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Old 26-03-2017, 02:20 AM
theboostshack theboostshack is offline
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Default WMI tuning and results Part 2

G’day guy,

I’ve been posting on this forum for a few years now but this is my first post since changing user name. Just wanted to shed some more light on the results from most recent experimentation with the water meth injection system fitted to the boost shack 1600. The previous results can been seen here http://www.aquamist.co.uk/forum2/vbu...ead.php?t=2987
In this instalment, the aim was to optimise the tune in the lower RPM range and increase the total power output by increasing the water meth flow to around 50% of total fuel flow. This equated to roughly 1250cc/min. The system was set up to use a total of 4 jets, 3 in the charge pipe post intercooler and 1 pre turbo.
Tuning saw us achieve some great gains in the lower and mid range RPM, as you can see from the before and after dyno pictures below. But with the water meth activated, we soon realized that this configuration was not yielding the results we were after, with a 16kw decrease over our last peak numbers.
At this point, we took a set back and sat down with the Unigroup Engineering crew to investigate the possible causes of the drop in power and a way ahead. In the end it came down to the fact the we were injecting too much water meth in a localised area, as we had over 1100cc/min being injected at one area post intercooler. This caused the air to reached and exceeded 100% saturation point, meaning the amount of air entering the engine could no longer suspend the liquid being injected in an atomised form. This causes overcooling of the combustion process due to poor atomisation, leading to a loss in power, which is exactly what we were experiencing.
It was decided that we would remove one of the three charge pipe jets which would reduce the post intercooler injection to around 800cc/min. This resulted in an 11kw in in power and a much nicer power curve right through the rev range. That said, we were still 5kw off our previous peak of 336kw. We decided to leave it there for now, as we will be making some changes in the near future, which we will expand on shortly.



During the tuning process, we paid close attention to the EGTs, via the thermocouples fitted to the exhaust manifold. A significant temperature drop in EGTs was noticed when water meth was activated, as was the fact that cylinder number 2 was running quite a bit hotter than the rest. Some individual cylinder fuel adjustment was used to quickly solve this issue.




During a recent outing to Sydney’s roll racing, we did some data logging. The ambient temp on the day was up around the 38-degree mark. In the waiting lanes, air intake temp reached 50+ degrees. At the end of each run, air intake temps were down to 40 degrees.
In the next instalment, we will be maintaining the current flow rate but making the switch back to direct port water meth injection. This will be done using 1x140cc/min jet in each inlet runner, 1x250cc/min jet post intercooler piping and 1x150cc/min jet pre turbo. The reason for making the switch is for better atomisation, less chance of saturation and a more equal distribution of the water meth. We are hopeful that with this change and some more fine tuning, we will be able to achieve 350rwkw. Only time will tell so stay tuned. Please feel free to add to the discussion by leaving any questions or feedback you may have. The links below are some videos of the car at Sydneys Roll Racing events. Cheers, Orlando

https://youtu.be/mDHA5L54B6A

https://youtu.be/aXkfvyRhUyQ
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  #2  
Old 26-03-2017, 08:03 AM
rotrex rotrex is offline
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Default Re: WMI tuning and results Part 2

DP should help here.
Your inlet manifold is not desiged for wet flow. Injecting a lot of fluid upstream of the plenum will have a lot of fluid running along the walls.
And this flow is not uniformly distributed among the cylinders. WW2 aero engines were designed for wet flow.
A good indicator are your cylinder trims. The more they increase with increasing spray, the less uniform the spray is distributed.
You might also get EGT related artifacts from big droplets passing straight through the engine and evaporating in the exhaust manifold. You might get more cooling from more fluid coming out of the exhaust port.

Unequal water contents across the cylinders will lead to unequal flame front speeds.
Cylinders with more water will hit max torque before the ones with less water.
This will flatten the power vs ignition timing curve leading to lower max power.

The methanol acts as a high octane fuel that is partly vaporized before entering the cylinder. It masks some of the distribution issues. This is the reason I believe many have better success with higher methanol content. They benefit form the high octane number, not that much from evaporative knock surpession in the cylinder.
If you run pure water, any issues in spray distribution show as knock on the cylinders that get less flow or the bigger droplets.

