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One...because they're in it to make money, and by charging you to replace the headgasket....they make money.


Either way, I doubt that stuff works.


in theory i can see it working, espcially with a pin hole leak. The thing is pin hole HG leaks dont stay pin hole leaks very long.

The other part i am suspisous of is the ceramic part (it syays that on the label). Ceramics are known for maintiaing thier dimensions in major temp deviations, where as a HG has to expnad and contract with the engine.

Als the ones on the testimonial pages tend to be cast iron enigines or blocks.



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This is an excerpt from a rather wordy diatribe from Mike at SPD in '98 regarding the suitability of the 2.5 for aftermarket turbo kit: (he voted NO)


**** ******!


"There is obviously a ground swell of interest (if not actual cash) in

finding some way of turbocharging the US engines. The fact remains that

although the redesigned K series turbo motor cases have an open deck

design, it does not follow automatically that the EJ25G DOHC engine used in

North America is cleared for take-off. There were and remain additional

issues to consider. Simply put, when first asked about turbocharging the

2.5, the open-deck issue was first on the list and made further discussion

to my mind pointless. Lest we give an answer in search of a question, let's

ask this question: Does the 1998 2.5 RS DOHC or 1999 SOHC engine have

common design features with the open deck or closed deck turbo motors? Here

is the information I have been able to assemble. It may not be the final

answer, but it is what I have been told.


We know that the issues that resulted in the open-deck K series motor were

answered as a result of lower demands being placed on the engine due to

changes in racing rules and from actual design changes made by Subaru

engineers. However, one can not assume turbocharging has been evaluated in

the EJ25 engine. The following remarks were made to me by a Subaru

engineering person, who should remain anonymous. They stated that the 2.5

DOHC engine was a "damn the gas mileage, give me some torque" responce to

US market needs and is a "stretched" design specification engine. As a

"stretched" design, it was produced with no consideration of additional

mechanical/thermal stresses of high power and/or rpm. For the sake of the

argument, its power output at 165hp is as near its design limit as a "K"

series WRX engine is at its 280hp output. In contrast, during the same

conversation, the closed deck Japanese EJ20G turbo block and the older

91-93 American closed deck EJ22 turbo block were considered "bullet proof".

This person had no personal knowledge of open deck WRX engines at the time

we spoke.


It was specifically mentioned to me that the thrust bearing area is known

to be marginal WHEN CONSIDERING MORE POWER. Note the emphasis. Not that the

engine has a design problem - that was not the point. The point was if one

were to take the engine out to some big torque and horsepower numbers, the

bottom end was a limiting factor. This implies that the bearing webs in the

case would "walk" under the torsional loads of large power output, where at

the designed 165hp this was simply not an issue. This type problem has been

true for many engine designs over the years, by the way. Second, the

cylinder head and water jackets were not designed for the thermal stress of

turbocharging. Third is the thickness of the cylinder wall. This is a

particularly important issue when it comes to the head gasket area in an

open deck design. From the brief conversations I have had with Subaru staff

it was made clear that no special attention was paid to potential stress

from high output in the design process of the EJ25 DOHC engine. In

contrast, the design of the EJ20G Turbo motor saw every area of design was

gone over in the "WRX-RA" series engines with a mind to 400hp output. This

is the most important point that one needs to know when assessing the 2.5

motor. Just where are the limits? I was left with the impression they are

lower, rather than higher than one would assume from the rally heritage of

the turbo EJ series Subaru boxer engines.


What else can I say? I was sitting there having this conversation about the

RS 2.5 engine and feel it should be made public. It does not mean one can

not supercharge or turbocharge the 1998 EJ25 engine to a nice 250hp. It

just means that SPD Tuning Service is not going to develop a kit for this

purpose, as I will also very seldom bet on less than a pair jacks when

playing five card poker. The odds are not in my favor. Especially with the

typical urge, myself included, to turn up the boost.


In the same conversation, I was told that 1999 2.5 SOHC engine has

addressed the bottom end concerns. Of the two engines the DOHC 98RS and

SOHC 99RS, I was told the SOHC engine is a much stronger engine. In

driving the SOHC engine, it does seem to be a smoother, tighter engine on

the top end, indicative of a stronger case, among other changes. The new

1999 EJ25 however, along with a 1.8 and a 2.0 version, is a family of

"lean-burn" combustion chamber/engine management engines. I do not know how

the this aspect will play into the high pressures and temperatures of

turbocharging, nor if the valve and seat material is up to the higher local

temperatures seen in turbo motors. So again, spending the big money and

developing a reliable turbo setup remains an open issue for me. On the

other hand, I suspect that if we see a turbo motor, it will be a 2.X SOHC,

non-intercooler engine from this new family, with the necessary engineering

changes. This part of the puzzle is starting to make sense, as it is

unlikely we will see the EJ20K with the extra cost of the DOHC heads and

intercooler. The fact that we have only 92 octane gas would effectively

limit this motor to 220hp on a hot, dry day, where a 220hp 2.5 would be

much less near the edge."

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I am looking in to the same thing for my GT. Let me know if you get anywhere with that.


you first. im still laid up with from back surgery and some leg paralysis for the rest of this year.

Say anyone on long island have an SVX i can try on for size?




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there is a guy that sells them on ebay complete with ecu and harness.

Which leads me to the question, how do you get parts for them.



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i soooooooooooooooooooooooooooooooooo want an svx, but i need to make sure i can get my leg that wont bend properly into one first.



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