73-87chevytrucks.com
General Site Info => General Discussion => Topic started by: BBM3 on August 20, 2015, 12:05:15 am
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https://www.youtube.com/watch?v=qTPdBDVN7lg (https://www.youtube.com/watch?v=qTPdBDVN7lg)
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Well that's pretty, sounds like a real screamer.
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The same principle as a mid '80's / early '90's daily driver TBI but flowing huge amounts of fuel.
It is so archaic compared to todays F1 technology yet still looks amazing.
And that dyno run replicating a track lap is cool too.
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Yea it's definitely old school. My 73 runs an 89 TBI system. Works great, reliable, just like GM built it. My 91 camaro that I used to have was MPI, Multi-Port Inject. That basic design has remained the same for years and years. It continued into the LS engines and has proven itself for over 20 years. Now, each injector is inside the cylinder with the spark plug because most new engines now are direct injection. That in it self is also reliable and powerful and fuel efficient.
Those old TBI injectors were pretty powerful, each had to basically supply enough fuel for 4 cylinders. That's alot of fuel to have to spit out continuously. Today's injectors are even more powerful, the fuel systems on the new GM trucks and suvs are running around 1,000 psi fuel pressure. 1,000 PSI!!
Modern fuel injection really is a marvel.
My friend has a brand new Nitro bass boat. It has a Mercury 225 2 stroke V6 and the oil and fuel are both direct injected into the cylinders. That thing is blast to take out fishing.
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So, as long as the injectors are before the throttle plate that makes it TBI? Because there appears to be at least 10 throttle plates here. And each throttle plate leads to it's own individual runner?
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So, as long as the injectors are before the throttle plate that makes it TBI? Because there appears to be at least 10 throttle plates here. And each throttle plate leads to it's own individual runner?
Kind of, TBI is where fuel injectors are located within the throttle body, either before, or after the throttle plates, where as MFI,multi-point, each injector is at the end of an intake runner, right before intake valve, normally pointing right at the valve. Direct injection, the injector squirts straight into the combustion chamber.
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So, as long as the injectors are before the throttle plate that makes it TBI? Because there appears to be at least 10 throttle plates here. And each throttle plate leads to it's own individual runner?
Kind of, TBI is where fuel injectors are located within the throttle body, either before, or after the throttle plates, where as MFI,multi-point, each injector is at the end of an intake runner, right before intake valve, normally pointing right at the valve. Direct injection, the injector squirts straight into the combustion chamber.
This is correct.
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What would the wonky one GM put on the vortec ?
With the injectors and tubes and valves and more tubes ?
Sent from my iPhone using Tapatalk
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Whether you are referring to the 90s model Vortec small blocks or the 99-newer Vortec LS series engines, both are Multi-Port. The 90s Vortecs have the injectors at the ends of the intake runners, spraying directly into the intake runners of the cylinder heads. The LS engines are the same. It's the way that each engine was designed that makes them look different because the 90s are concealed and you can't really see the injectors but the LS engines injectors are exposed. Also the LS engines have 2 fuel rails supplying the injectors for each bank. The 90s have 2 fuel main fuel lines that go to middle of the intake and then the fuel is distributed to each injector from there.
Both are the same but setup differently.
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Maybe my definition of TBI is wrong.
For me fuel delivery electronically controlled and injected before the throttle plates equals TBI.
Regardless, the video of that 3.0L V10 Renault F1 engine spraying fuel into the Venturi's before the throttle plates at 20,000 RPM is simply awesome!