Been reading 'til my eyes cross, but I think I need some more current help.

I've pulled my motor but haven't dug all the way in yet to see exactly what I need. ( http://forums.nasioc.com/forums/showthread.php?t=948330 for current details) Pistons at least.

I know I'm adding forged pistons/ new wrist pins. And perhaps rods/bearings. After that... what is the order for required upgrades as power increases. I'm trying to get an idea of what I can afford vs. time the car is down (the longer it's down the more I can afford, so it's a patience test really.)

I plan on pulling the car out with about the same HP it had (400+ crank tuned poorly by me), but I want it to be much safer and I want it to be capable of higher numbers eventually. I'll try to get it tuned (a real tune at TopSpeed) to a good 450-500 crank HP, but I'd like it to be safe still approaching 600 crank in the future (with additional mods to support if needed) without opening the engine again.

I don't feel the need to make more high-rpm power or to raise the rev. limit. I don't feel comfortable at 7000 as is. But I'd like to have the heads gone over to improve flow.


With this strength/saftey goal, what pistons? Cobb? CP? What rods? Is the stock crank OK to 600 chp?

And for power improvement with the current setup (aiming to go from the 400+ untuned to closer to 500 tuned). Stock valves and springs? TGV delete help any? And a cam-set that's happy from 3500-5000? Where would I send the heads for a once-over?

Anyone know of a nice rebuild kit that's available? Bearings, rings, gaskets etc...? Or should I piece-meal?

Dang that's too many questions. :p Basicly: How would you rebuild this motor?

Thanks

And to keep the first post from being too long and annoying. I'll put my bolt-ons down here:

Current add-ons: (with near future plans to help the 450+ CHP goal)

Deadbolt: Kong II (with helper spring) (plan on going with a SZ or Green.)
Turbo XS Stuff: UTEC, Tuner Pro, FMIC (stock IC spray moved with it), recirculation valve (100% recirculating), Shorty intake, Dual Stage Boost Control (UTEC actuated)

Perrin Stuff: 816cc mod-stock injectors, Fuel Rails, Catch Can, Lightened Crank Pully

GPmoto: Equal length headers / Up-pipe (plan on crucial treated stockers and BPM U/P), MAF hose

Cobb: AP for CEL and Speed limiter defeats (Plan on adding ST)

Borla: Hush Catback

QTP: Electronic Exhaust Cutout

Walbro: 255 LPH fuel pump

3" Bellmouth Down Pipe. (Plan on getting Perrin or Invidia V-3 divorced)
Home grown: GMC Cyclone Boost control solenoid, Tooph-DM turbo inlet, 2.5" steel tube & silicone connections, 3" aluminum 'medium' ram intake (slight extention for the TXS)

Pull your block apart. Have it honed for std size pistons or go up .5mm to 100mm. Based on my only piston experiences, I've dealt with Wiesco three times now in the past 9 months (two Subaru sets, one 100mm and another 100.5mm, and now a set of 89mm Honda pistons). I like them becasue they've given me good customer and technical support and their kits come with everything from pistons, ring packs, wrist pins and clips.

When you drop off your block (this is assuming you have a trusted machine shop), have them:
- check the crank journals and refinish if needed
- balance crank
- weigh your rods and balance if needed
- if the crank journals need to be cut down the machine shop will indicate what bearing size will be used, i.e. std or undersize
- When you order your bearings, I would get them dry film coated too. I ordered all of mine through Calico Coatings. They have ACL Race Series bearings for the Subarus.

That's about it for now as I'll probably think of a few other things later. Oh yeah, Wiseco will tell you what the minimum PW clearance there should be and what crosshatch to be cut. I went with the recommended crosshatch and the minimum PW cler and is fine.

Good stuff. Thank you.

to answer the question posed (what would i do)-

personally, i would just get a cobb tuner series stage 1 block. 2300 bucks, cant go wrong.

if people are making 500+whp with the stock block, with the only damage being to pistons, a simple stock shortblock with quality forged pistons should be adaquate for your short term power goals at the least...and possibly for your long term ones, too.

Listen to Tmarcel, he definitely knows his stuff about motors. I will add that Mahle pistons are the best you can get for the money plus they include the rings, wrist pins, and they are coated. That is what I plan to use in my motor build. As far as rods, the STi rods are pretty good. If I were to replace the rods I would probably go with Crower's unless there is a better rod out there. And definitely have the crank replaced or rebalanced and checked as tmarcel mentioned.

Being patient is key when having your motor built.

-Matt

Oh yeah, I might have jumped to conclusions. How many miles do you have, if it's low miles maybe you're just wanting to dropin pistons and bolt her back up. Only if it's low miles should you consider this IMO. Let's say your engine has suffered some det in the past and has started to deteriorate one of the bearings. You wouldn't really know unless you pulled the block apart to check. About the only thing you can do with only the pistons out is physically feel for play in the rods which wouldn't be a very good indicator. Although people have done this w/out problems.

There is about 45k on the motor. With the cross-hatch hone pattern still visible on the walls I'd think a drop-in piston will work, but I'll get it mic'd before making that decision. I've kept the detonation to what I think is a minimum. I let the UTEC pull timing quickly and when it occurs, I tune it out right away.

I'll know more of course when I get it all apart. I'm hoping there's no cyl damage below what I can see now. If there is, and it's bad, then the Cobb block might happen.

