Rb25 + Gt3076R & Mods, Made Low Power On Dyno Tune Why?

[DriftSquad]

Lol what a thred hijack .. ^^"

Yeah dude I'm working on it. Didn't know I had issues haha. Well I'm surprised with all the leaks in the system it idled so well! By the end of the day I'll have some other results

[scotty nm35]

Because it was tuned like that. As above, the tuner probably wouldn't know about the leaks, they just tune with what they have and make suggestions later.

I just reviewed my last boost graph from Trent, 20 psi by 3700, 30 psi by 3900 on a .82 GTX3076, just to give you some idea. There isn't much difference between the .82 and .63 spool I believe, perhaps 200-300 revs, but the top end would feel so much better with the larger housing, and feel more responsive once on boost. As said, sort you issues first though.

[GTScotT]

Looking forward to seeing improved results.

[Guilt-Toy]

it must be hard in the UK. I nearly went there

[DriftSquad]

Okay so bit of work got done today.

All leaks are now fixed. The throttle body leaking nipple. And the plenums boost signal nipple fixed. Also the one intercooler pipes with 2 pin holes are fixed.

Just replaced all injector seals and had them flow tested just for the shit of it.. re pressure tested. Found no more leaks in the system.

I also ran a compression test with all plugs out and wide open throttle.

1 = 162

2 = 155

3 = 150

4 = 157

5 = 160

6 = 160

A lot better then what I though it was going to be the motors had a hard life.

Motors is all back together and runs well. I'm still in the market for an .82 housing wich isn't easy to find ATM.

[Guilt-Toy]

engine is in tip top condition. forget about the .82... just fix all the issues.. you will be surprised with how a leak free setup will run

I like a nice small rear, it comes on quicker lol

[skylinecouple]

Everyone's wise afterwards, the reason its fixed is because of DriftSquad doing a great job with diagnosing the

leaks.. from what I read there wasn't many explanations except the housing was too small?? so if a tuner says

a 0.63 GT3076 cant do more than 225kw, then yes ill try someone else thanks...

Ive been thru probably 3-4 so called great tuners in Brisbane, some are highly regarded etc.. and one thing that

remains clear is that if your not spending big $$$$ they simply don't give a sh#t..

Totally agree. I have zero faith in so called big work shops as I have said before. Start off with an Apexi PFC and learn to tune yourself. It doesn't cost much to hire a dyno or get somebody like Toshi to help you out and teach you. My 1st engine bent all the valves due to the tuner telling me five times how there was nothing wrong with it (years ago). The timing belt had lost all it's teeth, every valve was bent. Engine number two was the mechanic of a big work shop using the plastic heater hose as a lever to hold the turbo water feed in place at the back of the engine. Two days later I ran out of water and lifted the head in the middle of nowhere. Engine number three going in next week. My dirty thirty isn't finished yet so 2nd hand engine going in with cams.

Learn to do everything yourself. YOU are the only one you can trust.

[Badgaz]

Totally agree. I have zero faith in so called big work shops as I have said before. Start off with an Apexi PFC and learn to tune yourself. It doesn't cost much to hire a dyno or get somebody like Toshi to help you out and teach you. My 1st engine bent all the valves due to the tuner telling me five times how there was nothing wrong with it (years ago). The timing belt had lost all it's teeth, every valve was bent. Engine number two was the mechanic of a big work shop using the plastic heater hose as a lever to hold the turbo water feed in place at the back of the engine. Two days later I ran out of water and lifted the head in the middle of nowhere. Engine number three going in next week. My dirty thirty isn't finished yet so 2nd hand engine going in with cams.

Learn to do everything yourself. YOU are the only one you can trust.

Yeah ^^ what he said. I'm lucky enough to have a good friend of mine who tunes cars for a hobby. he has taught me the basics with my powerfc....you can do everything a tuner does on the road, sticking to the speed limit of course all you need is your mate in the passenger seat, wideband o2 sensor up the pipe, a link knock detector and laptop with relevant software...logs some driving (drive the way you normally would) check logs and adjust maps as necessary.

[Badgaz]

i'm not sure why there is all this talk of the turbine a/r...i'm still running the stock 0.46 and making around 240-260kw.

[wolverine]

Stock turbo 240-260rwkw?

[Ben C34]

i'm not sure why there is all this talk of the turbine a/r...i'm still running the stock 0.46 and making around 240-260kw.

Why are you confused?

Driftsquad wants more power than that.

Edited February 13, 2014 by superben

[Badgaz]

nah not stock...just stock housings, replaced the turbine with stage 1 t3 with a 10 degree back cut. the core is now garret type and the front housing machined out as far as it will go to fit as large as i could fit wheel in it...56mm inducer from memory....it was a long time ago.

[Badgaz]

Why are you confused?

Driftsquad wants more power than that.

not confused, i guess i just agree with guilt toy...changing an exhaust housing at a guess can be an expensive exercise.

[Badgaz]

Stock turbo 240-260rwkw?

its probably a slightly larger than stock A/R because of the machining...but it is the 'stock' one.

[Guilt-Toy]

Lol what a thred hijack .. ^^"

Yeah dude I'm working on it. Didn't know I had issues haha. Well I'm surprised with all the leaks in the system it idled so well! By the end of the day I'll have some other results

it idled well because its running a map sensor system.

[scotty nm35]

not confused, i guess i just agree with guilt toy...changing an exhaust housing at a guess can be an expensive exercise.

What do you mean at a guess? Plenty of people running .82 housings on GT30's and loving it. Do you think the smaller housing will feel the same on boost? There are tradeoffs, namely torque and top end response. That's why you need to match the turbine AR to the engine size, and where you need the power in the rev range. Every build is different.

I used to think smaller housings were great, and they are in some cases, but after running the 1.06 I realised there is much more to large turbo's than trying to spin them up quickly with a small nozzle. Let the engine breathe, don't strangle it, or you may as well just shove a smaller turbo in there for better response.

Now is the time to swap if you are going to, seeing you need a re-tune anyway.

[DriftSquad]

Yeah I'm definatly keen to try a bigger housing can't seem to find an aftermarket one with 4. Bolt rear housing only vband. No one is selling a used garret one

[Badgaz]

i mean 'taking a guess' that your problems are due to a smaller a/r turbine, without using some evidence and fact.

[AngryRB]

as a reference, Simon-14 used a 0.63 on his drift car early on and reused it on the 3L and said it was pretty savage with heaps

of midrange torque, obviously it was choking it up top though but all depends on your usage. On the street, 0.63rear with E85

for me, cause 4000rpm is too late . For the price of the rear housing you could set it up and run E85 and love it.

Edited February 14, 2014 by AngryRB

[scotty nm35]

all depends on your usage.

For the price of the rear housing you could set it up and run E85 and love it.

^This.

If you can find someone to swap it with, I would do it. Otherwise e85 will 'fix' it.