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NSW supra club Member
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Discussion Starter · #1 ·
Hey guys, sorry of this is in the wrong section, if so i appologise.

I have a dyno tune coming up on wednesday, and am looking for some helpfull suggestions/hints.

I will be using 98octane pump, wich is probably similar to you guys 93oct. and tuning it for ~18-20psi without meth/water injection.

Then i will be giving the meth/water injection tune a go, its a dereks kit.
What i was hoping, was to be able to boost to around 28psi with the mw kit?, i have all the supporting injectors/pump/ecu mods, and a gt42 garrett(74mm).
What i would really like to know is, should i stick to the 50/50 mix ratio? i mean, if i have enough fuel supply, is there any benefit of going more meth. then water, or wise versa?
Is the 50/50 mix the optimum ratio for high boost?
would 50/50 mix be teh best ratio to surpass detonation?

any helpfull comments regarding this would be appreciated.

cheers and thanks to all that reply :) looking forward to some numbers.
 

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Kwan Jul Sul Freak
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Read the Sticky post by meth/water users. There are 3 or 4 peeps who have posted their setups and have run 28psi on pump.

http://www.supraforums.com/forum/showthread.php?t=267257

If you have 98 octane at the pump, you should get 28psi on M/W with the M15 nozzle. I would say thats as high as I would go on your 98. Set your meth pressure switch for around 12-14 psi and watch your EGT's. 50/50 is the best all around combo for knock supression and fuel enrichment. If you are going with a larger nozzle, use less water. Too much water content and the car will sound like it is bogging under high boost.

I have seen Buick GN guys who run up to 30 psi on pump gas with meth/water spraying. Here is a guy making a 10.17 second pass on pump gas. Crazy sh##.

http://home.att.net/~alkycontrol/images/Gene_10.17.wmv
 

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No way I'd try boosting that high without at least monitoring timing and preferably knock. I had big expectations but still get knock past 22 psi.
 

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i don't know what kits you all are running, but with a good meth kit and 100% methanol you should be able to run as much boost as your turbo can push.

i hate reading all these thread where people are diluting there alky with water. why would anyone wanna do that.
 

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wastegate hose is pulled
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50/50 is the most effective ratio for detonantion supression and power adding. If you are out of capacity on your gasoline fuel system, adding a higher methanol percentage will provide a "band aid" fuel system upgrade.

The ammount of boost you should try running is dictated by the maximum flow of your fuel systems and the m/w to gasoline ratio you are using, the a:f ratio, what ignition timing you are using and how much peak cylinder pressure you are making. Sounds like a bit of juggling, eh? That is why race gas and a single fuel system is better IMO, it is safer based on the tried and true K.I.S.S. principle. Anyway, there is plenty of officially documented research on this stuff floating around the www, from back when the military was interested in it if you care to look it up. I thought some of it was fairly informative.

If you are bringing the car to a tuner, hopefully they have a fair understanding of this and can guide you to a safe and also powerful state of tune.
 

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NSW supra club Member
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475 Posts
Discussion Starter · #7 · (Edited)
Hey guys,
just had a dyno tune and honestly, all i can say is im very dissapointed in the power readings.

Its a jza80 supra, converted to a single turbo, garrett gt42(74mm), has all the fuel(850cc inj) /pump/fmic ect and running e11 haltech.
Engine is totaly stock, and also note, the CAMS are stock JDM spec, wich are smaller then the US spec.
Now, being that i run a haltech, i thought i would use Matt/hitman to tune it, who is very popular down here with haltech's.

Well, the results are:
at 19psi = 306KW/410hp.
at 25psi = 324KW/434hp (spraying meth/water on that run.

as you might be able to see, there looks to be something wrong! as far as i know, people with such a turbo are making a lot more power then me, and some are making more power with less boost as well as smaller turbo's(like gt35/40 or to4z).Matt showed me some graph's of similar supras with teh smaller turbos making over 500hp+ on less boost.
AFR was around the 12.0:1 and there was no obvious problems that we could see/tell!
i was expecting to see close to 400kw(536hp) without spraying meth/water

Can anyone see a reason for such a low power? motor pulls strong/compression is fine.
Matt was saying that the cams are not allowing it to breath! but i cant see the stock cams restricting it by that much, can it? something along the lines of, the turbo starts kicking in and starting the build good power right when the stock cams effiecency dies!

any1 care to comment, what do i start looking into?
BTW, the exhaust consist's of a full 3" turbo back, custom dump with blitz nur spec r cat back.
Also note that our dyno dynamics readings are always lower then the dyno jet readings.

Ive added a dyno sheet of the ~25psi run
 

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One of the first things you do to a JDM 2jzgte is ditch the 226 duration cams. Get a pair of HKS 264 cams and you will be set. That is your total problem right there.
 

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50-50 by weight

The water will cool the intake air more that the meth. We in CA only get 91 at the pump. I have been able to Run 22 psi and 16 deg . Useing Snows Performance Inj. 220 # pump and two inj. runing 11.90 on ET Streets. Remenber meth and water do not weight the same. By weight is the only one can get a 50-50 mix.

The best info I ever found is rbracing-rsr.com click on calculations-click on RSP
water inj calculator

You will get your answers
 

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Cams are definately restricting you,your engine can only flow some much with the stock cams thats why you are not making the power.Just because you have a large frame turbo does not mean you will see big Hp unless you have all the supporting mods to help it push the air through your head faster

1. change cams 264's or 272's
2. Bigger exhaust system will help too 3.5 or 4"

:)
 

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Moderator, l337 M0d3r4t0r
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I say #1 the tune and #2 the cams.

In my experiance with the 1jz cams going from stock to a special grind closer to 264's got me almost 60 WHP on top and allowed me to hold power right to redline (actually gained me 130WHP under the curve)

Anyways, I say eaither the tuner is pulling too much timing, you have a boost leak or something else is going on.

Even with cams i've seen people dyno like 700 WHP on a gt42 with 25 PSI!
 
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