EA82T upgrades

[Dubcrazy]

Just rebuilt my Ea82T from top to bottom with everything standard bar the injectors(60cc bigger) and having the crank,rods and flywheel balanced and lightened. I run 9psi and that returns 119bhp at the wheels(microtech lt10 ecu) and i am quite happy with it but as always i have the desire for more!!

speaking to a few people and looking on the net the first thing i will do it a intercooler and a duel stage boost control but i have also seen and had suggested a water injector fitted to the inlet manifold? i get the basic idea behind this but has anyone done it? does this give u the option of running the boost higer again as the water brings the core temp down?

I would like to drop the boost back to 7 for day to day driving and only use the second stage every now and again ) I know i can fit bigger turbos but thats a major headache for me as some of u know or have seen i run this engine in the back of a Baja and the area the turbo is fitted is very tight indeed and i think it would be a major to go bigger. so if i can get some gains other ways while still keeping the car reliable(its my daily driver) i would be happy.

any ideas on what i have said or totaly new ones?



thanks

steff...............

[phillatdarwin]

is that engine u have is it a japan inport hi out put ?
with a inacooler u can go a bit hire with the boost then what u are running .
i wood say from what i have read on hear u can run 9psi all day with no proloms that is if u are running a inacoler

[discopotato03]

The standard turbo is a choke point in these engines and the header is set up for the tiny turbo .
It pretty much goes like this .

Fit small turbo so that it makes boost low in the rev range .
Fit header that isn't big or well designed because tiny turbo doesn't care .
Fit low compression ratio pistons because this gets around detonation issues .
Run advanced timing at light loads to pull up off boost torque/throttle response .

To make major changes to an EA82T's power characteristics is going to mean better manifolds and turbo - better meaning more modern and better flowing . From the factory the later Vortex "spider" inlet manifold is as good as it gets .
From what I can find out the TWE type header exhaust manifold appears to work well by having more even engine pipe length and diameter .
There not a whole lot you can do with the factory turbo other than in theory running a VF10's turbine housing and converting to EJ type up and down pipe flanges . The ultra rare factory 15R turbine housings are unobtaenium so the VF10's EJ flanged 15R housing is probably the next best bet . Far better thought out casting with a larger waste gate flat valve . The EA82T type turbine housings are very restrictive in 12R and 15R sizes are are also prone to cracking .
I don't see why if you made a custom up pipe , even for the std header , you couldn't have the turbo in the std position .

To have it work properly with today's pump fuel the compression ratio can stand to be better than the factory 7.7 to 1 . Due to a typo my came out at just over 8 when ~ 8.5 + was the ask . If I could have my time again I would have looked into modifying NA 9.5 pistons and tried to get it to about 9.0 .
To have the higher CR work without detonating to death you have to improve the header/turbo/the complete exhaust system and be conservative with boost pressure . Intercooling often makes up for the higher CR in an otherwise std system , the higher CR makes for better part throttle torque and fuel consumption and throttle response is generally better as well .

Going down the road of pushing up boost pressure doesn't work long term on most production engines . Generally people don't understand that when you increase boost pressure you also increase exhaust gas temperature and pressure and the engine was not designed to cope with the extra heat and pressure . These dinosaurs first saw the light of day in 1985 and metallurgy was not what it is today so tread wearily .
More current thinking is ball bearing turbochargers because having a lower friction bearing system means they don't have to be as small on the hot side to be responsive and with less exhaust gas restriction .
Exactly the same principles work on EJ20 turbo engines , most of them have garbage exhaust manifold systems and turbos that suit them . Mostly they have more modern heads/inlet/engine management AND intercooling . On paper the extra 200 odd cc's should only make up 10% of the difference .

Stu Wilkins told me that in the late 80's the best of the local legal RX turbos made about 190 fragile horsepower with std manifolds/best OEM EA82 spec turbo/long period cranky choppy terrible to drive camshafts - and NO intercooling .
Without race reg limitations I don't see why you couldn't have a nice to drive 160+ Hp but by the time you modernise everything you've spent a lot of money . Same deal with EJ turbo engines , they just start out with more of the goodies and much better heads .

A .

[Gannon]

Keep it simple and all should be ok.

