R33 Sii - My Gt30 Upgrade Is Done. Lots Of Pics

[The Mafia]

3rd gear is what concerns me, and its coming on at 4500rpm... thats pretty bad you know

Edited December 27, 2005 by The Mafia

[Cubes]

That is definitely bad.. Imagine second :S

Maybe its got a little to do with the tune?

[The Mafia]

second is 15psi at 5000rpm

Tried tuning it differently made no difference

[Cubes]

They may have stuffed the machining of the turbine housing?

[The Mafia]

well something is stuffed to be making that much lag with a supposedly small exhaust housing

[discopotato03]

Craig of Allen Engineering in Mallala once explained to me why overbored turbine housings don't work . The explanation was that once its bored for a larger OD turbine the side of the internal passage facing the blade tips opens up . What happens then is the gasses enter the blades at a different angle than the one intended by the original turbines designer .

That example of 20lbs boost at 3200 rpm sounds weird , I'd be real curious to know what it makes at 2000 and what was done to control detonation - what full load ignition timing does it run between 2-4000rpm .

Cubes if you were running with integral gates fixed open and generating boost then clearly the gas flow capacity of the exhaust housing is too low . The fact that those Hitachi's all used the same sized turbine indicates that it was a manufacturers compromise and not intended for super performance duty . Even with a large a/r housing (VG30) the turbine inlet pressure can be manageable , the short blades (small dia ceramic turbine) can only make so much shaft power . Its always a trade off between shaft power and resistance to gas flow . The adequate sized compressor will not overtax the turbine (power supply) nor push excessive air into the engine creating unmanageable volumes of exhaust gas which the turbine housing may not be able to cope with .

Cheers A .

[discopotato03]

48 , 52 , 56 Trim TSO4 Maps - the real ones . The last one is the GT30R's 76mm 56 Trim GT37 compressor from cartridge no 700382-12 . It lives in the real GT30R and the HKS GT3037 56 Trim .

Cheers A .

Edited December 27, 2005 by discopotato03

[Cubes]

A little off topic..

Disco here's the dyno run I did with it wired open.

Basically starts making some boost straight away.

Note the R&R using the stock ecu with the rb30det.

I also have an afr print out.

Edited December 3, 2008 by Cubes

[BHDave]

That example of 20lbs boost at 3200 rpm sounds weird , I'd be real curious to know what it makes at 2000 and what was done to control detonation - what full load ignition timing does it run between 2-4000rpm .

<{POST_SNAPBACK}>

Whats so weird about it? You've said yourself that the 7 blade wheel is more efficient at lower speeds than the 6 blade wheel and we are seeing those turbos making similar boost not much further up the rev range. Combine it with a decent manifold and a .63 turbine housing and you have a turbo that is starting to spin pretty quickly at low revs and make some positive pressure.

What it makes at 2000 in terms of boost or power? boost, a couple of psi if it's in a high gear, nothing in lower gears. Power, probably a bit below 60rwkw, my dyno sheet doesn't go that low

Control of detonation? That would be a decent tune with decent fuel by a decent tuner. In this case Ultimate and tuned by unigroup. Peak knock on the hand controller around 33-36, a bit higher (with the occasional excursion above 60)when using optimax or Caltex shit. Typical bolt on's, fairly big oil cooler as the turbo isn't water cooled, and a relatively small 400x300x60 tube and fin frontmount intercooler.

Full load ignition, see the attached section of my ignition map. Actually, the forums won't let me upload an excel sheet. Basically L13-L18 between 2800 and 4000 range between an average of 17 degrees at L13 down to an average of 8 at L18. Minimal tuning has been carried out below this point as the car doesn't get there, it drops to 6. Peak afm voltage of about 4.8V though thats a little further up the rev range. It's a z32 afm.

And it's 21 psi by 3200.

We seem to be getting a little off topic. Mafia, whats your time frame on getting the rb exhaust housing on? Despite disco's disapproval of my suggestion to run a machined rb housing i think it is worthwhile to spend $100 now as an experiment rather than throwing your hands in the air and spending another 1400 on a new cartridge that may or may not work properly with your existing VG exhaust housing.

[paulr33]

so even with the gate open it still made 6.5psi

[The Mafia]

Whats so weird about it? You've said yourself that the 7 blade wheel is more efficient at lower speeds than the 6 blade wheel and we are seeing those turbos making similar boost not much further up the rev range. Combine it with a decent manifold and a .63 turbine housing and you have a turbo that is starting to spin pretty quickly at low revs and make some positive pressure.

