-7/9s Or -5s Garretts

[discopotato03]

I'll offer my parting thoughts and call it a day .

I see people say I get full boost at so and so revs and its like they think they have to be at the regulated pressure setting to go well . I reckon the important things in a road car are do I get reasonable part throttle boost/torque and will the engine pull when I want it to . I believe if you have to have the throttles fully open to have any worthwhile squirt then the state of tune is too high for the street .

IMO the aim is to have useful torque using the turbos to shove a useful amount of air into the engine to achieve it .

From a challenge point of view its a shame I'll never have a GTR because it would have been interesting trying to get a more Evo like power curve into say an R32 . I know enough from having a 25T that Skylines have a bit of a front heavy feel about them and from drivers who drive them that GTRs feel it even more so .

I doubt I could get one to feel and drive nicely for me without it being striped out like a racer and who wants to drive a tool shed around .

Most of you would think I was mad but I'd have tried the R34 BB turbos and done head work and shortish high lift cams .

Higher static CR and spent time getting the tuning right . -9/GTSS turbos would be the largest I'd have put on a full weight std capacity GTR because even they are more than good enough for street performance IMO .

Anyway subjective because I don't aim to have one .

Cheers A .

[BoostedBarge]

You raise a good point there... Anyone have much experience with R34 BB turbos? A mate of mine got a set rebuilt with steel wheels. He was adamant that they would be far more responsive that a set of SS's and should give close to 300rwkw which is ample for the street. The bugger is that he left the country and locked his car up 2 years ago, so it's never seen a dyno to prove how well the R34 BB turbos perform. I'd love to see some results of a set running some decent boost.

I'm thinking for my heavy Stagea, they might be a better choice for the street.

[R31Nismoid]

Totally depends WHAT wheels are actually used.

For 300rwkw, that is basically Garrett -7s (in terms of wheels required)... In which case you'd just get -9s in the end anyway

Steel wheels stockers, with the same size wheels, would be around 280rwkw max IMO. But it's such a close area to fill most combo's are within a few hundred RPM from 270-320rwkw.

I love my GT-SS's currently in a 1400kg car (no driver) & 4.4 gears, makes a big difference and i only have 280rwkw with them rather than the extra 50rwkw or so.

[Nee-san]

Totally depends WHAT wheels are actually used.

For 300rwkw, that is basically Garrett -7s (in terms of wheels required)... In which case you'd just get -9s in the end anyway

Steel wheels stockers, with the same size wheels, would be around 280rwkw max IMO. But it's such a close area to fill most combo's are within a few hundred RPM from 270-320rwkw.

I love my GT-SS's currently in a 1400kg car (no driver) & 4.4 gears, makes a big difference and i only have 280rwkw with them rather than the extra 50rwkw or so.

I have Driven a car (32 GT-R) with headwork and GT-SS making around 300AWKW and the thing is a monster, through the mountains it allows you to pull idiotic speeds even through the shorter sections...

Slightly off topic, I see that Garrett rates the -9 at 310HP per unit but it surprises me more people, especially those with forged bottom ends arent pushing the 350KW mark.

I know that Giant on here made 400kw on similar size turbo's admittedly with race fuel but race fuel isn't worth 100kw.

It's very interesting to see the different results people are getting with these turbos.

[Nee-san]

I have Driven a car (32 GT-R) with headwork and GT-SS making around 300AWKW and the thing is a monster, through the mountains it allows you to pull idiotic speeds even through the shorter sections...

Slightly off topic, I see that Garrett rates the -9 at 310HP per unit but it surprises me more people, especially those with forged bottom ends arent pushing the 350KW mark.

I know that Giant on here made 400kw on similar size turbo's admittedly with race fuel but race fuel isn't worth 100kw.

It's very interesting to see the different results people are getting with these turbos.

Guise ?

[SideOn]

For comparison sake this is my dyno of my r32 GTR that has everything you can possibly do to an unopened motor.

HKS everything exhaust/ic/dumps/catback/4.5inch cat. PFC, 700cc INJ's, nismo afms blah blah blah. >> Blitz Electronic EBC. (used tap on dyno)

I personally find my setup laggy even tho it seems to make marginally better power @ certain rpms

than other peoples setups with GTSS's / -9's (compared to dyno thread).

Running HKS 2510's. The car feels as tho it can rev to 10,000rpm. Power REALLY comes on @4500-5000rpmish.

aslong as your doing 60km/h-70km you may enter WARP speed very easily. and then suddenly your spastically breaking the speedlimit.

obviously this all sounds pretty awesome but i kind of miss the downlow response of stocks?

Comparing 2510s / GTSS's vs STOCKS... people say they are no laggier than stock... DUH on stock BOOST ofcourse NOT!

but when you put them to 1.3-1.4 BAR it seems as tho the motor cant flow enough to handle the extra boost lol.

I am considering getting cam gears altho im unsure whether this will make the car more responsive.

any suggestions without hauling lots more $$$?? btw my tune is a rich tune.

could just be my expectation or another bottleneck in my system....

Edited August 4, 2010 by SideOn

[Nee-san]

For comparison sake this is my dyno of my r32 GTR that has everything you can possibly do to an unopened motor.

