Attn: Freebaggin or others

[Freebaggin]

freebaggin: what injectors are you using?

how much did they cost?

Sard 550cc/min. I got them for a special price but I generally bank on about $1000 from Greenline:

http://www.greenline.jp/catalogue/bcpartli...ntake=FI#engine

or Nengun.

If unlucky might also have to pay for import duty, extra $300??

[4door_Sleeper]

gobiz - I cant remember exactly so perhaps he (or others who know) could correct me here. I believe he ended up with near 300rwkw after all modifications including - lots of head work, bump pipe and screemer pipe, rebuilt block (cant remember the specs) and his hybrid turbo.

Anyone else know any more or can correct my figures??

[whatsisname]

rbs13,

Yep mate my turbo uses a VL style T3 exh housing, I think Freebaggin's uses the same VL T3 style housing too? I'd say my turbo combo wouldn't be too bad on an RB20DET. Naturally it'd be laggier. You'd certainly have boost by 3500-4000 though.

On the dyno, thanks to a leaking BOV, I've "only" used ~1.35bar. I have ran as high as 1.7bar (not record any dyno numbers on this much boost though) The latest drag passes were using 1.35-1.38bar

4door,

No mate my turbo uses the VLT T3 ext housing (as per above) with a Garrett core and T04E housing. It was built by Precision Turbochargers to a Vince Rigoli spec.

Yeah I don't know how Matt's and my turbo were like compared to each other. Pity he wasn't still in Adelaide when we had the SA SAU dyno day a month or so back!

I haven't heard how his new engine went power wise? By the sounds of things quite well (300rwkw) !

[Sydneykid]

Hi guys, sorry it took me a while to get around to this thread....

Overdriving injectors 10% in flow has had no bad effects that I have experienced. Some people do it 30% and don’t have a problem. I asked a Bosch engineer if 10% was OK and he said that would be no problem with their injectors. But it is relevant to how much boost you run. Remember you are running a base pressure that is 25% (to achieve a 10% increase in flow) over standard may not be a problem at 1.2 bar.

Injectors are usually rated at around 70 psi

Standard = Base pressure 38 psi + boost 12 psi = 50 psi

You have 20 psi capacity left.

Modified = base pressure 47 psi (+25%) + boost 18 psi (1.2 bar) = 65 psi

Leaving 5 psi capacity

But if you turn the boost up to 22 psi (1.5 bar) you have no capacity left and the injectors may leak and/or have poor spray patterns at that pressure. It is the total pressure that matters not the base pressure.

So I think quite a few people link injectors capacity directly to horsepower, like 370 cc = 370 bhp = 225 rwkw. This is not a bad rule of thumb. Then I say +10% is OK, so there is a presumption that 250 rwkw (225 + 10%) is OK on standard injectors. But the reality is it's not OK if the boost (needed to make 250 rwkw) is high enough to require you to exceed the pressure control limit of the injector.

The next issue is rpm, as the rpm rises the injector has less time stay open (and flow fuel). So this reduces the effective capacity of the injector. Say 370 cc per minute is the rating at 7,500 rpm. If you increase the requirement from the injector to 8,500 rpm then you need a 420 cc injector to keep the same flow rate per engine rpm.

Tuning tip, turn up the pressure on the dyno to a level that supplies the engine with enough fuel. Then check the base pressure, if it is under 50 psi I always feel comfortable that the injectors can cope. If not I buy bigger injectors. The Bosch pumps are rated at 73.5 psi so they can handle it as well.

Someone earlier on said injector spray pattern/flow was the problem with broken ring lands, not tuning. I totally disagree, if the tuner knew their stuff they would recognise excessive load on the injectors as per above and tune the engine appropriately. My preferred alternative is to say to the owner, "you have reached the power limit of the injectors" + "I recommend we stop at this (safe power level) until you get a set of larger injectors".

Hope that helps

[Sydneykid]

4-door sleeper: I've sent an email to Tim, will update you.

Still haven't heard Sydneykid's, Steve's and others opinions re:this turbo.

What do you guys think?

OK gobiz, lets have a look at this piece, by piece...

1. GT30/40 internal gate Garrett hybrid

Yep, needs a spacer on the exhaust manifold to turbo flange and all the pipework (compressor inlet & outlet, turbine dump, oil and water feed) fabricated. None of the standard stuff does the job properly and the fabrication is tricky and not for the inexperienced as it is such a tight fit.

2. With conservative tune it has 253rwkW at 1.15 bar

Big deal, what's the average power from 4,500 rpm to 7,500 rpm?

3. with stock inlet and exh manifold

No problems with the inlet manifold, it has at least another 50 rwkw in it.

Exhaust manifold is the issue, it's an ever increasing restriction over 220 rwkw.

4. stock throttle body

Ditto inlet manifold

5. stock cams

What's the response like?

6. no cam gears

Well you can only fit one if you want to keep the VVT. There is some max power increase from the exhaust cam timing changes, but the big improvement, if you tune it right, is in response and average power.

7. 550cc injectors

Good idea

8. Microtech

Not my favourite, see other threads (search "Sydneykid" and "Microtech").

9. FMIC."

What size? And the pipework?

I have used this spec GT3040 for 320 rwkw at 1.4 bar, the compressor is rated at 55 lbs per minute of airflow and it was externally wastegated on a fabricated manifold.

0.63 A/R Turbine Housing

0.70 A/R Compressor Housing

56 Trim Compressor Wheel

55 lbs/min Comp Flow Max

So I see no real problem with making 253 rwkw at 1.15 bar, but there are other issues. The main thing is how fast is it? If it has lousy average power over the used rpm range, it will be slow. And how "nice" is it to drive? Personally I hate driving a Skyline that doesn't run nice all the time and respond when I put my foot down.

So more info is required, before I can give a "real" opinion.

[whatsisname]

6. Cam gears - the standard NVCS "inlet" gear can be adjusted anyway.

I'm sure a few people have already had a look at this dyno sheet but below is the back-to-back comparison (same dyno, same day) btw a GT3040 (internal gate) a HKS GT2835ProS, HKS GT3037S and my bitza T3/T4:

Freebaggin - GT3040

Grepin - HKS GT2835ProS

whatsisname - T3/T4

Steve - HKS 3037S

[Sydneykid]

Hi Matt, are these runs in 3rd gear?

[Freebaggin]

Other things to consider:

Whatsisname - boost 1.4 bar? Nice aggressive tuning due to lower comp & forged pistons

Grepin - 1.3 bar, fabricated tubular exh manifold, 85mm throttle body, Greddy plenum, 90mm thick FMIC

Steve - 1.4 bar?? HKS 256/264 cams, 0.87 exh A/R, exh wastegate, tubular exh man, lower comp via head gasket (more aggressive tuning?), cam gears, Greddy plenum

Interesting numbers relative to mods.

SK, all done in fourth gear.

Turbo doesn't need spacer due to 0.6 A/R comp housing.

FMIC 75mm X 300mm X 480mm, 2.5" pipework I think (i've seen much bigger on Tilbrook cars for eg)

Car is faster, but doey under 3000rpm, power band is smaller than before however but car faster overall for sure.

Very happy with Microtech personally.

Next step for me is Tomie Poncam as per SK suggestions and tubular exh manifold, I hope for 15% power increase in mid range and maybe 10% up top. Should get nicer spread of torque/power.

Also check pressure drops associated with pipework and FMIC.

[whatsisname]

No mate, 4th.

[whatsisname]

Lach,

I had ~1.35bar on board for the power run above. It was limited by the leaking BOV , even after we tightened the crap out of it. My tune isn't too aggressive, total timing is only 2 degrees above stock.

EDIT: Oops... forgot to add... I couldn't agree more with Freebaggin re the Microtech LT12. I'm absolutely amazed at how well it runs my car!

I love the LT12 and the options it gives me. To be totally honest I was expect it to be a POS given the bagging people seem to give Microtech, boy was I wrong!

Maybe I'm a tad selfish, but I hope people continue to bag Microtech, that way they'll keep the prices down and work hard to make as many low cost features and upgrades as possible

[EnricoPalazzo]

Boost still hasnt had a proper tune yet since doing all the rebuilding. hes hoping for 300rwkws.

[Cubes]

Freebaggin,

I hope you know I'm keeping a close eye on how well your internal gated turbo goes.

What sort of boost are u running?

The other week I think I saw you pulling up at a set of lights down south (u were turning right). I saw you do the finger wave on the steering wheel but I was in a bit of a daze. ?!? was u?

