Rb30 turbo carbon canister help

Hey guys, I’m currently finishing “a half done” vl turbo wagon build that was someone else’s forgotten project before it came into my possession. Among many other short comings I’ve come across on my path to restore this thing to a properly functional vehicle good enough to be daily driven, im try to restore most of the emission control systems.

now the question I have is: how do I go about reinstalling the carbon canister system from what was originally a NA rb30 to a turbo rb30?

From what I can see, like most of the engine it’s vacuum operated, so how does the introduction of a turbo affect this? Does any body know if the turbo motors had a different solution?

or is there even an alternate solution to dealing with the fuel vapours without just venting them to air and stinking up the shed?

thanks guys

Hi David,

Generally most carbon canisters are controlled via a solenoid valve, this is opened at idle or when the car is first start to draw in the hydrocarbons captured from the fuel tank.

This works for a NA or turbo car as boost is not created at these conditions. Then when under load/boost the valve closes.

From memory (has been many years since I have played with these) The carbon canister only operates at idle.

I’ve had a bit better of a look and it looks like it’s operated by a vacuum controlled diaphragm at the top like in the picture.

Since I’ve decided to run an electric vac pump to supply my booster and heater controls as it’s more reliable and less bulky then the old school vacuum resivuior ball ran on the turbo rb30’s, how will this affect the operation, I assume it will mean it’s now constantly open to let vapours into the intake manifold, so again because I’ve boosted the car I’m assuming I should use a one way check valve between the manifold and the canister? So In theory it will only be pulling in vapour at low rpm/idle. Is this correct?

and what considerations should I make regarding my tune for this. As it will be variable depending on fuel tank level and atmospheric temp. Will feedback from an afr sensor be all I need to compensate?

thanks for your help

I am unsure how the older cars ran the original carbon canister setup, most modern cars run via a solenoid which will only operate when cold started or idle.

However, I would tend to agree that running it with a one way valve in line and plumbed to the intake should work just fine. Then it will work at idle and light throttle. Assuming there must be some form of vacuum control in the canister or breather in the tank so you don't vacuum the tank?

Tune wise, if setup correctly, the tiny amount of hydrocarbons drawn in from this will make very little/if any change to the tune. We see cars remove them often and no change to the tune has been required.

sounds good, yeah there is a vacuum port on the top which looks like it’s a diaphragm, so I’ll hook that to the electric vac system and then the purge port will be open at all times but only be used at idle and light throttle because of the one way valve and boost pressure.

thankyou