Boost2NA

Yeah we just did my LS-Vtec on my 99 Si. It has a fully built bottom end with a custom turbo kit. Ive been driving it around breaking it in for a little over 500 miles. I just wanted to see if v-tec would crossover (make sure we did everything right). Vtec worked like a champ. Well after driving a coulple more hours, I wanted to start throwing some low boost at it (2-3 psi). It spools up real good and wants to boost but once the boost gets past 1-2 psi the car starts spitting and sputtering. Im not sure why its doing this, not sure if its fuel prob, vacum prob or whatever. I have no clue on what it is. Note car is still being broke in, hasnt been reved over 5500-6000 and no more boost than 2-3 psi. Im running my stock B16 injectors for now. Could the extra .32 liters of displacement cause it to run that much more lean(block has been bored by goldeneagle). Fuel set up for now consists of my fmu and a holley intank fuel pump. Which is all coming off at 1000 miles when hondata ges on. Thats why im really not to worried about it but just wondering why its running the way it is cause this set up ran fine when my b16 was in there.

Boost2NA

also i forgot to mention that the ecu is throwing CEL code 23. this is for the knock sensor not being hooked up with Ls-Vtec. Can this have anything to do with it at all

SpoolinSol

Do you have the Knock Sensor plugged in? Also is it hanging, or did you ground it?

As for your other issue, do you have a Missing Link hooked up to the Map Sensor? or any type of check valves?

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