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Rb27/ Rb28 Vs Staying Rb26


ibrox90
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So,

I've been looking at a possible engine rebuild not because I need to, mainly out of sport. So I'm in no real rush. Although new turbos are coming soon and I'd need to choose between HKS GT-RS and GT-SS.

I've been looking at a lot of forged kits as well as individual component prices and the like.

Now of course when you talk about rebuilding a 26 a lot of stroker suggestions come up in the community of car nuts and for a long time that's what I wanted to do. And it should come up strokers are nucking futs.

However,

all I can gather that stroker gets me is more torque and a lot more down low. (Which Is what I would like.) and more POWAAAAA!! ( providing its the right turbine(s))

BUT.

No one ever talks about staying 26.

I'm wondering if there's anyone out there who's ran both and could provide feedback. Or someone who went from a worked 26 and then changed the crank.

or better yet someone who's gone from a 28 and then back into a 26.

I feel like I should say that I'm not huge on chasing power numbers. For me its about response first . I want 1000-9000+ rpm to happen asap.

I searched ( everyone always fires that out) and its not what I'm after. Nor am I after some dyno sheet print out. ( dyno sheet to support someones opinion is great)

I'm really after opinions on the "feel" of the car and differences noticed. I understand that this is a hard question because obviously if you go from a stock 26 to a worked and tuned forged 28 running more boost its going to feel like an animal.

Finally, and I mean this in the nicest possible way and do not intend to upset anyone. But if you drive your mums r31 and "read about a 28 in performance imports once" or "read a bit on forums" probably don't comment, because I doubt you'll be able to answer my follow up questions.....sorry I know it sounds douchey.....but it shits me to tears.

Cheers


Edited by ibrox90
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First of all no goes for 2.8 to 2.6

Second of all there is a massive difference between GTR's and GTSS.

Third of all, if your running your engine to 9000+ rpm your running the wrong turbo and cam timing.

If you want to have a look at a good 2.6 result google "83/75 GTR Joey" not much will beat that In terms of 2.6

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As far as im aware GT-RS are better matched to the 2.8 and the SS to the 2.6.

....hks GT-RS vs HKS GT-SS ???? I assume you meant Skyline GTR vs GTS-S.... . I'm fully aware of the difference...

Changed original to avoid confusion.

Not disagreeing. With the rev limit comment. But the most animal GTR I've been in reved to 11,000 rpm very very quickly and its something I enjoyed.

Edited by ibrox90
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Would be better going for a set of GTX2867's in -5 housings*, if you want the sort of power GTRS's make.

End of the day it depends what you're going for power wise, there's a huge gulf between GTRS's and GTSS's as said above

*i believe this is possible, check with your local turbo vendor

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If money is no issue, which it shouldn't be if you are working with a GTR, then the 2.8L and a single turbo would be the best path in my opinion.

Unless you fancy twin turbos you can pull more response and power from a modern single than those HKS turbos that are fairly old technology now. Personally wouldn't put either of those turbos on a 2.8L and there is a big difference between the two as stated.

If you can provide more information about your intentions you might get some more help because you seem to already know the answer to your question.

Personally I wouldn't pull rebuild or strip down my GTR just to put a 26 back in it. The people who have put in the 2.8L or larger never look back and its for a good reason.

I'd reconsider turbo choices also unless you have your mind set on those particular turbos. In the end it all comes down to preference really.

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Have you considered a RB30 bottom end?

GT-RS would be OK with the 3.0, better again with a single.

I wouldn't consider a 2.8 over a forged 3.0......but hey that's just me.

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I'm of the opinion that building a 2.6L or 2.7L would be a waste of time.

(Sure a 2.6L if the budget is tight & want the "safety" of stronger internals)

But buying a kit for 100cc seems ridiculous!

If you are gunna build, build as big as possible if you want the down low torque and response.

Seems you are limiting yourself turbo wise with the above mentioned turbos?

Whats your power goal and what fuel do you plan on burning?

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I've had stock RB26, 700kw? 10 000rpm RB26, and now RB30 with 5-600kw and it is by far the quickest and most ridiculous and I can't find the need to rev it above 6k very often on the road.
I don't think I'd ever go 2.6 again, Unless it was because I just wanted a budget build between 3-400kw. Which is all that is required with GT-SS turbos.
As mentioned many times over, GT-RS turbo's aren't worth using.

