TD27T how to boost more

[RB_FIEND]

hi all. iv got an old d21 terrano running a td27t, now i a top mounted an old gtst side mount intercooler i had lying around and a bleed valve in the turbo actuator line .

my problem being i cant seem to boost over 17psi and it will only creep up to that in 4th and 5th gear otherwise 15psi is the max i can get out of it.

now im no stranger to turbos in the petrol world having built quiet a few 300+kw rb's but this has me stumped iv even pulled the boost line right off the actuator in order to free boost with no success.....????

where am i going wrong and what am i missing here ??

ideally i would like to be boosting 20-25psi as iv heard that these motors are built like a brick shit house.

any info would be greatly appreciated

[sibainmud]

You won't get much over 16 psi with standard dump and exhaust. When you get up into the higher boost the turbo will die. 22psi is max with standard turbo but it won't last long at that.
Plenty of threads here on it, just search

P.S, Welcome to ORE.

Cheers,

[RB_FIEND]

thanks heaps
sweet so exhaust is whats holding me up il go to the scrappy this weekend and sus out some tube what would be a good OD pipe to use 2 1/4- 2 1/2 ??? lol iv got a couple of spare turbos siting around including a 25det one but thought it may be a little to big on the exhaust side to spool fast enough.

oh im a welder fabricator by trade with my own equipment, so fabrication wise if any one needs exhausts -intercoolers ,rust cut n welded, suspension arms modded...... ........... the list goes on let me know ... North shore based

[lincooln]

2.5" exhaust is best for the TD27, though with diesels you can't seem to go too big.