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Gday,

I got my RB26 back from the engine builders yesterday, and im in the process of assembling the manifolding on both sides. I had a look at the RB26 turbo upgrade sticky thread hoping to find similar setups, but found none. Does anyone have or, know someone with, a Garrett GT35 single turbo on a built RB26 engine? Any idea what power its making?

For reference my engine has:

GT35 Turbo

38mm Tial gate

4inch exhaust

CP Pistons

Prepped rods

Standard cams

9.0:1 compression ratio

Autronic SM4

700cc injectors

Neon lights (that was a joke)

All the usual oil control stuff and a fuel system that will support it.

The car is rear wheel drive only.

I just want to make 300 to 330 rwkw on a safe tune (cant affort another engine failure). Also, i wanted good off boost drivability, hence the 9:1 comp.

Id be interested to hear peoples (informed) opinions on power output for this set up. Please, no negatives, as im still getting over the cost of this process and im feeling fragile.

Thanks,

Shaun.

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Gday,

I got my RB26 back from the engine builders yesterday, and im in the process of assembling the manifolding on both sides. I had a look at the RB26 turbo upgrade sticky thread hoping to find similar setups, but found none. Does anyone have or, know someone with, a Garrett GT35 single turbo on a built RB26 engine? Any idea what power its making?

For reference my engine has:

GT35 Turbo

38mm Tial gate

4inch exhaust

CP Pistons

Prepped rods

Standard cams

9.0:1 compression ratio

Autronic SM4

700cc injectors

Neon lights (that was a joke)

All the usual oil control stuff and a fuel system that will support it.

The car is rear wheel drive only.

I just want to make 300 to 330 rwkw on a safe tune (cant affort another engine failure). Also, i wanted good off boost drivability, hence the 9:1 comp.

Id be interested to hear peoples (informed) opinions on power output for this set up. Please, no negatives, as im still getting over the cost of this process and im feeling fragile.

Thanks,

Shaun.

.

Funny you should ask, a mate of mine's car is on the dyno right now. It is running a forged 26 with 260 degree cams and a .82 gt35r. Just at the early stages of tune but I can tell you with a .6 bar spring the wastegate is open before 3500rpm. Intention with it is to have a really streetable low 11s car with possibility of tens leaning on it. We researched before choosing it and couldn't find anyone running it so hope we are right!

I think u will get there shaun, not sure what boost it will take. With the 9.0 cr hopefully less rather than more :verymad:

Im slowly putting together a 26/30 with prob 8.3 comp and a gt3040, hoping 1bar will see 300rwkw

going into the same car as you :)

Gday,

I got my RB26 back from the engine builders yesterday, and im in the process of assembling the manifolding on both sides. I had a look at the RB26 turbo upgrade sticky thread hoping to find similar setups, but found none. Does anyone have or, know someone with, a Garrett GT35 single turbo on a built RB26 engine? Any idea what power its making?

For reference my engine has:

GT35 Turbo

38mm Tial gate

4inch exhaust

CP Pistons

Prepped rods

Standard cams

9.0:1 compression ratio

Autronic SM4

700cc injectors

Neon lights (that was a joke)

All the usual oil control stuff and a fuel system that will support it.

The car is rear wheel drive only.

I just want to make 300 to 330 rwkw on a safe tune (cant affort another engine failure). Also, i wanted good off boost drivability, hence the 9:1 comp.

Id be interested to hear peoples (informed) opinions on power output for this set up. Please, no negatives, as im still getting over the cost of this process and im feeling fragile.

Thanks,

Shaun.

small gate....... what size exhaust housing you using? 300-330 will be a walk in the park, i just pulled one off a mates car and it made 320rwkw with the .82 (from mem) housing it was too laggy and with a 38mm gate it could not control boost properly over 5000. i reckon your gonna be borderline with boost control issues, i have a 26 setup in ours and i wont go any smaller than a 42mm with the K5.

My car is almost back on the road with...

