Dual A/I on both front and rear rotor intake runner
 

Is imposdible to find race gas in my country, so I use A/I injecton to lower my EGT, but my rear rotor always seen to run higher then front, this season update to xcessive lower intake, was thinking with even runner can equal egt, but rear egt still a bit, so before my last race , want to put dual ai to see if this help out on egt or not

I like it! I'm interested to see pics of the manifold with the nozzles mounted in it as well as hear if the results show that you actually lower the EGT with the equal distribution, I may be doing something similar in the near future.

Skeese

Hey diyman, love your YouTube series! Are you using the factory Double Throttle plate in this intake manifold setup for your race car? If so, this MAY not work until after a certain RPM/Load threshold since the secondaries are closed off. Love it. This is a damn good place for AI!

This link below is more on the FD intake manifold project I've been doing. Looks like your double throttle plate is removed, but just making sure to post this for those who either haven't removed it or don't realize that this AI system wouldn't work until over that threshold point (since no airflow is going to the secondaries yet).

RGHTBrainDesign - Rotary Engine Development Projects

Thanks, never know I bump into one of my youtube fellower ;)
U get a point on secondary throttle plate ~ but this should affect me less, because when u see,my newest video , I use dual cam one is footcam, I setup my car with tons of traction, so most of time I am on WOT, and high EGT on rear only accure at some where is high load abd rpm on 3th gear, it happend on turn 3 at last corner toward end , right before brake point
Btw Very cool project u have !!!



Thanks, when resource is not enought, u should be creative !! When I tune my car on dyno, I switch off A/I only turn it on at track
Of course car will run pretty rich, from my wide band it show A/F was lower 10.8 front 11.3 , most people ask me how can I run factory twin turbo in one hour endurance without issue, mabe this is why

To the OP, are you sure it's not the EGT probes themselves? This problem came up before and by switching the EGTs and thermocouple amplifier channels, it was verified that the two probes were actually reading differently when the owner assumed they were working fine. I would eliminate this first, and then see whether there is an underlying tuning issue for the disparity between front and rear EGT (eg looking at fuel trim between F and R).

See here: Exhaust gas temp difference front/rear rotor - how to tune? - AusRotary

Also, intake runners are, at most, half the equation. What about exhaust manifold design and turbo position? It is actually not unusual for rear to be hotter than the front. I don't know why but it comes up fairly often - I suspect closer proximity of turbo and wastegate components has something to do with it, but I'm sure other more knowledgeable people will have their own theory. It's a question of degree - how far apart are your front vs rear temperatures?

This was already addressed in your other thread, but the above post needs correction here. The Double Throttle plate will not affect secondary inlet tract airflow unless the coolant temperature is under around 70'C. Otherwise, they are fully open. In a normal OE FD throttle body, the secondary throttle plates will be closed when the throttle position is below a certain angle (around 15% I think but I would need to test). They then open progressively. Even under very low TPS values, there will be some air flow through the secondaries, so I dare say this will not affect water injection in the secondary inlet tract location (and in any event, there will be engine vacuum pulling water through even when the secondary throttle plates are closed).

Finish the dual A/I set up

Thanks for input
With stock style twin , get a lot of high back pressure and poor turbo manifold design
This could most likely be why I have such high EGT !!!

100% agree. The stock twin cast manifold is essentially one big thermal choke brick that causes high preturbine backpressure. The lack of flow with those temps going in doesn't dissapate the heat and presto... high egts.

Skeese

Any results or feedback after implementing direct injection? Curious to know how things turned out. Thnx

Had forgotten about this thread! Also in for results....