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chevelle100
08-29-2005, 12:28 AM
What are some good turbo kits for the ej engines? Are there any webpages to help you make one yourself? Thanks.

FalconRS
08-29-2005, 12:39 AM
Might be better to ask in the aftermarket turbo forum, over here it's mostly us guys looking to make power without resorting to hairdryers. :)

Lethargic1
08-29-2005, 02:24 AM
I think most people will tell you to do an engine swap rather than building your own turbo engine. There are usually pretty good debates on this, look around the forums a bit and you'll find them.

Jesse00
08-29-2005, 03:22 AM
its not really a debate, but its not very wise to turbo a rs engine. There not much you can pull out of the sohc ej25. so thats why people recommends engine swap over turbocharging the original engine.

Dead Man Sliding
08-29-2005, 04:08 AM
You can turbo anything you want. The key is not to shoot for a high number (why does everybody want 300 so badly?) and keep it real. Generally, on any old 4 cylinder, you can thro together a system on the cheap that may only get you 30-40 peak hp, but a whole bunch under the curve. It'll drive like a whole different car and give you a new forced-induction tuning path to begin down.


Go to uniquemotorsports website. He's got some good data on a grungy turbo setup that works.

Keep in mind that when you boost *any* engine by *any* amount, you are putting more stress on it. Prepare for the worst and hope for the best!

HondaH8er
08-29-2005, 01:40 PM
The AVO kit at www.rallitek.com is a very nice kit, sounds like everyone who has it likes it a lot, and it isn't causing problems. But the things to think about are that once you turbo the NA EJ25, you'll be spending about as much as a swap would cost (for a good turbo kit, anyways), and it will be giving you a bit more power than a stock EJ20T, but the turbo'd EJ25 will be at it's peak, with no more room for more power, while the WRX swap will have lots of room to grow. I was debating these two options myself, and decided that the swap would be the best way to go. Especially now, with the new WRX's coming with 2.5L turbo plants.

chevelle100
08-29-2005, 02:01 PM
What is the "wrx swap"? Which engine is that?

Matt Monson
08-29-2005, 02:20 PM
You can turbo anything you want. The key is not to shoot for a high number (why does everybody want 300 so badly?) and keep it real. Generally, on any old 4 cylinder, you can thro together a system on the cheap that may only get you 30-40 peak hp, but a whole bunch under the curve. It'll drive like a whole different car and give you a new forced-induction tuning path to begin down.


Go to uniquemotorsports website. He's got some good data on a grungy turbo setup that works.

Keep in mind that when you boost *any* engine by *any* amount, you are putting more stress on it. Prepare for the worst and hope for the best!

I think you've got the right idea here. The thing to keep in mind is that there is a huge difference between what an Ej18 can take versus an Ej25. The Ej18 has a much more solid cylinder because of the smaller bore, and has way taller top ring lands, and can suffer a fair bit of detonation before failure. The Ej25's on the other hand, lose pistons real easily if you detonate, and under high boost, the cylinder walls and crank girdle will walk...

I have a pretty complete factory based kit that just came off a car. We were running the identical set up as SubaChad (uniquemotorsports) with an Ej20G bottom end with Ej22 heads. The exception is my stuff is all factory from an EJ22T powered Legacy Turbo. This would require a turbo crossmember. What Chad is doing with custom pipes allows him to use his stock crossmember...

Matt Monson
08-29-2005, 02:21 PM
What is the "wrx swap"? Which engine is that?
Umm, that would be a WRX engine? :huh: It is the EJ20 and it came in various flavours over the last 10 years. EJ20G, Ej20K, EJ205, EJ207. Hit the conversions forum for more details...

chevelle100
08-29-2005, 03:14 PM
I meant the model number. So, its the ej20t?

svek
08-29-2005, 03:22 PM
"What if I want it use my 2.5 as a hot gas generator?

We see two trends developing. Superchargers and turbochargers after market kits for the 2.5. The 2.5 DOHC engine is a "stretched" design engine and is not recommended for more than 235hp. The cases of this engine are strong enough to run for ever at 165hp, but are not designed for 300hp. So, until proven otherwise, we are recommending that the DOHC 2.5 keep its stock pistons and compression ratio and be limited to about 240hp on pump gas. Supercharging is idea for this low pressure boost, 5-7 pounds scenario.

The weakest link in the 2.5 motor is the crankshaft connecting rods. The end caps are too thin to take a lot of stress. The stress can be rotational or due to high power output. We recommend miving the red line down to 5200 rpm when going to 220hp output levels. This will keep the bottom end out of harm's way. As many of you know a 2.5 engine running flat at 130pmh+ lost a rod bearing this spring. Like, what did we say about this before, guys?

For those wanting the "Big Power", as a friend of mine calls it, these US engines need a change of pistons to lower the compression down to 8.5:1 or so. Then is is fairly easy to get 300hp from the the 2.5 SOHC engine with some hope of reliability. We are holding our breath on the reliability of the 2.5 DOHC at these higher outputs. As I said earlier, lower your red line and install an oil cooler. Do not get greedy with the boost. All boost junkies suffer the same fate: engine damage sooner or later.

There are, as of July 1999, projects coming into place. Several customers report satisfaction with Minnam's turbo kit. I have been told the fit and finish is good and aftersales service is not as good as some would like. The motors sometimes "code" and Minnam is working on fuel and timing tricks to keep this to a minimum. Rimmer Engineering has a kit that now fits under the hood of an Impreza and is shipping kits slowly. These run flawlessly at about 220hp. "


quoted from mike @ spdusa

Matt Monson
08-29-2005, 03:31 PM
I meant the model number. So, its the ej20t?
I was just playing with you. I listed the manifestations of the Ej20 as it was delivered in the WRX's over the last 12 years. There is no such thing as an EJ20T. Like I said, head over to the conversions forum if you want to learn the nuances of the different models. The engine has changed in many ways, some good, some not so good, in it's lifespan. Just be wary of any importer advertising EJ20T's.Find out the exact specification of the motor in question. 90% of them came out of Legacy turbos, which doesn't make them bad motors. I own two Ej20G's from Legacies. But do your research before buy and find out what is going on...

Svek,
That article from Mike Shields is 6 years old, and the phase II engines had just come out. While his comments pretain to the phase II Ej25's, there are some very well set up phase II Ej25's running turbos in the 8-12psi range with 50k mi plus on them. The key to the formula is engine management. You have to spend the money to get a good ECU and tune it on the dyno. Butt dyno tuning has been the death of many an EJ25.

Lastly, with such availablity of Ej257 bottom ends. Most of the guys who were running NA Ej25 bottom ends, have switched over to the turbo block with it's beefier rods, semi-closed deck design, and the all important lower CR. With NA EJ25 heads on an Ej257, you get down to around a very nice and safe 8.5:1 CR...

svek
08-29-2005, 03:35 PM
Svek,
That article from Mike Shields is 6 years old, and the phase II engines had just come out.

yah i noticed that too haha. still good thing to read up on. i

chevelle100
08-29-2005, 03:38 PM
So, if I were to do a conversion with an american wrx motor, what's the model number?

Matt Monson
08-29-2005, 03:51 PM
Ej205

chevelle100
08-29-2005, 03:58 PM
Where can you get one?