Any methanol that evaporates from heat extracted from the manifold or pipes leading to the engine will reduce air density. Any meth that does not evaporate from heat extracted from the air will cause no air temp reduction and hence no density increase. This effect is, as mentioned before, contributes only a part of the effect.
It works well for low flow rates injected in the front section of the inlet tract.
To get it to work well for higher flow rates, you need a very fine mist from air assited nozzles. Riceracing's setup is nice example.

With 350kw, you will need way bigger jets than 4 140cc jets for DP.


Air saturation is largely irrelevant at high methanol flow rates.
You do not gain much power by charge cooling outside of the cylinders.
You want small droplets within the cylinder for knock supression.

If you still get knock with DP before hitting best torque, increase flow rate.

Mount the jets on top of the manifold in line with the injectors.
If mounted elsewhere, the spray will not be distributed well within the cylinder itself, especially front to rear.
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Old 01-04-2017, 01:25 PM
UCTURBO UCTURBO is offline
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Default Re: WMI tuning and results Part 2

Ive done abit of a backyard DP injection setup on my 2jz. Ive got 6x240cc DP injectors and 1x300cc pre turbo injectors. On 23psi my fuel flow is around 60% or 3600cc ( ID1000's ) so my injection rate is about 49% without missfire ( 50/50 by volume ).

To be noted also my injectors only see approx 40psi so atomization isnt great but the valve is also closed for some time during the cycle so the water/meth and fuel will pool a little anyways. Ive also ran less pressure ( 20psi ) for less flow without issues.

Heres a little video of it on 16psi and approx 1300cc ( 20psi injection pressure ) 60/40 water/meth. Going by the weight and mph its making around 530hp at the flywheel. Have since dropped the compression and 9.2:1 and put stock cams back in it, will see how it goes.....

https://www.youtube.com/watch?v=8gjifYRPYsc

Cheers for a good read and actual results
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Old 02-04-2017, 05:38 PM
Richard L Richard L is offline
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Default Re: WMI tuning and results Part 2

Quote:
Originally Posted by theboostshack View Post
G’day guy,

I’ve been posting on this forum for a few years now but this is my first post since changing user name. Just wanted to shed some more light on the results from most recent experimentation with the water meth injection system fitted to the boost shack 1600. The previous results can been seen here http://www.aquamist.co.uk/forum2/vbu...ead.php?t=2987
In this instalment, the aim was to optimise the tune in the lower RPM range and increase the total power output by increasing the water meth flow to around 50% of total fuel flow. This equated to roughly 1250cc/min. The system was set up to use a total of 4 jets, 3 in the charge pipe post intercooler and 1 pre turbo.
Tuning saw us achieve some great gains in the lower and mid range RPM, as you can see from the before and after dyno pictures below. But with the water meth activated, we soon realized that this configuration was not yielding the results we were after, with a 16kw decrease over our last peak numbers.
At this point, we took a set back and sat down with the Unigroup Engineering crew to investigate the possible causes of the drop in power and a way ahead. In the end it came down to the fact the we were injecting too much water meth in a localised area, as we had over 1100cc/min being injected at one area post intercooler. This caused the air to reached and exceeded 100% saturation point, meaning the amount of air entering the engine could no longer suspend the liquid being injected in an atomised form. This causes overcooling of the combustion process due to poor atomisation, leading to a loss in power, which is exactly what we were experiencing.
It was decided that we would remove one of the three charge pipe jets which would reduce the post intercooler injection to around 800cc/min. This resulted in an 11kw in in power and a much nicer power curve right through the rev range. That said, we were still 5kw off our previous peak of 336kw. We decided to leave it there for now, as we will be making some changes in the near future, which we will expand on shortly.
Apologises for the late post.

