injecting pre turbo with twin turbo
 

I know it has been been done before, but the intakes on my car are somewhat long and I'm worried about the the turbos not getting equal amount of water and meth through them making the loads uneven. I want to place the nozzle at the filter just before the intakes Y off and go to each turbo by themselves.

I would rather not use 2 different nozzles to inject. I should add that I'm using a mechanical setup similar to how dudeman did his way back and is still currently doing.


Anyone here do something similar? I don't forsee it being a problem, but sometimes I am overly cautious. it's easier to ask here rather than destroy parts and spend time and money fabricating something for no reason if these could be resolved by a simple question on here.

Twin Turbo
 

The main problem with twins is if they are still sequential, if an FD. The secondary turbo would be sprayed and would not be spooling with low boost. Not good. I have solved this problem and will be posting the way I solved the problem after my installation and testing is complete using a small ultra low vacuum switch, a relay, and a solenoid that solves the problem on the secondary.

If you are still running seq the fix is easy... two different nozzles one for each, both have there own solenoid inline to stop water flow...


Primary turbo injection is set off of boost switch, which activities water flow


Secondary turbo, use the Charge control solenoid signal to activate the soleniod for water flow to the secondary turbo...

Simple, only thing needed is basicly to pre-turbo kits, funning off two different signals to activate. Both getting fluid from one tank....


J.

That works well too. The only small problem I see is the secondary turbo will be sprayed and may not yet up to full spool. Using a vacuum switch, it directly measures the turbo's vacuum in the intake side or true spool point at which the turbo is working. The secondary on my setup begins to supply boost at 0.015 inHg and tops out at 0.063 inHg measured on the intake pipe. My vacuum switch is set for to trip the solenoid at .02 inHg and will close the solenoid at less vacuum. If you were to use the charge control and were at low rpm and floor it, you would be spraying the secondary and producing no true boost yet (not spooling well with low exhaust flow) and would be flooding the secondary with water. Also, if the turbo is being hit with spray and is not up to a decent spool point, you would be effectively slightly hampering it from gaining rpm. My way, until there is any true decent spool level and true boost, no water. You are directly measuring the secondary's spool level at producing true boost. The secondary has to be truly working to be sprayed. Just my thoughts.

Edit:

Need to correct my info first


J.

Instead of vacuum one could also measure pressure just after the compressor of th 2nd turbo. if its prespooling the bov like valve will circulate air back to the intake causing you possible to falsely see a small vacuum signal upstream its compressor without it boosting properly.

You could use a pressure switch on the output of the secondary turbo, but you will get no boost until the bypass valve that vents the pressure closes. Then you will get all the pressure at once to throw a pressure switch. This is not ideal since the turbo is near full spool at that point. This is opposite to using the charge control signal- no significant true spool yet or similar to using the Y-pipe signal for combining the two turbo- already spooled and late. Using the intake side vacuum, you can start your spraying as the secondary turbo is starting to spool. Much better. Also, the bypass valve on the secondary side dumps into the stock airbox and would do nothing as far as showing false vacuum on the secondary turbo true intake. I have aftermarket aluminum intakes for each turbo and the vacuum switch is tapped into this intake pipe.

I have attached a manometer graph from my secondary turbo intake pipe. It shows the vacuum that is created in the pipe when I floor my car around 20 mph in 2nd gear. This was reproducible each and every time. As I let off the gas, the vacuum disappears in split second and the solenoid closes immediately. I set my micro vacuum switch to trip at .022 inHg, which throws a fast relay, which opens the solenoid to the secondary turbo sprayer if total boost at the intake manifold(from primary too) is above 5 psi, already tripping my water-meth controller. Works like a charm.:nod: