XTR GT3040 Max Power 206kw??????

[nv033]

As the title suggest an XTR GT3040 is making max power of 206rwkw from a 1600cc motor at 19psi of boost.....

The turbo has a 0.63 rear mounted highly on a custom locally made manifold with external gate...cams are 256 degress in and out...checked and performed all the necessary procedures eg timing etc...

AFR are 12 flat and power curve basically hits 206rwkw at 6500rpm and sits there flat to 7300rpm....when u give it more boost...it just reaches this point quicker??? i dont think this is normal is it?

Only reason being is that this is a new setup...prior to this there was a high flowed turbo making 220rwkw on 22psi :headspin:

any comments would be greatly appreciated THANX

[RS500]

hi there,

fyi, i had the same issue with my Garrett GT3040 on my 2L where it wouldn't make any decent power at about ~17-18 psi, but anything over about 21-22psi and it really woke up scaring the pants off me.

This was quite disappointing as i was intending on running lower boost to get my required power given the large compressor size.

in your case, first of all, i believe this turbo might be a little on the large side for your 1600cc engine, so you'd be better off going for something smaller, but if u prefer to stick with this coombo, then you'll need to try winding the boost up closer to 25psi as to see some decent power, as the turbo still isn't working in it's high efficiency zone (which is where it produces the air-flow for the required power level)

[nv033]

hi there,

fyi, i had the same issue with my Garrett GT3040 on my 2L where it wouldn't make any decent power at about ~17-18 psi, but anything over about 21-22psi and it really woke up scaring the pants off me.

This was quite disappointing as i was intending on running lower boost to get my required power given the large compressor size.

in your case, first of all, i believe this turbo might be a little on the large side for your 1600cc engine, so you'd be better off going for something smaller, but if u prefer to stick with this coombo, then you'll need to try winding the boost up closer to 25psi as to see some decent power, as the turbo still isn't working in it's high efficiency zone (which is where it produces the air-flow for the required power level)

motor is built to rev to 9000rpm and run 30psi of boost.....we winded it up to 22psi with no net results... i strongly feel there would be no point winding it up any more? im aware of the efficiency issues and this would be different on all motors....im happy to run 30psi and rev more to achieve the power.... i was confident that it should see 260rwkw and anything else is a bonus but im dumbfounded

[DoughBoy]

Do you know which comp + turbine wheels it has in it? By 3040, runs a GT30 turbine wheel (60mm 84 trim) and a GT40 comp wheel (can be a whole bunch of them).

The GT40 comp wheels are good for over 500hp, but that small exh housing will restrict it to about 400hp or under.

[nv033]

Do you know which comp + turbine wheels it has in it? By 3040, runs a GT30 turbine wheel (60mm 84 trim) and a GT40 comp wheel (can be a whole bunch of them).

The GT40 comp wheels are good for over 500hp, but that small exh housing will restrict it to about 400hp or under.

mate u always confuse me.... i thought all gt3040s were the same but just with different rears.....i was actually comparing this to urs.... how would i find this info...on the badge it just says XTR3040 :wassup:

[DoughBoy]

It's bad that the turbo manufacturers and distributors don't have a standard naming scheme, they are all over the place. Some name them after the inducer size on compressor, some on exducer size, some by the family (which have a million variations), some by horsepower ratings etc etc.

The one on my white car has an 82mm comp 50 trim front, 60mm 84 trim rear. GCG normally use the 82mm 56 tirim comp, 60mm 84 trim rear. The only real way to know is to measure it yourself - invoices can be wrong, wheels can be different to the i.d. tag on the catridge.. and salespeople are full of shit.

[nv033]

Edit: the .73 rear housing is restricting it to 300rwkw max, so a .63 would be even less.

were a bit off with 206rwkw arent we? im preety sure something this size would spin up more than my dirty old cantor turbo

[RS500]

nv033,

fyi, my 2L cossie has a Garrett GT3040 (A/R .63 exhaust housing) and was only making around 185rwkw on 17-18psi, which was really pissing me off as we were expecting more like ~220-230rwkw on that boost and ~250rwkw on 20psi given the specs & size of the turbo, but it wasn't the case.

So just as i had decided i had had enough and was about to pull the turbo off the car, my mate/mechanic got in touch with Geoff Watson (Garrett, NSW) and after telling him the story (i.e., specs of the engine, boost & power we were making, etc), his recommendation was that we would need about 25psi to get the power level we were after.

