-7/9s Or -5s Garretts

[Johnny]

well im lined up for a tune next friday with my 5s so ill post what it makes ill only be using stock afm tho for now....

Great man, cant wait for that; hopefully you can post an on-street impression for us? i know that fullbosst is around 4500-5000rpm but does it start pulling earlier, that familiar turbo torque at low revs

best of luck!!!

[R31Nismoid]

Ash, the point is the tuners over here are not willing to run the turbos on the limits of their capabilities and risk blowing shit up!

Hence why I said 300 to 330 RWKW from GTSS's is pushing too much and asking for trouble, thus I would go the -5's if I wanted 300 plus RWKW.

At the end of the day, what you are saying is stupid and akin to me saying, yes my RB26 can rev to 10,000 rpm, but for how long!

If the tune is good, your still running within the limits of the turbo and intake temps are still acceptable...

There is no risk. The sooner you drop the work risk and adopt the word OK - the better for everyone in this thread.

Scenario - the best workshops on the eastern shores can tune, setup and not have any problems with the cars that are doing drag, circuit, various rallys...

All of the cars doing the various things are reliable as it gets, why? Because its still within the limits. (there is a recurring theme here)

If you're gullible enough to believe what people tell you… that’s fine. I'm not.

The information posted, the actual technical data, clearly shows you that its within the limits and that you are wrong…

As long as a part is not pushed over the limit then, there is no feasible justification to question reliability.

Only when you are over the limits should this come up.

So to use your own, rather poor, example. Its nothing like spinning a motor to 10,000rpm. Why?

Because thats OVER the limits.

Its actually akin to running a RB26 to say 7500rpm out of 8000rpm. Why?

Because that’s WITHIN the limits.

Notice a the theme of within the limits and therefore reliable? I do, as do the countless others making over 300rwkw. Safely.

330rwkw out of GT-SS's is not over the limits, and is not unsafe. Fact.

[R33GTRKid]

well next time someone from over east can tune a perfectly good strong RB26 with all the necessary mods and GTSS's flies over here, ill pay for the dyno and a few hours of their time (I know it is on holidays time) to get me 330 SAFE RWKW on my GTR and then ill eat my f**king keyboard

[NXTIME]

I'm surprised that no one has brought this up yet:

http://www.skylinesaustralia.com/forums/Fs...ss-t236753.html

[Swiper the Fox]

well next time someone from over east can tune a perfectly good strong RB26 with all the necessary mods and GTSS's flies over here, ill pay for the dyno and a few hours of their time (I know it is on holidays time) to get me 330 SAFE RWKW on my GTR and then ill eat my f**king keyboard

airfare's and accom. included ?

[Roy]

well next time someone from over east can tune a perfectly good strong RB26 with all the necessary mods and GTSS's flies over here, ill pay for the dyno and a few hours of their time (I know it is on holidays time) to get me 330 SAFE RWKW on my GTR and then ill eat my f**king keyboard

I know of 3 examples all from different tuners from two different states

[R33GTRKid]

JOhnny I have 283 RWKW from my SS's (-9's) and if that is all you are after, they should be what you get because there is no lag at all and at 4,000 rpm the car takes off and pulls to 6,500 but then seems to not keep pulling harder and harder which is what I want and which is why i need 2530 (-5s) but if you are only seeking the 250 to 270 quoted the (7's or 9's) should do it awesomely:

FYI only

Dyno1.pdf

dyno2.pdf

haha the line on the boost that does NOT taper off but stays at 17 psi is my hand writing trying to ask why my boost will not stay on that line! the GTSS kit came with the HKS heavy duty actuators so I cant figure out why it is doing it, must be something to do with the EVC6 settings. Even if I set my boost to 18psi I have not seen more than 17.2 although I have not been hard on anything more than 3rd gear (cos I do not want to lose my license and am waiting to go to the drags next week)

Paul... nice try, but not made of money, if you or Ben from Racepace or anyone else that knows anything about getting 330 SAFE rwkw from a GTSS set up on a stock bottom end 26 comes to WA, ill politely interrupt your holiday for a few hours and fill you up with beer, wine, soft drink and food and take you out for the night

Edited January 29, 2009 by R33GTRKid

[R33GTRKid]

I know of 3 examples all from different tuners from two different states

get them to fly over to Perth then and use my car and x-speed's dyno, i have my knife and fork ready and I have my salt and pepper out to season my keyboard

