Quote:
Originally Posted by jessrayo
If you don't want to make any changes to the fuel system at all, 6 psi is going to be what you want. 6 psi on a stock engine is going to be competitive with all the other kits out there around 550 whp. When the new LT1 superchargers from Eforce, procharger, magnuson came out I was wondering why they all were only using about 6 pounds of boost. Now I know, that is about what the stock fuel system will support in this engine. The ADM LT1 car with LT4 supercharger is making more boost but he includes fuel system upgrades in the kit. When Redline did their first stage "stock engine" turbo kit they upgraded the tank pump right from the start and made a very respectable 657 whp. Just based on what the guys at Redline have done, I'm guessing there is another 100whp available in upgrading the lift pump in the fuel tank. That is a lot of additional power if you can get the corresponding air into the engine.
I assume AGP will eventually have a kit designed to run at its maximum efficiency on the stock fuel system with only 6 pounds of boost. The thing about turbochargers is the turbo is an inertia system driven by exhaust gasses and not a belt like a supercharger. That makes them more efficient in the long run but to minimize turbo lag you have to be pretty specific about the size of the turbo you install. The further a turbo gets from it's peak efficiency the more you are going to feel it in the car. My ZL1 has twin turbos that can make 900whp each. If I tried to run them at 6 pounds of boost...they would come on so hard they would hit like shot of nitrous and then the wastegate would just open up and bleed all the "extra boost" into the atmosphere. Actually my ZL1 does this now if the supercharger is not on the car but it is a 1000whp shot.
The turbos I have in my '16 SS are good for about 400-450whp each. So running the turbos at 6 psi and 550whp is still pretty far below the best efficiency of these turbos on my car. AGP is upgrading my first stage of fuel pump now.
I have not seen a lot about this on the Camaro boards but the direct injection LT motors have a 2 stage fuel pump system where the LS motors just had the one stage. Direct injection must have a lot more pressure because the injector is spraying into a combustion chamber that is in a compression stroke where the old system sprayed into the air that was either atmosphere or boost. I don't remember my exact physics but one atmosphere is generally equal to around 15 pounds of boost so 15 pounds of boost with all other variables equal is about twice the air pressure. Well, LT1 is using 11 to 1 piston compression. That is potentially 5x more pressure than you are ever going to see in a LS fuel injection system. So LT adds another mechanical pump with camshaft lobes is what I'm told. On the "at the limit" builds on the Corvette boards getting fuel is actually more of a factor than the air. For years I have been saying that airflow available from the forced induction system has always limited max power potential of these engine. It seems I may have to change my tune to the real power limitation of these DI engines is fuel delivery.
So far most of the forced induction kits are set up to give more air but it seems obvious to me at this point that some fuel system upgrades will be mandatory to tap into what these engines can really do with the air available from a supercharger or turbo.
Within the next couple of weeks we will have results for my car with a lift pump upgrade. For the guys that know me, it probably is just a matter of time before the cam pump is upgraded. Once I start to mod a car, it can be a bit of an addiction for me.
|
Thank you jessrayo for the input and information. I do have a lot to learn, obviously. For now I will keep on researching and I will wait for AGP to come out with a kit. Hopefully, they will have a kit with different "levels" of power that will include everything necessary to get it done. I am still on the fence regarding cost, simplicity, and mainly reliability when it comes to an aftermarket FI system (be it a PD, Centri, or TT system). PD SC systems seems to be the easiest setup but I am not sure about that either. This is my DD which I am looking to add an extra, nice punch to it. For no reason besides liking the number, I would love to have 600rwhp (would prefer no Meth). Not even sure if that is attainable without major changes to the car. Cannot afford a ZL1
.
so I will work with what I have but it is still a DD
Always open for input and suggestions!!
Thanks again and I can't wait to see your results!!!