1jzgte/2jzgte stock twin turbo power gains

[BlakeNZ]

Mr REE or LITH, can you resize if required, and post images of my engine bay please, in this thread?

[Lith]

[BlakeNZ]

Thanks. Yes, they are stock turbos. The rear one has been reversed to allow both turbos to have 3" intakes, and 3" down pipes, joining to a 3.5" exhaust. The radiator has been replaced with a hilux one, which is narrower, to allow the 3" intercooler piping to have very direct paths. The radiator is set much closer to the fan than standard, allowing the intercooler(600mmx300mmx100mm) to be placed where it is. The retention of the factory fan, rather than electric fans, is a point of difference here. The radiator is taller than standard, and thicker- so i'm hoping the extra 40% volume of fins will compensate somewhat for the smaller frontal area.
The turbo set up was fabricated by Kurt Atzmuller in Australia. Spanner work by Thomas Costello(Palmerston North)
Custom mounting of the radiator and intercooler, sorting oil and water lines, and exhaust fabrication all by Thomas.
Dyno results on tues.

[MAC_HATER]

I need to find some new pants now >_>

holy hell thats awesome

[JZCrazy]

It is looking awesome, Blake.
Kurt has done a good job of the pipe work, and I know some of the problems you've had.
Might have to get a set of hot side pipes (Kurt's standard ones) and a set of HFSW 12A's to (try and) keep up.

Tuesday is the day. I have been waiting for this. 300Kw +.

[BlakeNZ]

No. it is unlikely to go near that, as we know that the 264 cams and cam gears gained your car 31kW, and my cams aren't installed. Also, I'm on standard fuel system, so probably limited to around 250kW at rears. The dyno is simply to establish if the car is worth putting more effort into.
If it looks promising, then the camshafts will go in(high lift Kelford 260s- designed to complement/max out the stock turbos). I will also put in bigger injectors.

[2jayzgte]

No. it is unlikely to go near that, as we know that the 264 cams and cam gears gained your car 31kW, and my cams aren't installed. Also, I'm on standard fuel system, so probably limited to around 250kW at rears. The dyno is simply to establish if the car is worth putting more effort into.
If it looks promising, then the camshafts will go in(high lift Kelford 260s- designed to complement/max out the stock turbos). I will also put in bigger injectors.

Blake are the Kelford Cams as good as the Jun or HKS equivalent's.

I remember back in the day Lindsay Sarchet RIP raved about those JUN 264's and preferred them over the Kelford Cams mind you this was about 3-4 years ago now.

Also just quickly how high are you lifting the stock rev limit to get the full benefit of those cams?

[BlakeNZ]

It's hard to know how good they are, but he assures me that the extra lift over the hks or brian crower cams will yield better results. The HKS and jun profiles have been around a long time now, and appear to have been superceded by GSC and kelford (at least according to supra owners in America). BC and kelford and GSC all tend to much more affordable than hks($1250ish) and jun($1450ish last time i checked)
If i do get to install these Kelford ones, it will give us a fairly good indication as to what suits a maximum effort stock turbo JZ application, as we have already done the BC264 cams (before and after) dynos on a stock turbo 1jz.
According to our results, the BC 264s gave a fantastic gain, much more than my HKS 256 cams in my previous 1jz. On that car, we lifted the rev limit to 7500rpm. (The rev cut may be at 7600rpm, I can't quite recall)
A rough guide is that the cams are giving an extra 1000rpm of usable power.( factory power falls away quite quickly after 6300rpm from memory)

[2jayzgte]

It's hard to know how good they are, but he assures me that the extra lift over the hks or brian crower cams will yield better results. The HKS and jun profiles have been around a long time now, and appear to have been superceded by GSC and kelford (at least according to supra owners in America). BC and kelford and GSC all tend to much more affordable than hks($1250ish) and jun($1450ish last time i checked)
If i do get to install these Kelford ones, it will give us a fairly good indication as to what suits a maximum effort stock turbo JZ application, as we have already done the BC264 cams (before and after) dynos on a stock turbo 1jz.
According to our results, the BC 264s gave a fantastic gain, much more than my HKS 256 cams in my previous 1jz. On that car, we lifted the rev limit to 7500rpm. (The rev cut may be at 7600rpm, I can't quite recall)
A rough guide is that the cams are giving an extra 1000rpm of usable power.( factory power falls away quite quickly after 6300rpm from memory)

Can definitely verify that last statement to me my power and torque curve in my car is flat at about 6-6100 rpm not much happens after that.My rev limit is set at 7000 RPM

The reason I ask is I'm interested to see what happens heat wise with the increased rev limit.I know at the moment my cars rev limit and boost levels the water temps are a rock solid 85-90 deg C at that given rev limit.

I see a friend of mines track specced single turbo car track car's rev limit is set at 8000 rpm and he see's 110 degree C water temps after a 5 lap run.

[BlakeNZ]

does he have electric fans and you have viscous and shroud?

[2jayzgte]

does he have electric fans and you have viscous and shroud?

Yeah I think he still runs the factory fan and shroud not sure what radiator though.

[BlakeNZ]

the best power adder for a stock turbo soarer is definitely THIS!!!!
http://www.trademe.co.nz/motors/car-par ... 871769.htm

EDIT : OK so this link no longer goes to the image i wanted. It was an entire soarer body made out of fibreglass!