Have your consider reducing the spark gap just in case the ignition system is stressed and not allowing sparks to fly? 0.4mm is not out of the normal on some very powerful engine I came across in the past.
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  #5  
Old 15-04-2017, 01:49 PM
RICE RACING RICE RACING is offline
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Default Re: WMI tuning and results Part 2

Put on a M&W CDI 250mJ (hi switchable) with correct coils and their false 'diagnosis' of issue will go away
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Old 19-04-2017, 11:30 AM
theboostshack theboostshack is offline
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Default Re: WMI tuning and results Part 2

G'day guys, sorry for the late response and thanks you all for your feedback.

Rotrex, you mentioned that I would need greater than 140cc per cylinder to reach a target of 350kw. What amount would you recommend per cylinder to reach this target?

Richard, my current ignition system seems up to the task. I recently made the switch from a CDI to an inductive ignition system. I know this may seem a little odd but the car actually performed better across a wider operating range now than it did with the CDI system.
Cheers
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Old 19-04-2017, 01:13 PM
RICE RACING RICE RACING is offline
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Default Re: WMI tuning and results Part 2

What CDI system did you replace (specification of it and matching coil) and what condition was it in?

I've tried every inductive ign snake oil out there and nothing comes close to matching a M&W proDrag2 Hi/Lo combo, you will need x 2 of those boxes and their latest CDI coils and it wont have the issue your 'tuner' says it has It's an ignition misfire cause its incapable of running a true water injected car, tune the engine don't let it tune you
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Old 19-04-2017, 01:56 PM
theboostshack theboostshack is offline
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Default Re: WMI tuning and results Part 2

It was an autronic 500r CDI unit with bosch coils. I can't remember the exact coil specs.
I now use LS2 coils with Denso Iridium IK22 spark plugs gapped to 1mm. No missing even when running over a 1000cc of water meth and 35 psi boost. I can also run as lean as 15:1 afr when cruising which was never achievable with the CDI system. Inductive ignition systems have come a long way in recent years and not a moment too soon.
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Old 19-04-2017, 03:24 PM
RICE RACING RICE RACING is offline
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Default Re: WMI tuning and results Part 2

They don't work at 60psi boost and 0.550L and 10,000rpm on methanol ;-)
Anything that is high powered, 50%+ excess fuel ratio, water injected, high rpm is all CDI based, I've never seen one car run inductive based coils that worked.

You may not hear the misfire but it will show up as a loss of power
most common mistake I see is people using those snake oil coils then blaming everything under the sun for loss of power.

p.s. 500R (they made a couple of versions) but most are lower energy (105mJ), and if not run with good coil will not be a reflection of a 'CDI' v's antique ign system BTW, the plug gap is way too large, if its still low in power and you can or willing to try for a 4cyl turbo water injected car 2 x M&W ProDrag2 boxes in 250mJ/125mJ (HiLo) will fire anything and be suitable for constant duty road/race use.
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Old 19-04-2017, 07:40 PM
rotrex rotrex is offline
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Default Re: WMI tuning and results Part 2

Quote:
Originally Posted by theboostshack View Post
G'day guys, sorry for the late response and thanks you all for your feedback.

Rotrex, you mentioned that I would need greater than 140cc per cylinder to reach a target of 350kw. What amount would you recommend per cylinder to reach this target?


Cheers
I'd say 200-250cc per cylinder comes closer to being useful and a little headroom won't hurt.

I'd skip all the post intercooler jets and just consider keeping the pre turbo jet.
As the 250cc per cylinder need to be injected into some 2+ bar of boost, you will need either 10+ bar of pump pressure with 0.5mm Aquamist jets or up the size to 0.6mm if you stick to the 7 bar of pump pressure.

Here are recent 390 whp from a 2l 4-cylinder running 4x 0.5mm Aquamist jets at 1.55-1.85 bar without any knock.
http://www.aquamist.co.uk/forum2/vbu...?t=2863&page=4

1mm plug gap and misfires under very high boost are not unheard of :-)
Riceracing has posted a fair share of results for high boost high HP WI.
Once you have uniform spray entering all combustion chamber is a reasonably uniform manner, it is typically only the ignition system holding you back.
For dry flow multi cylinder manifolds there are only two ways of achieving a uniform distribution from all I have seen and read: pre turbo with a air assisted nozzles and their extremely fine mist or direct port.
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