The situation is thus: this '91 SS ran great when I purchased it and drove it from Ogden, UT back to Elko, NV in or around 2008.... where it sat for a long time, rarely used. At one point, a family member who had access to the keys decided that he needed to borrow this car for some errands or something, and took it without asking (or checking fluids, this was the killer!)
The car apparently was overheated quite severely, I can only guess it had a coolant leak and had emptied itself as it sat for months before it was driven. When I tried to start the car next, after this incident that I was unaware of (my only indication that the car had moved is that it was parked in a different orientation / position), it felt like the engine was freewheeling and I assumed the timing belt had broken or something. When I finally towed it in to have the timing belt replaced, the mechanic informed me it had 0 compression on 3 of the 4 cylinders (one cylinder was at 122psi, rest at 0) and the timing belt was in decent shape. He then proceeded to tell me that my only option was a new engine. At this point, I told him to cease all work and paid him for the diagnostics up to that point and got the car the hell away from his shop. Replace an entire closed-deck engine to fix what is probably just some rings and a headgasket? Yeah, I don't trust you anymore with my EJ22T.
So, I finally had this car delivered to Oregon to Accelerated Automotive and the owner is really interested to build up this EJ22T with me. I told him I would look into the best options for forged internals on this forum, as the collective experience on Legacy Central is ridiculously awesome. Right off the bat, he suggested Wiseco pistons and Eagle rods as they are available for my engine, and I'd seen many members post about using this combination with good results. However, I'm a bit unsure as to exactly how to spec out what I want -- I've got zero bottom-end experience.
I've done some searching on the board and found many members running forged internals, but what I couldn't figure out was how they specified what they wanted or even how they arrived at those conclusions. I am, for all intents and purposes, an engine n00b and need some education.
I suppose my first question is, what internals should I be looking at replacing while the block is apart? Wiseco pistons and Eagle rods, sure, but that's about the extent of what I've learned so far. I've seen some posts mentioning ARP Head Studs and ACL Bearings, are these worth getting? (and why?)
I understand our stock 2.2 crank is already forged and should be fine for usage with other forged internals and high HP setups -- is this accurate?
Now, what about displacement? I am assuming that if I leave the bore and stroke alone, I will have the highest reliability factor. Is this the case? Is the EJ22T worth boring and/or stroking at all when building up with forged internals for big power (450 - 500 HP range? Higher? I realize my puny 5MT will not hold up to these power levels, and will source a 6MT when the time is right).
Am I correct in assuming I have no special specifications to give to Wiseco and Eagle if I leave the bore and stroke alone? As in, I can just order a set of pistons and rods designed for the EJ22T with no other parameters provided? Or are there reasons to specify slightly larger or different shaped pistons and/or rods? Are there different rod designs I need to look into or just stick with the stock shape?
Pistons, well, I know if the surface of the piston changes shape then the compression ratio will be affected somewhat. I'm a bit torn on my target compression ratio; should I stick with the stock compression ratio, drop it, raise it...? The 600 HP STi my mechanic has is running 25lbs of boost @ 9:1 CR!! I had always expected a big turbo to be matched with a lowered CR like 7.5:1 or 7:1.... is this just for safety with a bad tune or what?
What about rings? Any special brand, just get Subaru OEM? Have Total Seal rings been correctly manufactured for the EJ22T yet, and are they worth looking into? What is important to selection of a piston ring?
I also would like to maintain the SOHC stock heads, albeit ported / polished / valve job'd, as well as the "non-interference" characteristic of this engine. I want this car to, in the end, be streetable and as reliable as possible. I'll get groceries with this thing, and drive it to work, because I like my errands and commutes to be as enjoyable as possible!
I don't see the need for the added complexity of a DOHC swap, what with all the difficulties involved and in the end I still have 4 valves per cylinder... I plan to, as in this legendary thread, simply replace the valve springs with titanium springs in my SOHC heads to prevent valve float at higher RPMs.
For the turbo.... .well, my VF36 twin-scroll ball-bearing turbo is indeed destined for my '94 SS. That turbo is good for up to about 400 HP and that's about where I'll be happy with my '94, so I need to choose another turbo for the '91 build with more power capability. Since this will be a largely custom job anyway, I suppose all bets are off; I don't need it to match the stock turbine flange, although it would be nice if it did. Selection of a turbo is not for this topic, though, and as such I'll start a new thread in the Turbo category with a link to this thread for reference. EDIT: viewtopic.php?f=2&t=52206 <--- here is the turbo thread for this build
More immediate is figuring out exactly how I want to handle this engine rebuild, so I can get parts ordered and get the process started.
Please, discuss -- any suggestions or criticism welcome. I value the board's consensus above all else when planning this build, you guys have never steered me wrong and I always learn a lot from the process. I openly admit I have zero experience with engine internals, although I do know how it basically works. A little knowledge is dangerous, though, so I'd rather be fully educated before continuing along this path.
Thanks!
