ej20t in jet boat. need advice??

[rwcoop]

Ok, Im from New Zealand and i think our subys are a bit different but ill try yas anyway.
I have a 1990 single turbo rs legacy engine in my jet boat which is water/air intercooled. Its all standard outa the car with the standard car computer and lume (4 plug)
Now heres the big question. I am wanting to put in a later model sti engine in its place but am not wanting to rewire the boat.
So If I get a late model STI long block, and chuck my dirty old 1990 inlet manifold on it, will this work and will my old ecu run it.

OK my next question. Apparantly up to V2 stis had the same wiring lume, so this should fit straight in. Would this engine be much of an improvement of HP. and hw much better are the later model sti engines.

Look forward to replys

[555BCTurbo]

The V2 Sti motor is very similar to your current one, with a different turbo and a bit of ECU tuning...honestly, I would say track down a TD05-16g turbo and a V2 ECU and you should be good to go for about 260+ hp.


btw...I was born in Timaru, and have family in Auckland still

[rwcoop]

Ur engines must be different. Coz thats def not the case here as the rs engine is closed block as opposed to oppened deck on the sti.
And im sure the sti engine has forged pistons etc and know for sure they have differnt heads etc??
Classic that u were born in NZ!!

[555BCTurbo]

Ur engines must be different. Coz thats def not the case here as the rs engine is closed block as opposed to oppened deck on the sti.
And im sure the sti engine has forged pistons etc and know for sure they have differnt heads etc??
Classic that u were born in NZ!!

The Version 2 engine is actually closed deck as well, as it is an EJ20G just like the engine out of the RS Legacy. To get forged pistons you need to step up to an RS-RA motor or an STi-RA motor...Now, with the later versions, the engines did become open deck, but if you stick with a 2 liter from the earlier versions of the STi you would be good to go.

[Matt Monson]

Ur engines must be different. Coz thats def not the case here as the rs engine is closed block as opposed to oppened deck on the sti.
And im sure the sti engine has forged pistons etc and know for sure they have differnt heads etc??
Classic that u were born in NZ!!

The Version 2 engine is actually closed deck as well, as it is an EJ20G just like the engine out of the RS Legacy. To get forged pistons you need to step up to an RS-RA motor or an STi-RA motor...Now, with the later versions, the engines did become open deck, but if you stick with a 2 liter from the earlier versions of the STi you would be good to go.

Actually, whether or not a v2 engine is closed deck has been a point of fairly constant debate over the years. There are members on NASIOC who claim to have opened up v2 engines and found both open deck and closed deck engines. I am currently in possesion of a v2 non-STI engine and I am pretty sure it's open deck, even though I haven't opened it up yet. This coming weekend, I will be tearing into a v2 STi-RA engine, which my preliminary inspection also suggests is open deck.

But at the end of the day, it's all really a mute point. As far as I am concerned, it doesn't make one bit of difference if it's open or closed deck or not. They are both quite strong and can easily support 300+ chp.

If it were my boat, I would start shopping for a later engine complete with turbo, as well as the ECU to go with it. Just be sure that it is a Japanese ECU from a manual transmission sedan. Wagon ECU's will be lower power in the same neighborhood as the AUS spec vehicles. And auto tranny ECU's are also not as powerful. An STI ECU would be fun, but a non-STI ECU is nothing to scoff at.

Or... If you are feeling adventurous and want to explore tuning the thing yourself, you can look into an Autronic plug and play replacement ECU. That would allow you to tweak your boost, fuel and timing maps and make significant gains in power even if you didn't change your engine...

Lastly, if you go shopping for another engine, and want to keep your current ECU and wiring, any '94-98 WRX engine will be a direct replacment and allow you to continue to use your current intake manifold. '99 was the first year of the new manifold bolt pattern, and anything from '99 and later will require you to use a different manifold and intercooler...

[rwcoop]

mm, is there such thing as a wrx RA thats not STI.

Just was talking to a guy thats got one for sale, and if theres no such thing, well I could be onto a winner as he obviously doesnt know what hes got??
Its got a 5th injector but is not red top??

[Matt Monson]

There were STi's and RA's and STi-RA's. There were very subtle differences between them, which is part of the reason for the ongoing debate on whether or not they have closed deck blocks. The only ones that I am almost 100% sure were closed deck are the STI-RA's. Anyways, only an RA model would have a 5th injector. And the crinkle red on the manifold wasn't actually used until v3 and 1997...

[206er]

do you use the lake water for your intercooler?
got any pics of this boat? sounds cool.

[rwcoop]

Yeah I do use the river water. Is the ultimate really as the intercooler is always stone cold.
How do you post pictures on this web board thing??
Or tell me ur email (if i dont find it and will email u some pics)

Dont be fooled by the red inlet manifold, I painted it!! TRY HARD

[Legacy777]

You need a webserver to host the pictures.

Check out this thread for info on setting something up.
http://bbs.legacycentral.org/viewtopic.php?t=17062

Or you can email them to me, and I can host them.

[rwcoop]

yeah couldnt get that to work aye, it would email me my password.
Might get u to host them if ya dont mind. How do u get the photo by your name?? Mostg ppl seem to have them

[Legacy777]

Email me the pics jlegacy(at)surrealmirage.com

Admins & moderators are typically the only ones with images. There are a few other people with special images, but that's it.

We don't allow avatars due to people abusing them in the past.

[Jaxx]

honestly swapping in another engnie is probbaly a bad idea unless you plan to change the lome or go standalone

i have the same engine as you
running bigger (550) injectors, a td05 and a standalone

if you have good compression i would consider looking for a 93-96wrx (mt) ecu and turbo (tdo5) this should add 40-60 hp (depending on which model you started with) .. from there i would hook up a wideband and add a boost controller till you start to go too lean or hit boost cut