Start with a upgraded exhaust manifold, maybe one of XtremeRX's Power Pipes


A WRX TD04 (with the above manifold, should net similar boost threshold to the factory turbo) or a GT Forester TF035 (which will bring boost on earlier at expense of top end flow)
These two turbos are the easiest to come by, usually less than $200 on ebay


A water to air intercooler to keep your inlet temps down


And a free flowing exhaust of 2.25" of 2.5" and a well made dump pipe and hi flow cat converter


These mods, along with your fresh engine and tune-able ecu, should net you some decent power figures

[phillatdarwin]

so this is what i have to do to get my ea82t to go hard .
Or as hard as it will go with out going bang .

[ORX-18]

Stef, Come down the road and see me, I destroyed 3rd gear in the GTR on sat night at the motorkhana just before u showed up so now i have time to spare, ill let u in on a few little secrets and show you what ive done. I have a few spare manifolds and heads kicking around if u wanna have a play with porting and i think i have a VF-10 on a manifold somewhere as well, gimme a buzz, ill PM u my number

Cheers AL

[spike]

you mentioned a water injection into the inlet manifold??
the last thing you want in there is water obviously. for a subaru i would suggest a water to air intercooler to make the air cooler and more dense thus more air per bang.

[twilightprotege]

water injection is really good actually!!! it's obviously a very small amount, but it greatly reduces the intake temps (the mix should be 50/50 water/methanol), increases overall octane by a lot, and thus adds a lot of power potential

[GOD]

increases overall octane by a lot

How? Water injection reduces risk of knocking, but I'd have thought that's more to do with lower temps and no hot spots from coke buildup?

Dane.

[twilightprotege]

it's because water has an infinate octane - this is why it reduces the risk of knocking. 50/50 water/meth is better than water alone - makes the temps a lot colder than water alone

[GOD]

Water has an infinite octane rating (not infinite octane), because it can't possibly detonate.

Got any references that discuss this? Still sounds a bit like the wrong path towards the right conclusion.

Dane.

[twilightprotege]

yeah octane rating - that's what i meant.

have a read through http://www.snowperformance.net/

[Gannon]

I wouldnt worry about water injection in an EA82T until you have run out of other ways to make power reliably.

You need a high pressure pump, an injector and a controller. I looked into it when i had my EA82T and there is a lot of work in it. Id get everything else done first

[fredsub]

i'll second that,
Shurflow pump $100+
Injector $90
valve solonoid $75
IIRC
plus its a hassle coming up with an appropriate water storage...
Then controller needs to PWM control the pump, switch the valve on/off,
ensure it only starts running when engine temp is normal,
activate when boost (map signal) / and or rpm or TPS position.
I started off with an analog controller, and used it for quite some time. then went digital with a PIC micro. But during development of that got a fire and end of car fun, so its unfinished, fortunately i still have all those bits because at the time it was off the car and being tested on the bench.

it also allowed me to alter the fuel map to use less fuel under boost, fuel that is normally just wasted just to keep things cool,
so in this regard water injection can be quite a fuel saver, surprising quite a large amount of water too. 1.5lt water for a 90km journey, always a hassle to lift bonnet
and refill....

Anyway its not easy to get right, but when it is, wow. I wasn't using an intercooler, so you can imagine the effect was pretty good.

[Gannon]

This is what i was looking at when i had my EA82T

I found a small diaphragm pump capable of 80psi at 2.6Lpm, i was gonna use a kit based water injection controller from autospeed.com, plus a 20l tank mounted in the under floor compartment in the back of the car.

But the more i looked into it, i needed special injectors for water, or a nossle capable of a certain flow, but to provide a mist at a certain droplet size. It was complicated, and i would have to upgrade to programmable fuel injection/ignition to reap the full benefits of increased ignition timing and leaner mixtures

[steptoe]

Julian Edgar of Zoom mag fame and now autospeed, or one of his mates, used a fogger jet (sold for chook sheds of huge proportions) on a Subaru application some ten years ago when the exchange rate was a US dollar cost us two oz dollars so the sureflo pump was $200. He also used a pressure switch from a washing machine for the switching duties. I don't recall anything real techo about his application, just basic and got the job done.
I salvaged some big heatsinks from an old Akai amplifier wondering if thy'd do anything on the alloy intake pipe on my EA82T