So under his instruction, firstly we slowly wound the boost up to 22psi first and wouldn't u know it, power jumped straight up to 247rwkw very viciously before wheel spinning on the dyno.

after some more fine tuning and a little more boost, my 2L cossie engine chalked up 265rwkw @ 4500rpm on 24psi before wheel spin problems again on the dyno.

so, maybe you need to push it a little more given that your engine is smaller than mine.

also, the GT3040 definitely has the minerals to make ~300rwkw with the .63.

[R31Nismoid]

It's bad that the turbo manufacturers and distributors don't have a standard naming scheme, they are all over the place. Some name them after the inducer size on compressor, some on exducer size, some by the family (which have a million variations), some by horsepower ratings etc etc.

The one on my white car has an 82mm comp 50 trim front, 60mm 84 trim rear. GCG normally use the 82mm 56 tirim comp, 60mm 84 trim rear. The only real way to know is to measure it yourself - invoices can be wrong, wheels can be different to the i.d. tag on the catridge.. and salespeople are full of shit.

:werd:

couldnt agree more. I'm getting mine measured when the engine rebuilt in a week or so. Measure it and you'll know for sure what you've got

[RS500]

nv033, just an idea,

is the exhaust housing an original garrett GT30 A/R .63 unit?

the reason i ask is that when i bought my turbo, it came with a non-garrett A/R .82 (split-pulse) exhaust housing and we experienced the same problem, later finding that we had a huge back pressure problem in the exhaust side which was restricting gas flow and obviously robbing power.

given this, we went back to the guys which we bought the turbo from and got them to send us the original garrett GT30 housing which made a huge difference giving us the results we have now.

before making any other decisions about the turbo, etc, it's probably worth tapping into the exhaust manifold/housing and measuring the back pressure. this should give u an indication of how the turbine is flowing the exhaust gasses.

[nv033]

nv033, just an idea,

is the exhaust housing an original garrett GT30 A/R .63 unit?

the reason i ask is that when i bought my turbo, it came with a non-garrett A/R .82 (split-pulse) exhaust housing and we experienced the same problem, later finding that we had a huge back pressure problem in the exhaust side which was restricting gas flow and obviously robbing power.

given this, we went back to the guys which we bought the turbo from and got them to send us the original garrett GT30 housing which made a huge difference giving us the results we have now.

before making any other decisions about the turbo, etc, it's probably worth tapping into the exhaust manifold/housing and measuring the back pressure.  this should give u an indication of how the turbine is flowing the exhaust gasses.

the boost controller ive been using is a dirty old turbo excess....ive notice that the wastegate spring is 4psi ..... next step is hevier spring...install of e-boost and 25psi and ill post up some results

[roz85]

sorry to hijack, but whilst we are on the conversation of large turbos i need a little help. When my 2.6 astron was dyno'd last time, the boost controller we were using had problems, and boost couldnt be increased any more than 14psi. The turbo is a hi-flowed t04 with a 1.06 a/r exhaust housing, sierra rear wheel etc. Power was 303hp atw approx 225kw atw. If what im reading is correct, large turbo's like this wont reach their efficiency till after 20psi depending on the specifics (i have no idea about the flow charts of this turbo etc)? So i should expect something around the 350hp atw mark and upwards with the turbo boosted to around 20psi?

[RS500]

nv033,

could you tell me the CHRA number of your turbo please?

this can be found on the id plate on the centre core.

[discopotato03]

RS500 , that is going on all over the world . It is absolutely critical that people use the correct turbine housing for their turbo . Too many people compromise their turbo's performance by using different or cheaper housings . Sure it has to fit your exhaust manifold but it has to have the correct nossle shape for the turbine . If you look closely at modern turbines (mainly found in BB cartriges) at the major dia the tip height or "B" width is far greater the the old T3 , T31 and in some cases to4 . It is not possible to re-create the GTBB nossle area or the volute form in T3 housings . When it is attempted the result is increased turbine inlet pressure (back pressure) , higher exhaust gas temperatures and most noticably turbo response . Do it right the first time and save on lunched pistons/valves/turbos .

RS500 I guess its personal preference but would the GT30R 56 trim have given you better response for the same turbine side .

Cheers Adrian .

[discopotato03]

Nearly forgot , in my opinion stay away from GT30XX turbos with the seven bladed (7 full and 7 spliter) TSO4 compressor wheels . They are not a true GT wheel and date back to the late 1970's . They take more shaft torque to drive than the six bladed BCI-18 wheels and the aero is not as good ie will heat the charge air more than later designs . On their compressor maps efficiency drops away over 16-17 PSIG . The seven blade versions are more common and probably cheaper but won't give the best results .

Cheers A .