[Freebaggin]

Freebaggin,

 

I hope you know I'm keeping a close eye on how well your internal gated turbo goes.

 

What sort of boost are u running?

 

The other week I think I saw you pulling up at a set of lights down south (u were turning right). I saw you do the finger wave on the steering wheel but I was in a bit of a daze. ?!? was u?

Wasn't me mate, don't work down south anymore.

I run from 0.7 to 1.2 bar, which is 215-265rwkW peak power. Being internal gate also helps with cops I think re defecting.

For you, I'd see if I can get the same ext housing as used on the XR6T. I called Garrett once and from memory they'll sell you one. It's 1.06 A/R and has same design as the nice ProS HKS internal gate turbos. A/R too big for 2.5L when combined with the compressor size on GT3040, but tor a 3L motor it would be perfect :burnout:

[Cubes]

Tim said he can machine a VG30 .81 or .83 not sure exactly exhaust housing and bolt that on. He said it wouldn't be warranted but I think it may work quite well.

[Sydneykid]

No mate, 4th.

Hi guys, would I be right in saying that (at 27 kph per 1,000 rpm) all of them are running out of breath at 6,666 rpm (180 kph). Most have topped out their power by 5,925 rpm (160 kph).

How about that, despite the differences in mods and tune, all the cars have ~75 rwkw at 80 kph.

Average power looks like;

RPM--------KPH--------Steve----What-------Grepin-----Free

6,667------180--------275--------265--------270--------255

5,926------160--------295--------280--------265--------265

5,185------140--------290--------265--------240--------230

4,444------120--------255--------230--------210--------215

3,704------100--------115--------150--------165--------120

Average---------------246--------238---------230--------217

Very interesting.

[Freebaggin]

Hi guys, would I be right in saying that (at 27 kph per 1,000 rpm) all of them are running out of breath at 6,666 rpm (180 kph).   Most have topped out their power by 5,925 rpm (160 kph).

How about that, despite the differences in mods and tune, all the cars have ~75 rwkw at 80 kph.

Average power looks like;

RPM--------KPH--------Steve----What-------Grepin-----Free

     

6,667------180--------275--------265--------270--------255

5,926------160--------295--------280--------265--------265

5,185------140--------290--------265--------240--------230

4,444------120--------255--------230--------210--------215

3,704------100--------115--------150--------165--------120

     

Average---------------246--------238---------230--------217

     

Very interesting.

Good stuff SK, wierd than all have power drop off at high RPM (peak power below 6000rpm) except Grepin but then again, Steve's threshhold is alot higher with ~300rwkW, so a v.good result really.

Don't want to give excuses but I forgot I had my boost controller safety set a tad low (didn't realise until after!) and when 100% throttle from 2000rpm, when turbo cut in the thing was spiking back to 0.7bar from 1.2bar so the runs were done with easy ramp up. Previous dyno runs done at on same dyno at 1.2b, the boost curve is a tad better with a bit more power from 3500rpm.

I'll redo from previous run at 1.2bar:

RPM--------KPH---Steve (1.4b?)-What(1.35b)-Grepin(1.3b)-Free(1.2b)

6,667------180--------275--------265--------270--------255

5,926------160--------295--------280--------265--------265

5,185------140--------290--------265--------240--------236

4,444------120--------255--------230--------210--------216

3,704------100--------115--------150--------165--------126

Average---------------246--------238---------230-------220

Well, not much difference really, however with with EBC safety reset and boost upped to 1.3 bar (+octane booster) from 1.2bar I reckon it will get some nicer ave numbers.

[Freebaggin]

For what it's worth, here is my prediction of the incremental increase in power when I add on the Tomei PONCAMS and nicer tubular exhaust manifold.

More mid-range from cams.

More top-end from exh manifold.

What do ya think?

[gobiz]

Wow, those are some nice curves freebaggin. :boobies2:

I contacted Tim at HPIAbox bout your turbo, I'm afraid I won't be able to afford his price.(exchange rate very poor for me at the mo)

On the up side, I found a local turbo engineering place.

He quoted a very good price for this T3/T4 hybrid:

Compressor housing a/r .70, wheel 56mm

Turbine housing a/r .84, wheel 58mm

It's internal gated and I know it's not BB, but I don't mind.

He said it's rated at 500hp.

What do you think? :sadam:

[gobiz]

Anyone know what turbo is comparable to this one (specs above)?