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gonna have to get my car dynoed when it comes (eventually), hopefully after some bigger injectors go in and raise the boost a tad, first i have to get it engineered and rego'd tho :P

hrmmm watch this space, twin turbo RB20 R31 has arrived today, drove it down to autosport engineering to get started on it.

The previous owner said it made around 160rwkw and the mods are as follows:

FMIC, twin turbo setup using RB26 turbos and manifolds, 3" exhaust with 3" hi flow cat, 700hp fuel pump (have to ask him what brand or dig up the receipt), heavy duty clutch (once again have to dig up the receipt or ask him), microtech LT8 ecu, twin pod filters.

I must admitt, when driving it, it did feel like it went hard, even though i wasn't pushing it too hard, but the figures he told me were, well, somewhat lower than what i'd expect with this sort of setup. ATM it's running 9psi boost and injectors are at max or very close to max duty cycle (standard RB20 injectors, had some 800cc/min ones on but the bloke said they were meant for rotors to he took em off and went back to standard as they were stuffing up or something).

Can anyone tell me if these figures look about right? I might get it re-dynoed/do another power run once it is engineered to see for myself.

anyway, would these figures be fairly typical of a setup like this? (not common, but if you go off factory turbo specs it might give you some idea/grounds for comparison)

Sum it up?

intake, decent sized turbo, efficient cooler, good dump, 3 inch minimum exhaust, injectors, fuel pump, ecu with a good tune, big hit of boost, wait untill about 4,000rpm for the turbo to wake up, HANG ON while it skates across the road = 260rwkw.

Oh, last but not least the most important mod of all, MONEY!!!!!!!

Sum it up?

intake, decent sized turbo, efficient cooler, good dump, 3 inch minimum exhaust, injectors, fuel pump, ecu with a good tune, big hit of boost, wait untill about 4,000rpm for the turbo to wake up, HANG ON while it skates across the road = 260rwkw.

Oh, last but not least the most important mod of all, MONEY!!!!!!!

i'll add,

Z32 airflow meter, unless your obviously using a MAP sensor in which case you can remove the AFM restriction :mellow:

with RB20 the best options for ecu are: remapped stock ecu or Apexi PowerFC.

my 2c.

  • 2 weeks later...
  • 2 weeks later...

Well finally drove my car today after 3 months off the road putting all the original kit on (had to do pretty much everything again as the crazy japs bodged everything). but anyway feels fast, very laggy though, as in doesnt pull boost till about 4k and full boost by nearly 5k (even with the rb24).. hopefully get it on the dyno on monday to check that everything is sweet a/f and knock-wise and i'll post up my results.

gearbox doesnt sound promising, gave it two quick squirts in 3rd to about 6k and its already sounding like the mainshaft bearing has collapsed.

update early this coming week and hopefully gearbox lasts the dyno run and i can make it into the club :blink:

dodgy phone pic:

post-1089-1134215804.jpg

Edited by kwazza11
Well finally drove my car today after 3 months off the road putting all the original kit on (had to do pretty much everything again as the crazy japs bodged everything). but anyway feels fast, very laggy though, as in doesnt pull boost till about 4k and full boost by nearly 5k (even with the rb24).. hopefully get it on the dyno on monday to check that everything is sweet a/f and knock-wise and i'll post up my results.

gearbox doesnt sound promising, gave it two quick squirts in 3rd to about 6k and its already sounding like the mainshaft bearing has collapsed.

update early this coming week and hopefully gearbox lasts the dyno run and i can make it into the club :P

dodgy phone pic:

holy fiznuck!

whats the ar on that turbo? from the pic the housing looks absolutely ginormous!

just curious but how do you know its a rb24?

also is that the gtr intake manifold mated to the rb20?

ar is unknown probably a .82, wheels are huge though, 72mm front and rear! its a kkk k27 and apart from that i've got no info on it.

bought the car in japan with the gtr crank and rods with tomei 82mm pistons already in it. havent actually pulled the sump off and measured the thing but from the feel of the motor with standard everything its definately more torquey than my last rb20.

and yea manifold is 2/3rds rb26 and 1/3 rb20. basically rb26 injector bosses welded to the plenum then that welded to the end of a rb20 manifold. not the most advanced piece of kit but should do the job now that i've ported it to get rid of the weld protrusion they left in there.. :)

post-1089-1134268990.jpg

  • 2 weeks later...

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