ok i got a b18c1 in my hatch.its got a built bottom end pistons rods etc.running t4 turbo 2.5 downpipe exhaust and ic piping.everything was fine till i installed a bigger intake manifold port matched to the new throttle body at 68mm o and i did cam gears.the problem is now what i believe to be a turbo lag.the boost is kicking in way later like at 4 or 5 rpm.can anyone help me figure out how to solve this problem?im running 13psi do i need more?bigger turbo?help please

 

I'm assuming you have checked for leaks already... Check silicone clamp areas and also bolts on the intake manifold where you touched or removed.

 

Bigger IM = More space to fill

More space + same turbo pushing the same amount of air = More time to generate the same PSI


This is assuming there are no leaks

 

ive checked the ic piping and some other places. ill double check but if its not that then what do i do

 

so should i push more psi?

 

Question answered dude, lol.

 

You have a T4 turbo and boost comes on at 4-5krpm, whats the farking problem?

 

Oh and I didn't look closely enough, you really should be running a 3" downpipe... 10PSi+ is 3"+. Might help some. And what fuel management system are you using? What tuning? All these facts play in this equation.