- RB26DETT (stock)

- 260 JUN cams

- GT35R .83 (custom with Mr Turbo nitride bearings, bigger comp wheel and power ported front cover)

- 6boost manifold

- 4" turbo > 4" cat > PEII

- 60mm gate

- PFC, 700, 044, blah blah

From planning this setup over 3 years ago, and hearing about results from others, i plan to see 300rwkw on 1bar, and low 400's on 2bar. Full boost by 3500-4000rpm (I'm sick of speculating now, I'll just wait and see)

Hope this helps

small gate....... what size exhaust housing you using? 300-330 will be a walk in the park, i just pulled one off a mates car and it made 320rwkw with the .82 (from mem) housing it was too laggy and with a 38mm gate it could not control boost properly over 5000. i reckon your gonna be borderline with boost control issues, i have a 26 setup in ours and i wont go any smaller than a 42mm with the K5.

Lag didn't even begin to describe it....

K5 eh, cats outta the bag :(

My car is almost back on the road with...

- RB26DETT (stock)

- 260 JUN cams

- GT35R .83 (custom with Mr Turbo nitride bearings, bigger comp wheel and power ported front cover)

- 6boost manifold

- 4" turbo > 4" cat > PEII

- 60mm gate

- PFC, 700, 044, blah blah

From planning this setup over 3 years ago, and hearing about results from others, i plan to see 300rwkw on 1bar, and low 400's on 2bar. Full boost by 3500-4000rpm (I'm sick of speculating now, I'll just wait and see)

Hope this helps

Nice combo, power figures seem pretty spot on the stock GT35r with 0.82 made about 320ish at 1.3bar so 300 @1.1bar seem close to the money.

Gate size is dependant on what boost you are running and the setup in question.

I wouldnt call a GT35/82 laggy in a 2.6ltr. I could see it being on show by around 4000rpm.

I say this being i had the big GT30/stock RB25 head with 17psi in by ~4200rpm.

Now i'd say with bit better head setup, tad better cams (stock 26 head im talking), the extra 100hp in comp wheel, would pretty much offset things nicely so it really should be returning ~15-18psi by ~4000rpm. Very hard to talk specifics, so its 'general' for most of it

I was using a 45mm gate, never had a problem as i purchased the right gate (as i intended to run 17psi+)

Its all in the tune too. 4000rpm worth of useable power i had is pretty good going i thought :rolleyes:

Gate size is dependant on what boost you are running and the setup in question.

I wouldnt call a GT35/82 laggy in a 2.6ltr. I could see it being on show by around 4000rpm.

I say this being i had the big GT30/stock RB25 head with 17psi in by ~4200rpm.

Now i'd say with bit better head setup, tad better cams (stock 26 head im talking), the extra 100hp in comp wheel, would pretty much offset things nicely so it really should be returning ~15-18psi by ~4000rpm. Very hard to talk specifics, so its 'general' for most of it

I was using a 45mm gate, never had a problem as i purchased the right gate (as i intended to run 17psi+)

Its all in the tune too. 4000rpm worth of useable power i had is pretty good going i thought :/

Quit rubbing it Ash. It may fall off :rolleyes:

small gate....... what size exhaust housing you using? 300-330 will be a walk in the park, i just pulled one off a mates car and it made 320rwkw with the .82 (from mem) housing it was too laggy and with a 38mm gate it could not control boost properly over 5000. i reckon your gonna be borderline with boost control issues, i have a 26 setup in ours and i wont go any smaller than a 42mm with the K5.

I made a mistake fortunately. The gate is a 44mm tial item not a 38, so it shouldnt be too small.

Im using the 1.06 turbine housing. There's a story behind that though. I had it tuned with the 0.86 housing but it saw boost by 2000rpm and was quite uncontrollable. I assumed that with the high compression ratio, the engine was creating too much gas for the smaller turbine housing to handle, thus boosting really early.

If the gate is too small though, it would produce the same result at higher rpm. Surely the 44 wont be too small.

I'd rather use a lower boost setting and have goo off boost response.