What it makes at 2000 in terms of boost or power? boost, a couple of psi if it's in a high gear, nothing in lower gears. Power, probably a bit below 60rwkw, my dyno sheet doesn't go that low

Control of detonation? That would be a decent tune with decent fuel by a decent tuner. In this case Ultimate and tuned by unigroup. Peak knock on the hand controller around 33-36, a bit higher (with the occasional excursion above 60)when using optimax or Caltex shit. Typical bolt on's, fairly big oil cooler as the turbo isn't water cooled, and a relatively small 400x300x60 tube and fin frontmount intercooler.

Full load ignition, see the attached section of my ignition map. Actually, the forums won't let me upload an excel sheet. Basically L13-L18 between 2800 and 4000 range between an average of 17 degrees at L13 down to an average of 8 at L18. Minimal tuning has been carried out below this point as the car doesn't get there, it drops to 6. Peak afm voltage of about 4.8V though thats a little further up the rev range. It's a z32 afm.

And it's 21 psi by 3200.

We seem to be getting a little off topic. Mafia, whats your time frame on getting the rb exhaust housing on? Despite disco's disapproval of my suggestion to run a machined rb housing i think it is worthwhile to spend $100 now as an experiment rather than throwing your hands in the air and spending another 1400 on a new cartridge that may or may not work properly with your existing VG exhaust housing.

<{POST_SNAPBACK}>

thanks for the explanation. NOt sure about a time frame, will call the turbo place tomorrow and see if they are open. If not, it won't be until th new year. Its not a going to be a big job, thank god lol.

[discopotato03]

BHDave I'm only offering my views . What I said was the compressor with the lower number of blades will draw less air for a given shaft speed . This is desirable because at low engine speed the engine doesn't want/need too much shoved down its throat . Ideally you want the engine and the compressor to to accelerate in step so the compressor can maintain the desired pressure head over the rising demands of the the engine from a volume point of view . Obviously the engine has a speed range - so does the compressor .

The way I see it if you feed an engine a fair chunk of boost (like 22lbs) at that point of the rev range its probably used up more of the compressors usable rev range than the engines . So as the engine revs rise the compressopr could run out of capacity lower in the engines rev range than desirable . This makes the broad asumption that there is not very high turbine inlet pressure choking the hot side of

the engine . To recover enough exhaust gas energy to move air at that pressure(22psi) I can only wonder at the gas speed through the turbine housing and what it will be like at 6000 rpm crank . Does the boost fall off at higher revs ?

I'll quote someone we all know here as well - boost pressure is a measure of resistance to air flow not a measure of airflow itself .

Why I thought the 22 psi at 3200 rpm sounded weird was because the dynamic compression must be very high . It would be interesting to play about with boost and ignition to get the best torque at that point . From my experience when the timing gets much below about 12 on boost at lowish revs less boost and a little more advance worked for me .

Cheers A .

T300 - that's a new one on me , any details or pics ?

[BHDave]

The weird thing about the turbo response in my case is once it has more boost wound in the shape of the curve is near enough identical until it hits a wall (and valve float) and the top of the curve flattens out around the 22 psi mark. It has about 1psi gradual drop off through the range up to about 7200rpm.

Here's a couple of pics. It's an ugly lump of a thing. I dont have a shot of the turbine wheel. It was sold to me as a t300s, plain bearing, not water cooled. The t04e that was originally part of the kit was junk (seized) so i grabbed this one instead and had to chop off the bend. It was a bit of a punt that seems to have paid off.

[discopotato03]

Looks like a TO4S compressor side (7 blade wheel with cast iron backplate) . Turbine side looks like TO4 turbine (74.2mm) in small A/R housing , that will drive the "S" comp better than Mafia's cropped 56.6mm GT30 turbine particularly in a native housing .

The HKS manifold and gate free's up the range of turbine housings available to you .

If anyone has the HKS RB26 cast single low mount manifold I NEED one !

Money on ice .

Cheers A .

[R31Nismoid]

This should take 3 hours, so I am looking at about a day and around the $100 mark to reduce my lag from 4500rpm to 3200 rpm. Now thats going to make the car drive 1000000000 times better.

Absolutely no adjustments will need to be made, as the flanges on the VG30 and the RB25 turbo flanges are exactly the same.

Think about it, full boost or up to 20psi at 3200rpm? Than means the car starts making power at about 2500 rpm.

