Boost Tapering Off At High Revs, Rb20

[mattysaidso]

hey

just did a search and came up with a million topics but nothing productive.

i have a rb20 (r32) all stock with just a cat back exhaust.

making full boost which is about .7 - .8 bar. but, by redline this is down to .5 bar. how can i prevent this? without using a electronic boost controller.

can i modify where the wastegate actuator sits? or how far the rod from it moves?

new wastegate actuator spring?

other options?

thanx in advance

matty

[WazR32GTSt]

full 3" exhaust

turbotech boost controller

[CEF11E]

if you have toe stock RB20 turbo it is not able to supply enough boost pressure at high RPM so it will allways taper off. Bigger turbo FTW

[GTAAAH]

I second that, mine really died out after about 6krpm, need a new one if you wanna see power to redline. I'd go exhaust first though if you haven't already, you'll need a decent 3" system with this turbo or your new one to help out with keeping up the boost

[_8OO5TED_]

an electronic boost controller hold boost much better also.

[mattysaidso]

thanx for the promp replies.

yeah it only has a cat back as current. full exhauast and rb25 turbo are next on my list.

are there any other options before those mods?

[GTAAAH]

You mentioned you didn't want a full electronic boost controller, but try a mechanical one. Search for that $22 boost controller thread, i got one of these and it helped reduce lag and held boost later into the rev range. Other than that a remap will help but i wouldnt do that until you had the new turbo installed (as it'll need redoing)

[Cubes]

Definitely a good full exhaust and most importantly a 'good' dump pipe. I bought a $1660 exhaust system and found the dump pipe to be complete crap. The 3" pipe didn't stretch over the flange correctly causing a v rise about 15mm smack in front of the turbine wheel. Bodgy bastards.

EBC's do work. BUT a free mod is to modify the actuator. I enlongated the 2 mount holes so that I could adjust it. Worked so well I sold my EBC.

[mattysaidso]

pm sent cubes