Buy the most capacity you can afford to suit you goals.
Firstly decide what they are, because the two suggestions you chose are chalk and cheese

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just to throw it in single while i want to I cant due to the legality and the cars is regularly inspected in various states. Due to moving interstate alot.

It seems that we are some what hung up on the turbos. Obviously I mentioned them earlier simply in passing.

This is not a turbo choice thread ........yet.

Interesting to see how one line gets picked out.

Is there any argument for keeping the displacement at standard.

As I said before I'm not particularly interested in chasing numbers. If I was I would still have the V8. However realistically it'll probably end up around the 400 kw mark or just shy of.....that said I dont want a lag monster.

as for fuel at this stage for at least the next few years I will be using BP 98. E85 is on the cards ... but much further down the track. Due to living arrangements and constantly moving house e85 is just to hard to source.

Edited by ibrox90
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The only argument for stock displacement is cost or if you have to adhere to guidelines.

The reason turbo's have been mentioned by everyone is because no one wants to see you make the mistake of buying the GTRS sized turbos and the fact you said they are better matched on a 2.8. Which may be the case, but they are still not the best choice for the power and response, or lack there of.
The next size down HKS2530 or Garrett 2860-5 will be a far better choice.

If you're not chasing numbers, leave it stock and put 2860-7's on.

Can't out stroke a poor setup.

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What jangles said about cost or guidelines for remaining 2.6L would be my vote, otherwise most go 2.8L or RB30 bottom end conversion.

If your current motor is healthy you could do some modifications to it and get between 300-400kw on 98 with the right set of turbos and keep it responsive. But you lose reliability and run a higher risk of the motor giving in at some stage depending on many conditions, the tune being a big one.

If you go with the 2.8L or RB30 you give yourself that extra low down torque as an advantage, on top of having a fresh engine.

In the end, your power figure can definitely be achieved on stock displacement and with the right setup would be a great car to drive and plenty of power for the street.

Reliability and properly tuned car would be the best solution, regardless of displacement size as your power goal can be achieved from stock displacement as mentioned and it will not be considered a lag monster.

rb28 or rb30 would be my recommendation. Understanding what you want from the build/car as an end goal helps with these decisions also as they can be quite difficult and costly to get wrong.

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What jangles said about cost or guidelines for remaining 2.6L would be my vote, otherwise most go 2.8L or RB30 bottom end conversion.

If your current motor is healthy you could do some modifications to it and get between 300-400kw on 98 with the right set of turbos and keep it responsive. But you lose reliability and run a higher risk of the motor giving in at some stage depending on many conditions, the tune being a big one.

If you go with the 2.8L or RB30 you give yourself that extra low down torque as an advantage, on top of having a fresh engine.

In the end, your power figure can definitely be achieved on stock displacement and with the right setup would be a great car to drive and plenty of power for the street.

Reliability and properly tuned car would be the best solution, regardless of displacement size as your power goal can be achieved from stock displacement as mentioned and it will not be considered a lag monster.

rb28 or rb30 would be my recommendation. Understanding what you want from the build/car as an end goal helps with these decisions also as they can be quite difficult and costly to get wrong.

Ultimately thats the big ask. As previously said having owned a big KW car before its not something i aspire to for me free flowing revs are important. I really dont want to get stuck into a power goal as i feel that its some what superfluous.

I hadnt really considered an RB30 at all and really id like to stay away from that.

In terms of my absolutes .... NEEDS to be the same block

Needs to look stock

the latter means that there's bolt on limitations too. So while X power figure can be done with bolt ons... some bolts on are out of the question... hard piping etc etc.

As for what I want from the car.

I've had a big kw Ford and it was rather highly strung and very close to the ragged edge in terms of driveline safety because at the time I wanted a dyno monster nothing else... essentially i didnt care if my torque band was in the last 1000 rpm... as long as it made 500kw.

