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Is water/meth injection safe? undecided


msupra1
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On my 6-speed car I'm running a S366 turbo, 3" dp/4" exhaust, 800cc drop-in Injectors, AEM V2 standalone.

The car made 460whp/430wtq, dyno reads in wheel HP so that's about 530bhp.

 

It's running 1.25bar which was the most as its getting some detonation because that's the limit of Pump gas.

 

It has the stock j-spec cams and planning to do the GSC S1 or HKS 264 next, after the cams I think that should put me above 580bhp at the same boost level.

 

Lets say I run just a bit more boost, 1.4 - 1.5 bar, that should put me at a power level I'll be more than happy with.

 

The only way to achieve this boost is with meth injection. So I won't be running some crazy boost, just a bit more than what pump gas allows. I have been doing a lot of reading on meth Injection and I'm really undecided. The main thing for me is to have a safe setup as the last thing I want is any major engine problems. It seems like a lot of people run it and it's good but I heard some people blew their motors from meth kits failing.

 

Is there any recommended/best quality kits, and is running straight meth ideal or 50/50 mix? I don't live in hot climate.

 

Cheers

Edited by msupra1 (see edit history)
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I would install a ethanol/methanol capable fuel system, and then add ethanol or methanol to the fuel in the tank.

 

I think the AEM v2 has flex fuel capability ... this would allow you to run anything between pump gas and the maximum ethanol/methanol % the car was mapped on.

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Whatever kit you get, make sure it has good built in safe guards (to reduce boost and/or timing) so that if anything fails or you run out of meth, you don't blow your motor.

 

Agreed, if you intend to map for the WI to allow for more timing and boost this is a requirement which is why I have only ever used WI un-mapped, some kits have flow sensors etc which you can use to pull boost and timing back.

 

The better solution in my mind has already been mentioned, a flexfuel sensor and strategy, just chuck some meth in the tank and let the ECU do the rest, as long as its configured properly and your fuel system can handle it ;)

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This is the conversion between Pump gas octane to RON

91 octane = 95 RON

93 octane = 98 RON

I run 100% 94 octane... but the quality of the gas here isn't that great so I'd estimate it to be equivalent to 95 RON.

 

Regardless, I am starting to get some knock/detonation at about 19psi (1.3 bar) and tuner recommended not pushing it further.

Most people don't run higher than this boost on pump gas here. So I don't have much more boost to play with on pump fuel.

The tuner himself recommended that I go with a meth kit, that's what most people do here.

 

My fuel system has SARD 800cc drop-ins & Walbro 400lph pump, the lines are stock.

I bought these injectors used and the previous owner was making 565whp on them.

Edited by msupra1 (see edit history)
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Whatever kit you get, make sure it has good built in safe guards (to reduce boost and/or timing) so that if anything fails or you run out of meth, you don't blow your motor.

 

Yes that's one of the reasons I'm trying to figure out if meth is something for me. I definitely want to run it as safe as possible. As mentioned, I won't be doing massive boost just something moderate.

I'll have to see what kind of safeguards my supra builder recommends

 

As for kits, I was looking around and it seems like the AEM is most popular and price seems good.

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Could be down to your pump fuel, Although you might need another fuel pump, I run a single 485 and that stopped me at 580bhp fly.

 

Our 99ron is good for over a 1000bhp with the right fuel setup.

 

If you can get your hands on methanol/ethanol easily your best bet would be to add a fuel flex sensor and map on that, put the methanol straight in your fuel tank. I think you will still need another fuel pump though.

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Hmm, is there anyway to check if the fuel pump is running out? I figured the walbro 400lph alone was good for like 550whp easy

 

Wouldn't it end up being quite pricey putting meth directly into the tank as apposed to having a meth kit? I don't really know much about this stuff.

someone recently opened an E85 station here but its not ideal to run as its quite some distance from home. I'd really like to stay on pump for simplicity and seems like the meth injection Is common thing to do here.

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Your mapper should be able to tell you.

 

Myself. I've never liked the water/meth kits, a single jet spraying in near the TB is never going to give even distribution over all cylinders. Good thing with running a fuel flex sensor (if your ecu can control one) is that once it's been mapped it looks after itself adjusting boost/timing depending on what fuel is in it, you want a bit extra power one day you simply fill up with e85, that's how I run mine and its s brilliant setup imo.

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The Walbro 416 (aka 400, aka 485) is good for over 600whp when using E85 (800+ whp on pump gas), so none of you guys were running out of pump flow. Perhaps the lines, filters or injectors were the flow limiting issue?

 

e.g. http://www.supraforums.com/forum/showthread.php?686598-Single-Walbro-Dyno-679whp-E-85

 

image

Edited by V8KILR (see edit history)
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As already said, I would get it mapped safely for the required power you need using the fuel available, and just use WI as an extra safety net rather that rely on meth to boost the performance, although with a suitable ECU that has all the safety fail safes its not too much of a worry, but it only takes not being able to get your usual fuel to cause a problem.

 

And to answer the main question...there is nothing unsafe about WI. its just the way its set up and used that can cause problems...just like anything else.

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the tuner told me and I remember it quite clearly that the engine "was starting to get some knock at 19psi" , 1.3bar.

the car had quite a bit of dyno time with a full tune, detonation was just a word I used but I thought it was same thing more or less.

 

There is no issue with the car its simply not high enough octane fuel to support the boost if I decide to go over 1.3 bar, it becomes unsafe.

 

 

May I ask what boost level you guys are able to run there on straight pump gas?

Edited by msupra1 (see edit history)
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The Walbro 416 (aka 400, aka 485) is good for over 600whp when using E85 (800+ whp on pump gas), so none of you guys were running out of pump flow. Perhaps the lines, filters or injectors were the flow limiting issue?

 

e.g. http://www.supraforums.com/forum/showthread.php?686598-Single-Walbro-Dyno-679whp-E-85

 

http://i52.photobucket.com/albums/g24/prelude760/Sound%20Performance/Fuel%20Pump%20comparison/FuelPumpcomparison_graph.jpg

 

 

 

What is the Voltage Output axis supposed to indicate?

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the tuner told me and I remember it quite clearly that the engine "was starting to get some knock at 19psi" , 1.3bar.

the car had quite a bit of dyno time with a full tune, detonation was just a word I used but I thought it was same thing more or less.

There is no issue with the car its simply not high enough octane fuel to support the boost if I decide to go over 1.3 bar, it becomes unsafe.

 

Lower octane is not the only cause of det, you have already said others are able to run more boost on same fuel.

 

What ignition setup do you have and what plugs are you running.

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Guest FullAttack
Race fuel is relatively cheap in the USA, you might consider dual maps and just fill up with, or run a mix of, race fuel when your present power level is insufficient. With some "proper stuff" in it, the amount of extra advance you can run is amazing.

 

What he said..

 

But, to run race gas you'll need to upgrade your fuel lines and injectors etc.. Race gas/meth/ethanol eats away at normal fuel grade rubber.. You need proper E graded stuff..

 

And with ethanol mixed gas you'll possibly need bigger injectors as you'll need to pump more fuel per cycle to get the equivalent bang..

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