nipper Posted July 11, 2006 Share Posted July 11, 2006 Legacy777 said: 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. nipper Link to comment Share on other sites More sharing options...
blitz Posted July 11, 2006 Share Posted July 11, 2006 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." Link to comment Share on other sites More sharing options...
blitz Posted July 11, 2006 Share Posted July 11, 2006 Here's the URL if you want to read the whole thing. http://legacycentral.org/library/literature/mike_turbo.htm **** ******! Link to comment Share on other sites More sharing options...
nipper Posted July 11, 2006 Share Posted July 11, 2006 blitz said: Here's the URL if you want to read the whole thing. http://legacycentral.org/library/literature/mike_turbo.htm **** ******! *note to self* JDM twin turbo 2.0L for Blu. nipper at least it explains the reasons for the twin cams. Link to comment Share on other sites More sharing options...
rlsimpso Posted July 11, 2006 Share Posted July 11, 2006 I am looking in to the same thing for my GT. Let me know if you get anywhere with that. Link to comment Share on other sites More sharing options...
nipper Posted July 11, 2006 Share Posted July 11, 2006 rlsimpso said: 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? nipper Link to comment Share on other sites More sharing options...
rlsimpso Posted July 11, 2006 Share Posted July 11, 2006 Hmm... new roof or put one of these in my Legacy: http://cgi.ebay.com/ebaymotors/SUBARU-EJ20-TWIN-TURBO-ENGINE-JDM-DUNE-BUGGY-EJ20TT_W0QQcmdZViewItemQQcategoryZ33615QQihZ007QQitemZ170004102732QQrdZ1QQsspagenameZWDVW Damn, deprecation is a ***************. Link to comment Share on other sites More sharing options...
rlsimpso Posted July 11, 2006 Share Posted July 11, 2006 This one is on NJ, thats kinda close: http://cgi.ebay.com/ebaymotors/1995-Subaru-SVX-LSi-Coupe-2D-150k-miles-green_W0QQitemZ270005906957QQihZ017QQcategoryZ31871QQssPageNameZWDVWQQrdZ1QQcmdZViewItem Next closest is Florida:-\ Link to comment Share on other sites More sharing options...
nipper Posted July 11, 2006 Share Posted July 11, 2006 rlsimpso said: Hmm... new roof or put one of these in my Legacy: http://cgi.ebay.com/ebaymotors/SUBARU-EJ20-TWIN-TURBO-ENGINE-JDM-DUNE-BUGGY-EJ20TT_W0QQcmdZViewItemQQcategoryZ33615QQihZ007QQitemZ170004102732QQrdZ1QQsspagenameZWDVW Damn, deprecation is a ***************. 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. nipper Link to comment Share on other sites More sharing options...
nipper Posted July 11, 2006 Share Posted July 11, 2006 rlsimpso said: This one is on NJ, thats kinda close: http://cgi.ebay.com/ebaymotors/1995-Subaru-SVX-LSi-Coupe-2D-150k-miles-green_W0QQitemZ270005906957QQihZ017QQcategoryZ31871QQssPageNameZWDVWQQrdZ1QQcmdZViewItem Next closest is Florida:-\ i soooooooooooooooooooooooooooooooooo want an svx, but i need to make sure i can get my leg that wont bend properly into one first. nipper Link to comment Share on other sites More sharing options...
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