NOW i want a car i can thrash and have zero worries ( and thats always relayed to my tuner) which is why a gearbox rebuild is also important to me .

this thread was merely a gauge. Alot of rebuilds dont go stroked even though it seems like such a massive gain . Ive seen so many in the 2.8 corner and very little representation from the 26 corner.

as for jangles comment. This is why i want engine choice done first. Id hate to rebuild and find that turbo size is holding it back. Id much rather go fo X turbo and have a lag monster or have the turbos not working to full capacity for a year before rebuild , than rebuild and find that the turbos just arent up to the job

Edited by ibrox90
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Ultimately thats the big ask. As previously said having owned a big KW car before its not something i aspire to for me free flowing revs are important. I really dont want to get stuck into a power goal as i feel that its some what superfluous.

I hadnt really considered an RB30 at all and really id like to stay away from that.

In terms of my absolutes .... NEEDS to be the same block

Needs to look stock

the latter means that there's bolt on limitations too. So while X power figure can be done with bolt ons... some bolts on are out of the question... hard piping etc etc.

As for what I want from the car.

I've had a big kw Ford and it was rather highly strung and very close to the ragged edge in terms of driveline safety because at the time I wanted a dyno monster nothing else... essentially i didnt care if my torque band was in the last 1000 rpm... as long as it made 500kw.

NOW i want a car i can thrash and have zero worries ( and thats always relayed to my tuner) which is why a gearbox rebuild is also important to me .

this thread was merely a gauge. Alot of rebuilds dont go stroked even though it seems like such a massive gain . Ive seen so many in the 2.8 corner and very little representation from the 26 corner.

as for jangles comment. This is why i want engine choice done first. Id hate to rebuild and find that turbo size is holding it back. Id much rather go fo X turbo and have a lag monster or have the turbos not working to full capacity for a year before rebuild , than rebuild and find that the turbos just arent up to the job

The bottom end really isn't going to influence a great deal, with the TT options, on 98, if you're only wanting to retain the rb26 block, assuming you aren't considering spacer plate engines.

I feel that GT-SS twins and upwards in size aren't ever going to hold you back from the power goals you aren't worried about.

Quite the contrary, You won't be able to get the most out of the turbos without a substantial build and head work.

You will find GT-RS aren't going to be an efficient choice, ever.

2.9, GT-SS/2860-9 or -5 on 98, enjoy.

p.s. my rb26 was as free revving as it gets, even had a 4500rpm power band....but the 5500rpm that had nothing made it useful for one thing only.

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I don't know why you say no -one talks about keeping the 2.6L capacity - if you go to the top of this section there is the RB26 turbo upgrade thread with 25 pages of people who have done just that.

If you want a responsive stock looking 400kw have you considered an R35 GTR?

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people stay 2.6 for 2 reasons, they are tight asses and don't want to spend an extra $1000 on a rebuild (which means they should never have bought a Gtr in the first place) or they don't realize how much difference the extra 200cc makes to the way the car drives and don't think it's worth the extra $1000

But from having driven a stroker, the difference is night and day and it's worth every cent

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I don't know why you say no -one talks about keeping the 2.6L capacity - if you go to the top of this section there is the RB26 turbo upgrade thread with 25 pages of people who have done just that.

If you want a responsive stock looking 400kw have you considered an R35 GTR?

Yes briefly however ever i dont think it would look good sitting between my ferrari 458 and the veyron.........................

...................

You mean the tubro upgrade page.... that ive already said this isnt about..... or .......

Edited by ibrox90
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people stay 2.6 for 2 reasons, they are tight asses and don't want to spend an extra $1000 on a rebuild (which means they should never have bought a Gtr in the first place) or they don't realize how much difference the extra 200cc makes to the way the car drives and don't think it's worth the extra $1000

But from having driven a stroker, the difference is night and day and it's worth every cent

As long the turbos aren't GT-RS. Just ask Paul aka Piggaz.

I'd just plonk -9s on standard motor and enjoy for what it is, spend $ on suspension.

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As long the turbos aren't GT-RS. Just ask Paul aka Piggaz.

I'd just plonk -9s on standard motor and enjoy for what it is, spend $ on suspension.

Not a horrendous idea . But a rebuild is happening thats why its a question

This is exactly what i was thinking in terms of rebuild cost. Its just a smidgebof extra $$$ for a huge win .

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