[Johnny]

JOhnny I have 283 RWKW from my SS's (-9's) and if that is all you are after, they should be what you get because there is no lag at all and at 4,000 rpm the car takes off and pulls to 6,500 but then seems to not keep pulling harder and harder which is what I want and which is why i need 2530 (-5s) but if you are only seeking the 250 to 270 quoted the (7's or 9's) should do it awesomely:

FYI only

Dyno1.pdf

dyno2.pdf

haha the line on the boost that does NOT taper off but stays at 17 psi is my hand writing trying to ask why my boost will not stay on that line! the GTSS kit came with the HKS heavy duty actuators so I cant figure out why it is doing it, must be something to do with the EVC6 settings. Even if I set my boost to 18psi I have not seen more than 17.2 although I have not been hard on anything more than 3rd gear (cos I do not want to lose my license and am waiting to go to the drags next week)

Thanks for the info mate, appreciate it!

A little while ago, i wanted more like 300awkw but ive lost the whole power hungry phase and my current tune feels great @255awkw on stock turbines, i dont really redline the car; more like 4000-5000rpm max so yeah looks like -7 is my choice!

definitely will be adding cam gears and a better front pipe; keeping stock dumps! also will change the intercooler or might just get it internally cleaned as i know oil buildup can affect heat exchange very much.

ill be surfing through the threads on meth injection!

[R31Nismoid]

I'm surprised that no one has brought this up yet:

http://www.skylinesaustralia.com/forums/Fs...ss-t236753.html

Cant argue with 127mph either

[PHA71L]

hard to say to it is tuned.... its making boost from around 4000 or so but puts you back around 5000

all ready pulls harder top end

and pulls all the way to say 7700 can not feel it drop off at all but not driving it to hard till its tuned.

thats on 14psi act boost as well....

more boost and a tune i say it will be pretty fast with alot more top top end!

but feels like it will miss out abit in 1st gear

my stockers would spin the tyres coming on boost in 1st gear but yeah tune will tell!

afm will let me down i would think? but should go around 300rwkw?

we are happy to run up to 20psi pump fuel but yeah see how it goes with the afm for now and how much boost we can get out of it... will still be a safe tune....

[R31Nismoid]

^^ 20psi on pulp should see 360rwkw-390rwkw depending on the build of the motor.

AFM's you can tune past, not the best thing to do but by all means can be done.

On 14psi it should be pretty close to 300rwkw as it is.

Im making 250rwkw on 12psi from the SS's so near on 1 bar with -5s will feel a bit lazy, once you see 20psi you'll really wake it up.

If your stock turbos spin the tyres then you need better ones

Im RWD and i barely turn the tyres with two wheels unless i do a silly launch, and you've got two more rubber items than i have doing the work!

[PHA71L]

you just need a real tune haha i had 262rwkw on 13psi stock turbos....

it would spin the tyres by just putting your foot down in 2nd gear come on boost and spin them up in rwd that is

[some_cs_student]

Interesting discussion, as I hinted at in the E85 sticky I'm curious how the argument would change if you were planning to use E85 fuel.

You will get a more power out because of better ignition timing, but I'm not sure what happens turbo-wise, I *think* that it would make a -7 / -9 or GTSS more attractive then the -5 because you can get a large power level without going for the larger turbo.***

*** Assuming you like response, if you want the hard rush of power at 5K RPM or similar then buy a large turbo

[JAGR33]

well all I can say is that one of the most experienced tuners in WA disagrees with you Nismoid and I have spoken with three other shops over here and had the same response that 400rwhp is about max for GTSS's but you obviously must know better.

Oh and HKS rate the GTSS at 280hp each which makes them 560 combined!

Yes I have read the rb26 dyno post, I have posted in it. I have also posted up my dyno results after expecting the world (you were one of the pro GTSS's) from the GTSS's, spending a shit load of money and only getting 390 rwhp and asking for help as to what could be the issue to cause a lower than expected (after listening to you and others in the rb26 dyno thread). I got 2 replies, maybe you could have a look over them and shed some of your allknowing light into the thread, if you search dyno result posted by my username it should come right up.

What all three workshops over here have said is that dont listen to all these blokes quoting higher than 400 rwhp figures on dynos that are likely to be out by at least 10%.

