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25DB Widebody Rsti

262282 Views 1272 Replies 108 Participants Last post by  r0bman
Lets get to the point.

Donor car: 2005 sti slightly modded.

Was fun while it lasted.

Fun in the snow.

And on the track.

Then some water happened along with a crazy idea and this was purchased.

and the FUN begins.


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Ain't this your home base server, remember it being an issue before, or you moved or something
Yes... its my box.. but I have not been taking backups.. so last one is from around 2018.
... reminds me to back up my shit meow. Been about that long or 2019
Ok.. I re-did all the missing pics as best as I could..
Didn't bother with screenshots of the tuning maps.. but if anybody does want to look at it.. just reply and I'll do my best..
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So.. we are off with some updates..
Lets start with the rest of 2021...

Did my first track day...

Meet the FIRM. Florida International Rally & Motorsport Park

How it went you ask ??? Well.. out of the whole day I had maybe 20min of track time..
Mostly doing runs back to the "paddock" to make a change and back out..
Just went too soon.. as I was getting knock left and right.

Lunch hour was as well, spent fiddling with the computer...
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After the fiasco of the track day.. it was time to retire the 8yo hard rubber.

Tire rack has really fast shipping..
2days after the order and this showed up...
A set of Hankook Ventus R-S4.
I've heard a lot of good things about the longevity and traction.. so this was the choice.

Picked up a welder too... As it was about time to start learning TIG.

This was my first attempt welding AL.. no prep.. no experience...

This was the result with some practice..

As a practice, I welded up few of AL, Steel and Stainless cubes. has ready to go and clean kits

It was now time to man up and chop up that Cobb exhaust.
I needed to weld up the holes around the cat and weld in the V-band.
I backpurged the pipe as best as I could..

Last but not least.. we got another member to our family..
No ride in the subie for him yet.. but he's working out the courage. Seems like the car is loud for him.

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Slowly catching up to current state..

As the center console had 3 different materials/colors it was time to fix that.
Disassembling was and still is a PITA.. but everything had to be taken off.

Almost as fluffy as alcantara.. almost.

Still undecided about the gear shift trim... so might do that one as well one day.

Oh.. and here is the doggie a bit older.. with a vintage Penguin Computing plush toy..
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hehe.. ok.. ok.. Next I'll post my yuge carbon mod too then.. :ROFLMAO:

Aww I miss the carbon
As promised ... carbon MOD update.

See unused hole

Some filing and some promised carbon.

Behold the carbon.

And the hole now has been filled.
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3 days of reading entire thread
Most of all, thanks remski for continuing to update thread to the finished product
Shows your dedication and attention to detail

what a car!

im going to send u a pm/dm (whatever it’s called now) about a ‘post build’ question
Glad you liked it..

I've read interesting journals over periods of days.. so trying to make this one entertaining as well..
Meet meth..

Misinformation leading to my mistakes .. so you dont have to repeat.

Lets start with rule #1..
AEM meth kits are shit.. (never had one.. but read so many bad things on the meth forums, so stay away from that one)

Rule #2
Some companies lie on pump ratings.
Given that most of them use the same Aquatec 5800, some rate at 160psi and same at 300psi...
~160psi would be the correct number.

Most meth kit mfg will say.. put the nozzle 6" before the throttle body..
This is wrong...
You need to put it as far as possible from the throttle body.
This gives time for the meth mixture (usually 50-50 with water) to cool the air and get absorbed.

Depending on effect desired its best to put it right after the intercoler. (that is if your intercooler is efficient or big enough to cool the air charge)
If your IC is not.. then you can put one after the turbo.
There are also ways to increase your turbo efficiency by spraying pre-turbo.

Here is a chart of possible nozzle placement.. (just missing the manifold location)

Best setup for knock supression is direct placement in the manifold in each runner.
This guarantees that each cylinder sees the same amount of the mixture.
Couple this, with the after intercooler nozzle(s) for best results.
You'll get the anti-knock properties from direct injection plus cooler air charge, which should also increase your knock threshold.

This was where the old 2 nozzles were.

Given this.. and the knock I was seeing with really low timing, it was time to put few holes into that manifold that I spent hours and hours polishing and cleaning up..

I've ordered a Prometh kit.. with a nice manifold and all..
Very pretty, aluminium with stainless nozzles...
or is it ???

The nozzles I ordered were about 1/2 the size of my Aquamist nozzles.
Given "the rule".. the smaller the nozzle the better the atomization..

Started testing, made some vids.. (thus crappy pics)

So for shits-and-giggles I wanted to see how this compares to my old Aquamist nozzles.
This is how they flow at lowest duty cycle...
If you pause for a second you'll see 4 jet streams..

Here is a pic of Aquamist at 50% duty cycle. (rated at 510cc and 440cc @160psi)
I've cricled the mist and the nozzle.. so you know.. you could see it...
(Oh.. yes.. the Aquamist at its lowest duty cycle still sprays a mist..)

And Prometh at the same DC. (rated at 240cc @160psi)

You be the judge now..

But wait.. there is more..
After seeing such shitty results from smaller nozzles, I've decided not to use them and ordered a new kit from Aquamist.
Putting away all nozzles Aquamist and Prometh back into a box..
(actually trying to return them.. but after restocking fee and shipping I'd get back $50, cant return the nozzles, just the manifold. So maybe at least they are good to water a veggie garden?)

After about a 1.5 months.. the Aquamist kit arrived from England.. yay !!!
Was so excited, and wanted to see how the flow compares to the Prometh.. as size wise they were pretty much the same.

Took out the Promeths out of the box.... to see this.

But wait.. there is more... (filter)

And more...

Even the nozzle itself had rust !!!
3 out of 4 nozzles didnt flow at all.. The one that did, was just dripping.

Now.. It would be unfair if I didnt check Aquamist nozzles.. so I opened them up as well.
(The rust spots you see on the cloth, are from cleaning the Prometh nozzles..)
As you see ZERO rust or dirt.

Here is an over all test with 3 Aquamists, ranging from 240cc - 510cc against a 240cc Prometh.
Pressure wise .. its just tap water.. at around ~50-70psi.

Here is why the Prometh is such an inferior product.
Despite the shitty atomizations pattern for its nozzle size.. its made from 3 different metals!!! (steel, stainless, aluminium)
The spring and filter arent even stainless !!!!

Now.. thank you gut feeling.

Back to install.
Here is the after intercooler nozzle. (to reduce IAT)

Aquamist manifold.

And the individual manifold nozzles.

And here are the results.
On average there is a drop of about 15-20F.
Was expecting a bit more.. but it will do for now.. (maybe will go to an even bigger nozzle in the future)
Notice how the IAT sensor lags...

Ah yes.. had to edit..
Because I forgot rule #3.

Always, always check your pressure after installing the nozzles.
Mine was at 130 psi with 4 nozzles !!!
Bumped it to 200-210. (as per Scott)

Got this gauge from
I've picked the owner's brain quite a bit.. so the info you see here is from him.
Thanks Scott !!!

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So much info, love it. Sad on the crap quality that $50 sounds good now lol :/
So.. a real fucking sad day...
Felt like I needed to vent somwhere.

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Sorry bro
Lots of times people what try to make you feel better with their own story…….IMO that makes the frustration worse for the said person
Failed solenoid or wiring or solenoid mgr?
(I’m not meth injection expert by any means…..just feel 4 ya)
Looks like it lost trigger signal from the cams? I hope the motor is ok!
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