Thanks,

Shaun.

Gate size is dependant on what boost you are running and the setup in question.

I wouldnt call a GT35/82 laggy in a 2.6ltr. I could see it being on show by around 4000rpm.

I say this being i had the big GT30/stock RB25 head with 17psi in by ~4200rpm.

Now i'd say with bit better head setup, tad better cams (stock 26 head im talking), the extra 100hp in comp wheel, would pretty much offset things nicely so it really should be returning ~15-18psi by ~4000rpm. Very hard to talk specifics, so its 'general' for most of it

I was using a 45mm gate, never had a problem as i purchased the right gate (as i intended to run 17psi+)

Its all in the tune too. 4000rpm worth of useable power i had is pretty good going i thought :(

gate size is NOT related to boost it is related to exhaust flow, if it is too small you cannot control the waste gasses correctley and you will either get creep or the boost will climb indefinately, but as he has since corrected his gate size from 38mm to 44mm it is no longer going to be an issue.

as for laggy i usually compare the GT35R against the T67 8cm to my customers and the T67 will be on full song 1.2bar by 3500 and make 300rwkw no dramas i consider this not laggy 17psi on a daily street at 4200 is not exactly responsive. The Gt35R tho will provide more top end probaly around 30-odd rwkw to get this will a T67 requires a 10cm housing and cams (peaks about 340rwkw at 1.3-1.4bar). i do however agree though BANG for buck the GT35R is hard to beat and the extra lag and midrange loss for most is irrellevant cause they saved a bit of coin.... for me its a no brainer as we have both turbos on hand.

Yeh i agree you can get turbos that are a bit more responsive/for less power.

because a GT35 will do more than 330rwkw, but then not good on a stock motor as your really getting up it

Isnt exhaust flow a result of boost (more air)?

You dont have the same exhaust flow @ 16psi as you do at 20psi i thought...

So therefore if you want to run less boost, you must pass more exhaust. More boost, less exhaust.

Thats just they way i look at it and relate, could well be wrong.

Quit rubbing it Ash. It may fall off :(

Least im rubbing my own and not someone else's on a daily basis :P

gate size is NOT related to boost it is related to exhaust flow, if it is too small you cannot control the waste gasses correctley and you will either get creep or the boost will climb indefinately, but as he has since corrected his gate size from 38mm to 44mm it is no longer going to be an issue.

as for laggy i usually compare the GT35R against the T67 8cm to my customers and the T67 will be on full song 1.2bar by 3500 and make 300rwkw no dramas i consider this not laggy 17psi on a daily street at 4200 is not exactly responsive. The Gt35R tho will provide more top end probaly around 30-odd rwkw to get this will a T67 requires a 10cm housing and cams (peaks about 340rwkw at 1.3-1.4bar). i do however agree though BANG for buck the GT35R is hard to beat and the extra lag and midrange loss for most is irrellevant cause they saved a bit of coin.... for me its a no brainer as we have both turbos on hand.

In regards to over boosting:

The way i was looking at it (correct me if im wrong), was that if the engine is producing a given amount of gas and the waste gate is too small to pass it, it will create a back log of exhaust gas, thus creating an uncontrollable over boost situation.

Also, do you think that my GT35 will be more responsive than Ashley was suggesting due to the higher comp ratio?

Shaun.

In regards to over boosting:

The way i was looking at it (correct me if im wrong), was that if the engine is producing a given amount of gas and the waste gate is too small to pass it, it will create a back log of exhaust gas, thus creating an uncontrollable over boost situation.

similar to what i was explaining earlier, we had this issue with a mates 38mm tial gate it was just too small so boost would continue to build and finally reached a equilibrium of 1.5bar.... on a stocky eng it was only a matter of time. so we fixed the whole shebang.

1.5bar is getting to boys level of acceptable boost!

1bar is for girls :D

haha yeah made mid 350rwkw no dramas (other than uncontrollable boost) but the poor old girls catch tank looked like a kettle on full boil at 1.5bar :) tooot tooot

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