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Hi folks :) First off sorry for what is likely to be a pretty wordy thread, but i figure i'm best just throwing down everything in one go and sort whats left over when the time comes.

Ok i've decided over the course of the last few weeks what i want to do with the car. I've only had it for around 5 or 6 months, and the plan was originally to keep it for a year then promotion permitting jump over to an R34.
Trouble is, i've got the promotion but i've grown to like it too much so i'm keeping her for a while and investing in some more shove and get a 4x4 for the longer more boring daily drive stuff and lugging bikes and snowboards around.
I've thought about a few options, including going down the RB30 route, but i figure i've got a good low milage engine in there already, so i might as well work with that for now.

I'm looking for the world on a stick really, around 600 -650bhp at the wheels, but i'm aiming to keep a fast spooling low lag setup that is still perfectly useable on the road, and above all, reliable, whilst being responsive and powerful enough to show up some more precious metal should it see a track.

So over the course of the next few months i'm gathering bits for a build.
Any help with potential specs would be appreciated.

To start with i'm getting a twin plate OSG clutch, as mine doesn't have much life left in, and is barely up to the job of 450bhp. The gearbox is a concern but i'll ask about that once i've got the engine side of things decided upon.

Engine wise i was just planning on going down the 1mm oversized forged pistons and rods, and metal headgasket route originally to keep things safe, but i've been toying with the idea of a stroker kit and have begun to wonder if it's worth stroking the engine when going for 600bhp. I'd like as much torque as possible, and to my mind stroking the engine would help, but do the likes of the 2.7 and 2.8 kits have any detrimental effects on everyday useability of the car? particularly when driving around town etc , and is it worth bothering with for the level of tune i'm looking at?
Also curious as to how the stroker kit equipped engines turbos spool compared to non stroked. any thoughts?

The turbo kit is what i've struggled to decide with, but i'm fairly keen on the idea of the HKS GT RS' kit, retaining the two turbos. I know there's arguements for and against going single turbo, but for now i think i'm best off sticking with 2. What power is the RS kit good for? i've read mixed reviews of them on here, on skylinesdownunder and skylinesaustraila etc all with different opinions of what power is achievable,
The turbo's they seem to be compared with the most is the Garrett GT25/40's, but i'm not sure they're up to the job of my power requirements.
Is there anything out there that i might have overlooked turbo wise that should be considered for my power aims? i'm not tuning just for the sake of reaching a set target power wise, 600atw is purely a ballpark figure give or take, But i am pretty sure i'd like to retain the twin turbos if it's feasibly possible. If this is a stupid idea please feel free to tell me and justify why :D

I'll be sticking a set of fairly mild cams in there to help the spool and power delivery without shifting the power up to the top of the rev range too much, probably a set of Tomei 260's, and a set of uprated springs. haven't really looked into everything with that respect yet but i'll be discussing it with my tuner soon, any thought or recommendations there appreciated :)

Managment wise i've got a powerFC ready to install, but i may well go for a motec setup later, anyone used these on the GTR's and if so any comments ?
Safety wise i'll be going for a larger and baffled sump and probably an accusump, with a relocated oil filter kit and a good sized oil cooler as i've noticed oil temps are pretty easy to send to a higher level than i'd like them to be at with 450bhp.

Fuelling i haven't really looked at so any advice there is appreciated. I was thinking 720 injectors should be up to the job coupled with a rise in fuel pressure and an aftermarket fuel rail. Pump wise i've got a walbro in there at the minute which i'm hoping will be upto the job but if not i'll incorperate a booster pump setup.

The drivetrain i've got to have a look around, i'm pretty sure it'll lunch the box that's in there in a whim with that power, but i'm not looking for dog boxes or sequential if i can avoid it. I'm interested in tinkering with the gearing and final drive of the car but i've not looked into that in any real depth just yet, but i'll be uprating the diffs for sure, just not sure what with yet :)

So, if you've read through this far thanks, any thoughts as to what i'm looking at doing? Tuning skylines is pretty new to me, but coming from a background of other nissans it doesn't appear to be too different :) but if i've overlooked something critical or the setup i'm thinking of sounds crap let me know what you think and why :)

Thanks for reading,
Stu :squintdan
 

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GT-RSs might just give you 650 the power you want, but you need to rethink your fueling idea if you really want 600-650awhp; 720s wont be enough.
Also, if you go GTRS, you should definitely consider the HKS 2.8 as they are matched by HKS by design.
Why would you think there is anything detrimental about having a stroker kit for everyday driving - it improves the low down response and the turbo spoolup will be quicker.
 