250rwkw at 12 psi is not unusual, it is 350hp which is what I am also getting at about 12 psi, it is just after that you are not getting much more and they are just too small to hold much more than 15psi through the higher rev ranges (or at least that is what I have been told x 3 by x 3 different workshops here). I did say anything more than 400rwhp and you have to run 20 psi plus which is out of their efficiency range - I dont know if I would be putting 22psi through GTSS's (which will be running pretty damn hot) over a stock RB26 bottom end, which is where I was talking about it being dangerous.

At the end of the day, all I can go on is my experience with my car and my mods which is what I said I was referring to along with three of the most reputable (including possible the most) rb26 tuners in WA saying the same thing. 400rwhp is approx max for a safe tune on a RB26 running GTSS'.

I wish I had gone the 2530's (-5's) because I would not be still waiting for the top end rush that does not come with the GTSS's, yes they are fun to drive, yes they are very responsive on the street, yes they are fun on the track also, but they do not give me the punch I was hoping for and certainly no where near the 330rwkw everyone else is talking about.

2 over here have tuned it now and I am going to try a third next week to see if we can go any further. Both so far have performed leakdown and compression tests and they came back perfect. You say my supporting mods are unnecessary, I call them insurance to allow the motor to perform with less stress but still no 330rwkw, in fact I am not even on 300 rwkw but you know best!@

There's nothing unusual with the results you are achieving, if I understand correctly you are getting 270rwks on 15psi with a safe tune with your -7s on a standard bottom end.

I don't see what the fuss is all about.

It's very rare you'll see 330rwkws with GTSS's/-7s, not on a standard motor anyway, same as getting 380rwkw with -5's.

I'd say 300-310rwks for -7's and 340-350rwkws for -5's is more realistic (both using min. 20 psi)

Now to get back on topic i'd recommend the -5's, seems like your more interested in the big rush rather than responsive linear power that runs out of puff up top...

[_Ryan_]

i may not own an rb26 but if i was making the choice i would go for the best response on a street car, its not like you cant change gear when it runs out of puff, you will run out of points before you run out of gears...

[JAGR33]

i may not own an rb26 but if i was making the choice i would go for the best response on a street car, its not like you cant change gear when it runs out of puff, you will run out of points before you run out of gears...

I agree, but you could lose your license in a standard GT-R aswell, doesn't take much does it.....

[Angus Smart]

it would spin the tyres by just putting your foot down in 2nd gear come on boost and spin them up in rwd that is

i could do that in 3rd with busted n1's on the freeway doing 90-100km's tho i was running 1.7-1.8 bar... good times!

[PHA71L]

haha thats hard!!!!!

i went the 5s because if i wanted more power, which you allways do! so i had head room for more

they all ready feel like they will not run out of puff and thats untuned on 14psi

can not wait till next friday to get it tuned!

my afm are going to let me down but least ill get a taste of what these turbos can do

[Adz2332]

take it from me as gospel, PLEASE GO THE 5's PLEASE.

I was umming and ahhhing and was told to go the SS's and they would be good for 450 rwhp

BUULLLLLLLLLLSSSSSHHHHHHHHIIIIIIIIIIITTTTTTTT

any more than 400 rwhp (on a proper dynodynamics not a hub dyno!!) and the GTSS's are out of their efficiency range and you are having to run 20 plus PSI.

I have all the supporting mods, cams, dumps, full turbo back exhaust (Mines stainless front pro, decat and kakimoto mega N1 rear), tomei manifolds, evc, djetro, Sard 700's, HKS fuel pump and AFR etc etc etc and 400 rwhp on x-speed's dyno is about it. My motor is new as too.

GO THE 5's, the lag??? psssttt you are talking about 500 rpm MAX, my SS's hit full boost by 4,000 rpm, the 5's would be on by 4,500 max and probably still pushing more power at 4,000 even at a lower boost, so go the 5's. A decent tuner will be able to minimise lag by properly dialing in the cams anyway.

All this bullshit about SS's are good for 330rwkw (465 hp) is just that IMHO and if you got that much out of them it would be a time bomb. The only way to truly tell is to put all turbos on the same dyno under the same conditions but I doubt very much a true reading dyno would show anywhere over 300rwkw for the SS's.

GO THE 5's, otherwise, buy the 5's, ill swap you my 500km old SS's and give you $500

lol id probably take you up on that offer!!