A Little Bemused About Where To Go From Here...

[Marco-R34GTT]

G'day all..

Just for a quick run down I drive a 1998 R34 GT-T.. Now recently I've had some work done to my car, I've finally upgraded my clutch (Heavy single Xtreme) and I've now got an ECU (ViPEC).. However, when I had this work done it was discovered that I had a far bit of lateral movement in my crank, about 5mm of north-south movement, the case was that the thustbearings were shot and I ended up having to get a replacement RB25 crank (Polished and machined, was only about $200). I also had some cams installed, but due to some god almighty collection of @rse-ups.. I ended up having to replace 2/3 valves, all my springs and some cleaning up had to be done... So I bit the bullet and I've gone for performance springs and 260/260 9.15mm Tomei Poncams (Type B). Basically my head is now in fine condition for what future plans I have..

Now, the issue..

I've always been in favour of displacement increase in the RB engines.. Yes stock capacity is fine and YES the tomei 2.8 kit is rather exy, however, to achieve my dream built I'm quite happy to part with the money. So, what follows? I've been thinking turbos to match such a set-up.. My primary concern is that I want my car to be driveable, responsive and to have easy/useable power through most the rev range, as I consider peak/top end power, to be very much a secondary concern. I'm in favour of something low mount, I just like the idea of not being outrageous and I really want to keep the car as inconspicuous as possible. I was thinking a 3037 low mount and if nessicary, I'd have it externally gated in order to handle the extra boot from the 2.8 litre capacity. I've been told that this turbo will not suffice and that it will basically be a bottleneck in my system (In which case, a HKS 3040 would be better, or even a T04), would this actually be the case? Is a low-mount configuration totally out of the question with a 2.8 setup??? If I was so keen to stay low-mount, could I possibly take a note from TWOOGLE and go for twin GTRS's, or is that total overkill, with a combined boost/power output of potentially 800PS???

Was also considering going for aftermarket intake and exhaust manifolds, on the exhaust side, either HKS or 6 boost, depending on availability (in which case, I'd probably need a HKS dump for the new turbo/s). Would probably go for a GReddy intake manifold, it has been done on an RB25 and it does wonders for cleaning up the engine bay and removing a plethora of annoying and performance reducing piping... Between doing BOTH in the intake and exhaust, I'm again hoping to achieve a responsive turbo/engine setup, as I've heard that BOTH of these upgrades can recoup as much as 200/300/400RPM of boost response apiece, which is exactly what I want..

Also I would have to address the fueling obviously, aftermarket rail and 600cc (or 750cc injectors?) would go in, I've already got a NISMO fuel pump... Is there anything else I'd need to seriously consider?? I'd be more than happy to even have the engine held back until I could afford gearbox/drivetrain upgrades.. I've been told that the stock stuff will take 450BHP, again, is this in fact true?? Basically, I'm not concerned about how MUCH power I make, but HOW my car makes the power... Which is why, I'm a huge fan of the 2.8 kit, with billet crank. Would be nice to have it going to 8k RPM!

Oh, and yes, I've got aftermarket coilovers and rear traction bars and camber arms.. I will be looking for either R34 GTR brakes of Brembo F50's as the dollar keeps imporving against the yen. But yes, I've address handling, if anything, just braking to go, and again yes, I run on good rubber. Toyo's.

Pleas please please, any informed/well thought out information, input, opinions are very welcome.. I'm just looking out for ideas and notes from people that have 'been there and done that'. I'm not the full bottle on this but I've read tonnes of stuff both on SAU and from import mags, please don't be condecending, but if your views differ from my vision, please, I want to hear it, but back it up with facts/examples/logic. As I, and many others, come on here to learn about our cars, and I'm still keen to learn, especially with such plans on the horizon..

Thanks very much. Let's hear it!

Ta.

Mark.

Edited August 21, 2009 by Marco-R34GTT

[SexycanI]

are you going to get what you wrote published? a whole life story

[bubba]

All I'm going to say is.. why didn't you 30 it while you had the bottom end apart?

Anything happens to my Neo bottom end and it's getting the 30 treatment!!

P.S. 3L > 2.8L

[Marco-R34GTT]

It was a tale of one thing after another... If anything I wanted to go to RB26 crank, rods and forged pistons... But yeah, didn't happen..

@sexy.

Just making it easier for people to give advice, I've got a clear sense of direction but not sure how to get there. :-)

[bubba]

You want more displacement but dismiss the 30 out of hand? but would have gone for an extra 100cc's? pfft.

[Marco-R34GTT]

Not dismissing the 30 option at all bubs.. Just that I was under the impression that the 30 bottom end would require a fair bit of work.. Plus the Tomei kit is billet, but all options are open dude!

