum where the exposed 2 "fitment" openings are? Not sure if I said that correctly but any help is appreciated. Thanks

[Paul Workman]

Originally Posted by TealZR1

The prior owner bypassed the 2 upper front plenum coolant hoses on each side and took a longer hose and wrapped it around and under the air opening of the plenum. He said it helped cooling.
To go back to the original setup, is it possible to just reconnect two shorter hoses on the plenum where the exposed 2 "fitment" openings are? Not sure if I said that correctly but any help is appreciated. Thanks

The TB has been bypassed via the tube passing under the plenum; sounds like the bypass technique Marc Haibeck employes.

Reverting it back is simply reinstalling the hoses from the right and left IH to the respective ports on the TB.

Resons for bypassing the TB in the first place is

-to avoid heating induction air to optimize intake air density (horsepower!)
-reduce the temperature of the plenum...which serves as the heat sink for the precious DIS module; by FAR the best reason of all (in my mind, anyway!)

The reason for reverting back to stock-

-to protect against TB freeze-up in near or sub-freezing driving
-to score higher in NCRS judging events.

For the reason of reducing the DIS module HEAT is really worth considering before reverting the bypass.

Just sayin!

[conesare2seconds]

Paul covered the bases very well. Just wanted to add one more possible consideration for leaving the TB bypassed is to conserve the finish on the throttle body, which is supposed to be adversely affected by the stock setup.

[TealZR1]

Thanks Paul W and Con2. Put it back to the original setup and all is well! Have a great weekend

[TealZR1]

Originally Posted by Paul Workman

The TB has been bypassed via the tube passing under the plenum; sounds like the bypass technique Marc Haibeck employes.

Reverting it back is simply reinstalling the hoses from the right and left IH to the respective ports on the TB.

Resons for bypassing the TB in the first place is

-to avoid heating induction air to optimize intake air density (horsepower!)
-reduce the temperature of the plenum...which serves as the heat sink for the precious DIS module; by FAR the best reason of all (in my mind, anyway!)

The reason for reverting back to stock-

-to protect against TB freeze-up in near or sub-freezing driving
-to score higher in NCRS judging events.

For the reason of reducing the DIS module HEAT is really worth considering before reverting the bypass.

Just sayin!

Paul, I may have spoke too soon on TB connection back stock. I short time later after doing this, I sprang a good size oil leak at the oil pan. Any connection to this? Or just a coincidence and now I have another problem. Thanks in advance if you have any input.

[We Gone]

Another good reason to by-pass is to eliminate the corrosion that occurs to the top of the throttle body around the plate on top. Your oil leak could be front oil pan bolts, oil cooler hoses or one of the oil sending units on housing the oil cooler hoses connect to.

[TealZR1]

Thanks We Gone, after I park the car the puddle of oil, which just started two days ago without even a drip, ends up with about a 1' x 3" puddle. A substantial amount only after a short drive. Which gets me to think it may be more than just tightening bolts or a bad gasket. Possibly more substantial like you were thinking, an oil cooler hose or oil sending unit. Thanks for your help