Most powerful bolt on turbo for RB25det?

[princegary]

Hi,
from what I have read, am I right in thinking that the largest bolt on turbo that fits the standard manifold is the HKS GT 2835R Pro s 0.64AR? This turbo is rated to 420ish hp but is this @ the fly? I recall being told by RSP that they can uprate the standard turbo to flow enough for 400ish....

Somebody must be using this turbo and has maxed it out surely...

Any turbo suggestions appreciated.

G.

p.s, i'm ideally looking for a turbo that will handle enough flow for 500hp (magical number)

doh ! please move to tech section

[RoboPope]

Nope incorrect, the HKS GT 3037R Pro will fit too

~420bhp or so yes at the fly, mine makes more and has positive boost at just over 1000rpm with WOT

Yes 400 or so from the stock one but thats with work not just a change to steel internals jobbie and they tend to be a bit short on volume flow too

And no the 3037 doesnt do 500 either you will need something bigger, a 3240 maybe or something similar but that will take some work

Pope

[princegary]

Thanks pope. So the oil/water lines correctly match? Do you have any dyno graphs of your setup?

I guess it would be false economy to go for something that won't make the 500mark...i'd probably just want to upgrade it further down the line. Even if i'm not using it to full potential atleast it will be available, but with the expense of more lag probably.

[Gambit]

I heard somewhere the standard exhaust manifold is too restrictive to flow 500.

Or was that just to make me spend more money lol

[Andy W]

nope

[Gambit]

Thank god for that, the hassle its been to make it fit if i said i didnt need it im sure id be shot

[Spearmint]

I've read that the standard exhaust manifold can 'just about' support 450bhp. I have 425 ath currently so work that one out!

[princegary]

right, another question....if I go top mount, will I need to relocate/remove any components? i.e, pas/aircon etc... turbos i am looking at now are TO4Z, T67, 3240, TD07s.... Anybody running any of these on the RB25det? If so, what are the spool charcteristics like. Instant response/low lag isn't really a major concern as i'd just spin the wheels anyway so rather decent boost, say .8 bar, by 3000, 1.5bar by 4500...I like the turbo boost.

looking for a new manifold now.

[RoboPope]

Well I'm changing my 2835 for a 3240 so I will let you know

Pope

[princegary]

good good. Just be quick - i'm itching to mod this car a lil bit more
Did a read up about the 3240 and it seems like a very good turbo.

[Ahapartridge]

What's your budget for the whole engine bay then Gary?

[princegary]

There isn't really a set budget - I can never keep to them. I'd say £1500 for the turbo upgrade ideally. Would be nice to get something sorted while we have such good weather. I still have 740s to put on too, and i'll leave mapping till all the parts are bolted. Oh, the AFM needs fitting too.

Won't run a ton of boost through it till atleast the headgasket is upgraded though - don't wont to chance blowing it. 500hp is my final figure on the GTS-t, then i'll probably get a GTR to play with next year.

[Ahapartridge]

So what other mods do yu have at present?

[princegary]

just the usual stg1, braided hoses, 800mm fmic, 3" exhaust system, Power FC, Blitz EBC, Apex-i power intake, walbro Fuel pump, front/rear strut braces...

740cc inj to fit, oil cooler to fit. Possibly an Aquamist system too.

I could fabricate downpipes/oilfeeds/screamer pipe myself as I have done this before, however that was before I was at my present job and had more time to fiddle about. I do own another 6 cars so keeping the skyline off the road is no problem apart from the fact that I love driving it about and i'm uncertain how long it would take me to complete the upgrade. That's kinda why I have been looking for the easy bolt on - that way it could be fitted in a day/weekend and then mapped the next or mid week.

[Andy W]

personaly, chuck that lot on with a £1500 2835 pro S get it to around 400 hubs flog it and buy the GTR your looking for......or go the whole hog with the GTS-t & end up with a monster RWD car & forget the GTR