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As Bean has said the GT-RS's are designed to work well with the HKS 2.8 engine so will feel laggy on a 2.6 and will have shuffle aswell..........2540's also work better on 2.7/2.8 as they tend to be a tad laggy.......need the extra cc's to get the benefits out of these turbos.

Get a rebuild done 1mm over sized pistons and some rods, HKS 2530 turbos, tomei 260 cams, 720 injectors and then the usual bits to go with it, fuel pump, ecu, afm's etc.....

Will be good for 600 relable horses and maybe a bit more and a very driveable car!

Harry
 

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You say you have a good low mileage motor and want to stick with that and then you talk about stroker kits and a boring the block etc, if your prepared to do that why not go the RB30? you want drivabilty, torque and good power, you get them all with a 30.
 

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I never understood the 'turboshuffle/synchronizing' problems occuring when using HKS GT-RS turbo's and 2.6Liter. Compared to a 2.8L displacement it's a difference of 7.8% So you need to driving the RB26 7.8% higher in revs compared to a RB28 (for example: 2.8L/2,500rpm <=> 2.6L/2500rpm x 107.8%= 2,695rpm).

I can't believe HKS made the GT-RS kit for RB28 engines only. The fact that they published GT-RS powergraphs based on the RB28 doesn't mean the turbo's are only meant for that setup.

Wouldn't it be possible then to smooth out the shuffle using precise mapping techniques? Use MAP sensoring instead of MAFs?

Henk
 

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Lamb's recipe looks pretty good value for money.

Everyone seems obsessed with stroker kits on the forum.
I would rather leave it 2.6 and spend the money on the chassis or the mortgage.
 

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skyrocker said:
I can't believe HKS made the GT-RS kit for RB28 engines only. The fact that they published GT-RS powergraphs based on the RB28 doesn't mean the turbo's are only meant for that setup.

Henk
No-one said that the GT-RSs can't be put on a RB26, however, I know from speaking to the HKS engineers at the AutoSalon when the GTRS was launched that the GTRS is designed to be a better match with their 2.8 litre kit.
(Of course - it could be said that all turbos work better with more displacement anyway)
 

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skyrocker said:
I can't believe HKS made the GT-RS kit for RB28 engines only.
Henk, no one has suggested this mate..........just a simple case of they are designed to work more efficiently on the 2.8 for best results......hence why all HKS's test results for this turbo has been on a 2.8!

There are people on this forum running GTRS's on a standard engine.

lightspeed said:
Lamb's recipe looks pretty good value for money.

Everyone seems obsessed with stroker kits on the forum.
I would rather leave it 2.6 and spend the money on the chassis or the mortgage.
Totally agree....but hey.....each to there own!

Harry
 

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Lamb said:
Henk, no one has suggested this mate..........just a simple case of they are designed to work more efficiently on the 2.8 for best results......hence why all HKS's test results for this turbo has been on a 2.8!

There are people on this forum running GTRS's on a standard engine.

Harry

Bean said:
No-one said that the GT-RSs can't be put on a RB26, however, I know from speaking to the HKS engineers at the AutoSalon when the GTRS was launched that the GTRS is designed to be a better match with their 2.8 litre kit.
(Of course - it could be said that all turbos work better with more displacement anyway)
Well not in this thread nobody has suggested this; you and Bean are correct :)
I am addressing the so-called 'turboshuffle problem' tho when using the GT-RSs on stock engine. Just to be informative to those using this setup (RB26, GT-RSs): HKS mapped their engine with the use of the FCON V-Pro MAP sensoring, which is more accurate compared to MAF sensoring. Just my 0,02c correct me if I am wrong. This could be the solution.

Henk
 
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