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TB bypass isn't worth it IMO, neither is removing the screen.
 
On MotorTrend channel/site the Engine Masters guys did dyno tests looking at heat and its effects. At the end of the day, on a big HP v8, the greatest impact was cold fuel. A hot intake manifold (heated air) made no difference. The air velocity is too great for the heat in the TB to make any difference.
Either cool the air charge (with an intercooler) or the fuel (which will result in a cooler fuel-air charge).
Also the gains were less than 10hp/tq (all pulls with ambient air)
Also cooling your fuel matters more for carbs or TBI injection than port injection...

Leave the TB coolant hoses in place, leave the wire mesh in place
 
On MotorTrend channel/site the Engine Masters guys did dyno tests looking at heat and its effects. At the end of the day, on a big HP v8, the greatest impact was cold fuel. A hot intake manifold (heated air) made no difference. The air velocity is too great for the heat in the TB to make any difference.
Either cool the air charge (with an intercooler) or the fuel (which will result in a cooler fuel-air charge).
Also the gains were less than 10hp/tq (all pulls with ambient air)
Also cooling your fuel matters more for carbs or TBI injection than port injection...

Leave the TB coolant hoses in place, leave the wire mesh in place
Yep, lots and LOTS of things from the days of Carbs, Vacuum advance ignition, Analog tuning and engine controls and all that doesn't transfer to modern engines, but, folks keep regurgitating it as fact.
 
kinda old thread but.... lol i had did this on my rsx type-s/r autocross car. for what it is it didnt make a difference but cooler fuel did. my question is how do u know it gets shut off after warm up.
 
I’m new here and live in Canada . I did this mod and bypassed the lines behind the supercharger on my O2 SC. On a hot day with the hood closed, according to the code reader, I managed to monitor the temperature at the IAC valve and it never got above 70°C so the idle wouldn’t come down, but no stumbling. With the hood open, The IAC valve never got above 56°C and went into multiple cylinder misfires along with high idle. Throttlebody is also bypassed - i’m going to order 10 feet of flexible 1/2 inch silicone coolant line and reconnect them as it’s also affecting fuel mileage. I’m finding that if you can’t stabilize the IAC valve temperature that it just won’t stabilize and cycles back-and-forth from bypassing to not bypassing air - From stumbling to running properly. Cheers
 
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