[BlakeNZ]

just an update. The soarer was put on the dyno last night, ready for today. We ran it up on stock ECU(stock turbos/stock fuel system) and we hit boost cut (approx 13.5 psi) at 5400rpm on one run (203 rear kW) and 6200rpm (216 kW).
It was very rich(almost off the scale) so we thought there was plenty to be had for the next morning. Things were looking promising.The Power FC was installed, ready for this morning.
Today,jhe car peak boosted at 17.8 psi. This is without a boost controller, and with ported waste gates. Strangely, despite being able to give it a full rev run, and 4 psi more boost,and having ability to fully tune ignition and fuel, it didn't make any more power. Given the unlikeliness of this occurrence, I'm sure I have a problem either with the ECU or the tuner.
Sadly, the car stopped producing boost, which became understandable when they found one of the ceramic exhaust wheels at the back of the dyno bay! tuner believes both have let go, but I won't know until they get taken off.
I'll have my spare ones put on. (though 20 year old turbos with unknown history can be a lottery, as is evidenced here.)Is there any other damage? i don't know.
I was (largely)expecting to sacrifice at least one pair of turbines whilst pushing the envelope, but i was expecting that to be at 25psi, not 17psi.
As a note, in no way do i attribute the failed exhaust wheel to the tuner- he tends to be cautious. I suspect they were compromised by my heavy handed assembly technique, but we will never know. (a turbo shop will assemble the next pair)

[Lith]

Today,jhe car peak boosted at 17.8 psi. This is without a boost controller, and with ported waste gates. Strangely, despite being able to give it a full rev run, and 4 psi more boost,and having ability to fully tune ignition and fuel, it didn't make any more power. Given the unlikeliness of this occurrence, I'm sure I have a problem either with the ECU or the tuner.
Sadly, the car stopped producing boost, which became understandable when they found one of the ceramic exhaust wheels at the back of the dyno bay!

Again sucks to hear the dyno session went far below ideal - stuff like this is why I ended up getting into tuning myself, the amount of times you hear of dyno sessions where a car hasn't performed as hoped (ignoring the exhaust wheel failure, I'd be putting that as likely being collateral damage on a mission like this) I really like to know as much about what is happening to ascertain if things were going in the right direction. Information that would have been available at the time of tuning to determine how to move forward from here, or roughly what to expect next time:

- What was boost at peak power when it ended up making the same power with the PowerFC as it did with the stock ECU? Was boost dropping back to 13-14psi?

- HOW rich had it got, and what AFR was it tuned to with the new ECU?

- Did the difference in injector pulse width at key points between the lower and higher boost runs seem proportional to the extra boost versus AFR? ie, if for sake of argument it ran 10:1 on the stock ECU at 13psi and then was tuned to 12:1 at 18psi on the PowerFC then the injector pulse width at peak power probably shouldn't be much different if there is no major restriction at that point

- Was this using any form of boost control, and if so - what... and was it working hard to hit/hold 17-18psi? And if not, how come it ran 13.5 on the stock ECU and 18 on the PowerFC?

- Was it very knock limited?

And really those are just the bare minimum obvious things I'd like to consider with this. I find it frustrating that the money and time to put the car on the dyno may have been invested and what seems like no real information being acquired from doing so - given it should be the perfect opportunity to build a really good snapshot of what the engine setup wants and might offer.

Good luck with the next step

[BlakeNZ]

Quote"Today,the car peak boosted at 17.8 psi. This is without a boost controller,"
so the car is just on wastegates. The car did 13.5 on stock ECU because it hit boost cut. I have no doubt it would have hit 17-18 psi on the stock ECU if i had a boost cut defender installed. The set up obviously has great flow. Factory boost is 10psi.
unfortunately, we have no idea what the pulse width of the injectors are doing on the stock ECU. It doesn't give the same feed back a Power FC does.
i will get it fixed, and will try again. Likely on a different dyno, I will use the stock ecu as a base run, then the power fc for a power tune, then if that returns a poor result ,i'll put in the hks F-con V pro Gold.

[Lith]

The car did 13.5 on stock ECU because it hit boost cut.

Oh yeah.... makes sense

unfortunately, we have no idea what the pulse width of the injectors are doing on the stock ECU. It doesn't give the same feed back a Power FC does.

Posting in morning before I've woken up properly bad - though still, more what I was getting at was an over specific way of saying is it should be pretty clear if the flow was going up in proportion to pressure during tuning. Did the boost ever stabilise or was it still climbing at 17/18?

[BlakeNZ]

as far as i'm aware it was stabilising around that point. Will ask him to clarify.

[e30-323ti]

It will still be 'boost creep' that has got it to ~17psi over the stock acutator pressure (~12psi).
Even with your ported WG's it still won't be enough with the tiny CT12a turbine wheels, and chances are, they can not physically pump more that 17-18psi (thus the apparent 'stabilising) as they are well out of their efficiency range.

Interesting experiment though!
Were you hoping to see some gains with the re-oriented turbo's Vs the traditional 'twin dumps' ??

ps.I've got a pair of good twins under my bench if you need more cannon fodder.

[Lith]

and chances are, they can not physically pump more that 17-18psi (thus the apparent 'stabilising) as they are well out of their efficiency range.

That's what I was thinking, or wondering - the poor old things starting to get near choking, though giving the ports are still open it's probably not quite the same as doing a banzai run I'm just curious about how the thing didn't end up with more peak power than before, presumably it was running a similar boost curve each time - so perhaps peak power was reached at 13psi and ~6000rpm and then levelled off as engine VE dropped... any extra boost just evening up the difference? Hard to say, but it's hard to swallow that there would be no torque improvement with 4-5psi more boost.

ps.I've got a pair of good twins under my bench if you need more cannon fodder.

Holset going for you?

[BlakeNZ]

the reversing of the rear turbos only advantage is that it allows a bell mouth to be attached to the comp cover, and a 3 inch intake pipe to it. When rear facing, the comp cover is too close to the firewall to allow this. It is also quite difficult to get two 3" dumps on a normal 1jz ct12A configuration.