Here's one last thing. I am not going to get rid of this VG30 for a damn good reason. You know why? This turbo setup doesn't belong on this block! It belongs on a RB30..... and RB30 should be able to get this VG30 setup spooling at full boost by about 3200rpm....with massive amounts of torque, and the housing should also be efficient enough to drag the RB30's arse up to 280rwkw. They are bigger than you think when ground out to fit a GT30.

You'll wanna have good fuel or its going to ping its ass off i would imagine.

I wouldnt say the VG30 is for a RB30 at all.

Very much like R31 Nismoid with his GT30R .82.

The .82 is larger than the vg30 yet its all in by 4000rpm

I was using a 600hp GT30 - .82 rear, GT40 wheel and i was on 17psi by 4200/4400rpm, with some low rpm surge which hurt the spool by a good few hundred rpm. You could see by the graph that if it wasnt surging the line would have been a bit smoother and a few hundred rpm gained.

Smaller comp wheel and my problem would have gone. In otherwords using a 550/500hp variant.

I'd say its as much to do with comp wheel as the rear end. More importantly the comp wheel.

Turbo held boost till 7500 no problem, where after that i lost all of 20rwkw and maybe 1-2psi in the latter rpm (redline 8000rpm)

Remember i also used a 100% stock RB25 head

[discopotato03]

Yep , Garrett engineers (the petrol head ones in Torrance Ca) dont like the GT3040R 56T and Garrett only market it with the largest 56 T compressor . Note the HKS spec GT3040R used a smaller 50 trim comp and .60 rather than .70 a/r comp cover/housing . These don't surge like the one Garrett sells because the map is esentially moved to the left compared to the 56 t comp . As you say the 56t GT37 76mm wheel is a better match and less likely to surge provided its not overdriven by a tiny a/r turbine housing .

This is the perfect example of how matching shaft power requirements and airflow to exhaust flow ratio gets the job done .

A little O/T but if Garrett optioned the GT3540R with a 50 t compressor and .60 a/r housing it would be more responsive too .

The bottom line is the compressor has a lot more say in how a turbo responds that many think . Compressor airflow beyond your power requirements IS NOT A FREE RIDE AND DEFINATELY DETRIMENTAL TO THE TURBOS BOOST THRESHOLD AND TRANSIENT RESPONSE . Turbine power is neither free nor limitless so wasting it to drive an air pump with surplus capacity is an exercise in futility , far better to use a compressor of adequate capacity that can utilise all the turbines power without waste . Remember every time your waste gate opens thats heat energy your wasting and you are paying for that energy at the pump .

Cheers A .

Edited December 29, 2005 by discopotato03

[RNS11Z]

here a copy of my dyno graph using a gt30 @ some 25+psi. .7 front with .82 rear.

Full boost at 4500rpm give or take

stock head & cams

the blue line is with wiseco pistons and more comp

red line arias pistons and less comp

Edited December 29, 2005 by RNS11Z

[Bl4cK32]

that power must come on like a light switch rns11z??

it goes from like 100hp to ~375 hp in 20 km/h??

Whats the average power work out to?

[ECR033]

Don't know if this helps, but I thought I'd throw in a copy of my dyno run with a GT3040R on my R33 just as a bit of a comparison...

R33 GTS25t (Standard Internals)

GCG GT3040R (0.82 exhaust housing)

Turbonetics 40mm external wastegate

HKS Cast Exhaust Manifold (low mount)

Nismo 555cc injectors

Walbro Fuel Pump

Blitz LM FMIC

Greddy Profec B Spec II EBC

Apexi Power FC

Splitfire Ignition Coils

Z32 AFM

Apexi Power Intake

3" turbo back exhaust w/hi flow cat

I also feel that this set up is too lagggy for my liking - I was hoping that boost would come on a little earlier.

I also only ran a 12.7 @ 115mph which was pretty dissapointing to be honest...I've seen others run low 12's with similar set ups which kinda indicates to me that there's a restriction somewhere (i don't think it's my driving as I did a 12.9 with the std turbo previously)

R31 Nismoid, do you have a dyno graph from your previous set up? It would be interesting to compare as well.

Good, interesting thread - hope you get it all sorted Mafia.

[R31Nismoid]

ill try grab one in the new year

should still be on my tuners dyno.

my graph was similar to yours, RNZ11's graph is very snappy, mine was far more linear making solid power early and then a nice rise to the peak

did a 12.1 in it, it was still sliding all over the shop so i'd say its your driving i did a 12.9 with 200rwkw