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new to this so bare with me.

Just fitted a hiflowed rb25 turbo on my near stock rb20det on my r32 yesterday with minor mods fmic bov pod 3inc, and thought it would be a good upgrade considering there seem to be rather popular but im not seeing full boost till about 4800 5000 rpm is that normal? im getting a new ecu/nistune and walbro pump fitted next week. car has no low end power just dies in the ass if i drop the revs to anything out of boost.

would like to know what you guys out there with hiflowed rb25 turbos are seeing full boost at? any comments or advice tips tricks would be most appreciated cheers.

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I dont have the specs on me but I Had my 33 turbo hi flowed a few years ago for my 32 and wasn't that much different then my new current td06 setup,all round- boost vs hp vs rpm range etc isn't worth it but seen as you have it already I'd try some cam gears as It picked up around 5-600rpm earlier with em..

i run a td05 and i get boost from 3000-4000 @ 1 bar

a 32 highflow comming on that late sounds odd. have you hade it tunes at all sice the new snail?

did u actually read his post at all?

#1 its a 33 hi flow

#2 his still running a stock computer - getting a nisstune soon

and yer mate from what ive read hi flow 33 turbos are pretty average on rb25's let alone an rb20... keeping in mind that 1 hiflowed 33 turbo may not be the same as the next

Just fitted a hiflowed rb25 turbo on my near stock rb20det

Have to remember an RB25 has +500cc of displacement, as well as VCT. Cam gears are a cheap mod and adjusted right can help increase response and bring that turbo on sooner without losing power

Imo, keep the 33 hiflow for the moment and as Fornoyd20 said, get cam gears and a tune - then decide. There's the potential for a gain of 5-700rpm lower boost through cam phasing and ignition timing alone. If you can get it to 'come on' around 4000rpm, that's about the point most turbo's will be doing so on an rb20.

A mate used to run a high flowed 25 turbs on his 20 and was seeing full boost way before that. Off boost driving was pretty poor but barable. A tune would help but as said it depends who high flowed it and what bearings are used, size of wheels etc etc. Tune better fuel pump and bigger injectors and decent boost control will see gains everywhere and you will be happy. The tuner will probably play with the timing anyway.

i used to run a highflow on my rb25 ( 2871, 56trim in stock housings ) , would pull hard at 2500rpm with a bar in at 3000rpm

my avcr does a brilliant job of bring on the boost, get a good boost controller and pile on some duty early in the revs.

Edited by SliverS2

What td05 is this ? 18g 16g maybe ? Just keen to know I'm thinking of putting one on my 20 And how much power is it making ?

i run a td05 and i get boost from 3000-4000 @ 1 bar

a 32 highflow comming on that late sounds odd. have you hade it tunes at all sice the new snail?

Get a good R32 Highflow, mine is on full boost a bit after 4000rpm I think and pulls hard to the redline, right before the E85 tune was making 216rwkw with as good a response as you'll probably hope for on an RB20, drives nice off boost, remember a good tune makes all the difference.

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