HKS everything exhaust/ic/dumps/catback/4.5inch cat. PFC, 700cc INJ's, nismo afms blah blah blah. >> Blitz Electronic EBC. (used tap on dyno)

I personally find my setup laggy even tho it seems to make marginally better power @ certain rpms

than other peoples setups with GTSS's / -9's (compared to dyno thread).

Running HKS 2510's. The car feels as tho it can rev to 10,000rpm. Power REALLY comes on @4500-5000rpmish.

aslong as your doing 60km/h-70km you may enter WARP speed very easily. and then suddenly your spastically breaking the speedlimit.

obviously this all sounds pretty awesome but i kind of miss the downlow response of stocks?

Comparing 2510s / GTSS's vs STOCKS... people say they are no laggier than stock... DUH on stock BOOST ofcourse NOT!

but when you put them to 1.3-1.4 BAR it seems as tho the motor cant flow enough to handle the extra boost lol.

I am considering getting cam gears altho im unsure whether this will make the car more responsive.

any suggestions without hauling lots more $$?? btw my tune is a rich tune.

could just be my expectation or another bottleneck in my system....

Try different turbo's is all I can suggest, I know that GT-SS are awesome for response from first hand experience. (Not my car, I have 33 N1's)

[R31Nismoid]

For comparison sake this is my dyno of my r32 GTR that has everything you can possibly do to an unopened motor.

I am considering getting cam gears altho im unsure whether this will make the car more responsive.

Well clearly you do not have "everything you can possibly do"

Cam gears are the single best value item you can add to a RB26 IMO. Factory turbos or 400rwkw worth of turbo, they always come in handy.

There are excellent gains for the couple hundred they cost. You are crazy to not have done them yet.

Plenty of threads around with the results from a bit of cam gear setting. Every car is different so it'll require some dyno work to find the 'sweet spot'.

[scotty nm35]

Also, if you do have a rich tune, the turbos may not come on as well due to the acceleration enrichment. I had a lot of issues with stomping on the pedal and going nowhere untill 3k but now it spins up freely after taking 15 percent out of it. Very hard to adjust on the dyno as the wideband doesn't pick it up. Im sure a good tuner could find extra response in any map given enough time.

[Nee-san]

Well clearly you do not have "everything you can possibly do"

Cam gears are the single best value item you can add to a RB26 IMO. Factory turbos or 400rwkw worth of turbo, they always come in handy.

There are excellent gains for the couple hundred they cost. You are crazy to not have done them yet.

Plenty of threads around with the results from a bit of cam gear setting. Every car is different so it'll require some dyno work to find the 'sweet spot'.

Word.

Also, what cams are you running ?

Edited August 5, 2010 by Nee-san

[SideOn]

Word.

Also, what cams are you running ?

Stock Cams, I didnt want to spend another 2.5-3k lol.

But yeah cam gears + another retune might fix the mini lag dilemma

[Deano 1]

362 is awsome from -9's.

[Nee-san]

Stock Cams, I didnt want to spend another 2.5-3k lol.

But yeah cam gears + another retune might fix the mini lag dilemma

Yeah mate, dont throw the baby out with the bathwater, have them looked at first and go from there.

And yes, 362 is a very nice figure, it would be interesting to know the details of the build.

[R31Nismoid]

Word.

Also, what cams are you running ?

Me?

Im factory.

[pistol-pete]

Stock Cams, I didnt want to spend another 2.5-3k lol.

eh? about 1k will see you with some Tomei Type B Poncams, take like an hour to put in.

[EdGTR]

Hi all i think i can post here now that i just fitted a set of GT-SS's to my 32 after the rear stock one filled the pistons up with ceramic. For those who say it cant happen ill show you a piston with bits of the ceramic still stuck in it.

I bought a front cut and put all my externals on and a set of new SS's, Tomei dumps and a tomei fuel pump for a little piece of mind.

Previously i was running stock turbos with the restrictor removed so i put the restrictor back in until i can get it on a dyno. I did some road tuning of my PFC with my wide band (ie rich as) but my initial thoughts are very good. Its seeing full boost of 12.5 ish before 3 grand and pulls hard all the way up top. My plan is to fit a y pipe and cat and then put it on the dyno so ill post my graph when i can, I chose the SS's because i want very good response and about 280kw and for it to be very safe for a standard bottom end. It will see the track and for me it will be enough. There is enough money to be spent on tires, brakes and suspension to keep me poor.

[iplen]

-7s on and being driven, comes on slower but about the same revs, then gets better and better! Car actually handles better, less taily because of the more gradual delivery. Most importantly 2psi less and HEAPS faster!!!

[R.3.2.G.T.R]

Nismoid is stating cam gears not cams, less than $500 for jap ones but very worthwhile for rb26s

[Nee-san]

Me?

Im factory.

I know your Factory I meant the OP sorry mate

[Rolls]

Wonder if you can get electric cam gears, map them to load points in the tune. Now that would allow for some very good gains. Basically be an aftermarket VCT/VVTi

Only problem is you'd probably need a motec to tune it effectively.

Edited August 5, 2010 by Rolls