I am building a turbo b18b with a greddy 18g turbo, and it is my first turbo build. I really want feed back from people who understand the 18g turbo because it is different than your normal turbo. Its max 10 psi is because of the internal waste gate, and from turbo charts I've seen on this turbo, it slowly starts to lose efficiency after about 5000rpm but not drastically. So based on this idea, building the head to rev higher would not be the smartest way to go. but I am only assuming. I want some ideas to extract the most hp out of my engine using this turbo.

List of parts already:

Greddy 18g turbo kit
3" exhaust all around
Eagle rods
Stock head
Stock Intake Manifold
Lightened flywheel
Type R tranny LSD
Clutch Kit to meet torque
Arp head studs
Better fuel pump
450cc or 460cc DSM injectors
Innovative mounts
Greddy boost controller
Dyno tune on Hondata S300

other minor things that are needed to finish the build but you get the idea.

 

boost controller + intake manifold.

 

Boost controller will only allow for about 12-14psi, and even then that is a Spike in boost, because the actuator is so low powered. The OP needs a few things from ATP.

1)ATP GT28R turbine flange - so that a better downpipe can be made
2) ATP 14psi internal gate actuator - this will be a direct replacement for the Greddy one so that you can get full potential out of the turbocharger itself.

The turbo doesn't fall off at 5000rpms, the torque is stabilized at that point. The limit to the amount of boost you can run is from your engine and map sensor when you upgrade the components that I stated above.

 

Awesome I'll probably do both of those. I knew I could get a higher psi actuator, but I didn't think it would work because of the flapper door. I thought I would have to do both. (Upgrade the actuator and change the flapper door) but even if I can get a little bit more from the actuator then its worth it.

 

Just to make sure, the ATP 14psi internal gate actuator is this one correct? http://www.atpturbo.com/mm5/merchant...egory_Code=WGT

 

Yes, though I didn't go through the site. I called in.

 

couldnt you just weld the wastegate flap shut?

 

That would actually cause him to OVERBOOST because he has no way to bleed the excess boost pressure. The wastegate would be useless, unless he were to create an elbow for an external wastegate. To weld the door shut and Have NO way to release pressure causes engine to go BOOM..