Soz if I sounded out of order, or dismissive or something... :-)

[GTS-t VSPEC]

Mark, Speaking from experience, anything more than 400rwhp in a RWD car is overkill, yes it's fun, but impossible to get grip. I've spent more money than any sane person would and personally I'd go for a smaller responsive turbo, peak power isn't everything, response and driveability are more important.

[Marco-R34GTT]

Mark, Speaking from experience, anything more than 400rwhp in a RWD car is overkill, yes it's fun, but impossible to get grip. I've spent more money than any sane person would and personally I'd go for a smaller responsive turbo, peak power isn't everything, response and driveability are more important.

That is exactly my goal... But with discplacement increase, be it 28 or 30 or whatever.. What would be the BEST turbo to match with the increased displacement in order to attain said goals? That is what I'm most confused about.

[stormtrooper]

If you wanted a more broad and progressive turbo setup definitely go for a twin setup as you can spread the torque a bit better. GTRS's are good for this. A 30 bottom end is almost bullet proof as it is, I remember a VL with the stock 30 bottom end and a 25 head few years ago over east was running about 600hp unopened bottom end but worked top end and a dirty big turbo on it, they are tough as nuts. You're 25 bottom end would be fine for a 400hp goal though so I wouldn't worry too much about it. (unless you actually want more power AND for it to be bloody reliable).

I'm running just shy of 400awhp on my GTR mate and even I can't use all the power, the midrange is bloody awesome though, and that's where it's mostly needed anyways (as I tend to want to power out of sweeping bends all the time heh.) Only thing i want is a respray coz of the prick who keyed me

Edited August 21, 2009 by stormtrooper

[bubba]

Well considering they would have had the engine out to pull the crank out..

RB30 bottom end - $100ish

New rings + rehone - $few hundred

Crank grinding - $100ish

Balancing - $few hundred?

New bearings (mains & bigends) - $160ish

Tap tensioner location

Modify power steering bracket

Bolt head/manifolds/ancillaries on

Put back in car

That's a basic 30 build and would handle 400rwhp easy with a sensible rev limit. If you had a bit of extra coin then a crank collar a better oil pump would be on the cards.

Even cheaper if you find a good condition running 30 to start with.

Basically, if you ever have to rebuild, then the cost of going a 30 is negligible.

Edited August 21, 2009 by bubba

[stormtrooper]

If only it were the bottom ends people usually blew up

But yeah, 400 easily on a 30.

[bubba]

Engine rebuilds usually stem from something in the bottom end failing.. pistons, bearings, rods (rare in lopo applications).

[stormtrooper]

Ah, I was referring to 30 bottom ends failing. Don't usually hear too many of em doing so easily.

[bubba]

I love my 30

I miss it so bad.. been like 3 months since I last drove it

[GTS-t VSPEC]

I love my 30

I miss it so bad.. been like 3 months since I last drove it

That's the problem, rebuilding an engine is never quick, be nice to have a running car and build up a spare engine instead

[stormtrooper]

Like a mate of mine. Owns a GTI-R pulsar with a spare motor sitting on an engine hoist in his garage, he cbf working on it anymore so when he'd finished paying it all off etc, he bought a 310rwkw S15..... damn. Think we'd all love to have something else sitting around just in case. As for me, it's the wifes Echo ... lolz.

[Marco-R34GTT]

Cheers for the input lads!

Still, not too sure which way to go in terms of turbos.. What are you running bubba?? Single? Twins? That is really the major factor, what to bolt up to a 15/18 or 15/30 setup...

[Ehgriez]

Id consider the Plazmaman plenum over the Greddy, simply as I like the design better and theres less copys floating about that you might get stung with. That and it's an australian company.

I'd say a 30 would be alot cheaper (depending on how you build it ) than the Tomei 2.8 kit if you were heading down that path?

Thats really all I have on the topic, other than maybe running a surge tank as well for the fueling system?

[R32 Driver]

The dirty30 would be a very good choice.

properly balanced and an aftermarket balancer ross/ati they will rev to 8k

be considerably cheaper then a stroker kit too

Go with a big single to save alot on buying 2x the turbos,manifolds,etc

Have a read through Cubes thread. He has a low mount rb25/30 making 400hp? on stock manifolds (i think)

however engineering a rb30 and licensing it these days might be more of an issue over a rb25 with a 2.8 stroker

[N I B]

I'm waiting for Spool to release their 3.4 cranks for RB30s, RB34= More of a good thing and still much cheaper than Jap 2.8s.

Strong early power makes for a much nicer and faster drive.