Another note. When I reach in I can rock the pistons back and forth A tiny bit. At top dead center it's almost impossible to see the motion. At bottom dead center it's more obvious, but still tight. Nothing like the video in the bobblehead thread in motorsports. Is there supposed to be any play at 45k? (I'm a poet!)

How about headwork and cams? Any thoughts there? I'd like a cam that works with stock valves etc... I think I found some on World One's site that looked like they'd be fine. I don't think I'll need stronger springs if I don't need to break 7000 rpm. But some porting and polishing, valve seat angles etc... Is that stuff valid power?

I think the only problem with the drop-in pistons is that your crosshatch might be visble but the ridges are gone. That's part of the rings seating. Even when you start over with new rings in unhoned bores, you still got the same issue.

Like you said though, have the cyl bores checked for roundness and bore consistentcy. The pistons WILL move like that so no worries. And that's on a tight bore too. At .0035 it'll be even more apparent.

Im sure cobb would work with you if you sent in your block to get built, also if you are eventually looking for a reliable 600 crank hp I would consider rods.
Anytime an engine has been ran you should re-hone and use new rings, my opinion is that it is not worth the risk.

I added some shots of the damaged cylenders and the not-so-bad cyl walls here:

http://forums.nasioc.com/forums/showthread.php?t=948330&page=2&pp=25

I think, due to financial and time-scale restraints, that I'll go with a set of drop-ins this time. Add a mild increase with the cams. Remove the tumblers, and bolt it back together.

Even if I'm wrong, and drop-ins are a bad idea, pulling the motor in this car is beyond easy. (I'll pull the engine to change the clutch next time rather than going under with the tranny jack again. That was a workout.)

It won't result in catastrophic failure instantly I'm sure. (<-- just jinxed myself didn't I :rolleyes: ) Worst-case, I'll waste 500 on pistons and 200 on gaskets while I'm in school but it'll get me going for now. In a few months I'll be back to full time employment (crossing fingers) and if need be I'll order the right stuff. A full block or more.

Cams won't be wasted (unless the motor goes with a really big bang!) so that'll be a fine upgrade.


And best case scenario, this motor carries me for another 2+ years, doubling it's current life (hard life apparently) for little investment and work. And doing so with more HP than I had last week. Not bad.

Once I break this in, I will be taking it to TopSpeed or TurboXS and getting it tuned properly this time.

Time to ebay everything. Anyone like paintball?

You realize that with cams you're also going to need to re-shim. That's going to be $$ too. You might be able to reuse some of them though. If I was you, I would just wait on the cams until the next round but that's just my way of thinking.

I don't think you're going to having problems with just dropping in some replacement pistons, but as was mentioned it's just not ideal. I've heard of devices that you can do a hone by hand (sounds kind of funny :lol: ). You should look into that. Only problem is that you don't want any crap to fall into the block where all the bearings are and also the rods are somewhat in the way.

Before you go through with all of this, atleast check by hand if the #2 and #4 rods have equivelant side play as the #1 and the #3. That's about all you can do without splitting the block. If there is you might want to think twice.

On the pistons, I again recommend the Wisecos as they also have a skirt coating and have the off set wrist pin design like your stock ones. GL

Something like these?

http://www.mytoolstore.com/kd/kdengi10.html#2833

http://www.mytoolstore.com/kd/2833.gif
I have one but it looks like such an un-precise piece of equipment. Just to knock off the glaze and to restore the swirl for breaking in the new rings? That's all it's for right? I can spin the motor on the stand and work upside down to keep filings out. Blocking off the crancase with rags or the like. Then flush everything out well.

I plan on running dyno oil. Once it's running I'll warm it up for 30 min and dump that oil. Run for 500 miles, dump that, and then go back to 3k intervals and return to synthetic after a regular oil change or two.

For cleaning the motor/ heads up before re-assembly, is there a safe chemical to use? (safe for the motor... not me. My children are already doomed to be born with hooves) Something like brake cleaner? But something that won't hurt seals around valves etc?

Brake cleaner is what I use. Leaves no residue and really cleans things up.

Disclaimer: This is not the recommended way to repair your motor - but since you're going to anyway, here's my advice ;)
I've never used a hand hone before or even seen one. I'm guessing you'll be fine with the block rotated upside down as long as the hone can get down the cyl walls with the rods still in place.

Before you do any of this take the block to a machine shop and have them check cylinder roundness and size. They probably won't charge you very much at all (like one hr labor, $80). This way you will know what's in the cards as far as the block goes.

Back to honing, what ever you do, don't use an air compressor after honing. That's going to spread crap around. Just use rags stuffed deep into the cylinder, completely masking off the inside of the block. Then use the brake/parts cleaner on the walls. Then carefully pull the rags out and spray/wipe the walls down again.

Again, check the rods for play. They should move a little side to side but not much. If any one of them moves more than the other you've got to break it down, no other option.

.....Time to ebay everything. Anyone like paintball?

Yeah. What are you selling?

Yeah. What are you selling?

3 markers, scuba tanks, stuff... I'll pm the details... or better yet, I'll start a thread in classified ads for it all after I go shoot some pics.

I know I'm adding forged pistons/ new wrist pins. And perhaps rods/bearings. After that... what is the order for required upgrades as power increases. I'm trying to get an idea of what I can afford vs. time the car is down (the longer it's down the more I can afford, so it's a patience test really.)

I plan on pulling the car out with about the same HP it had (400+ crank tuned poorly by me), but I want it to be much safer and I want it to be capable of higher numbers eventually. I'll try to get it tuned (a real tune at TopSpeed) to a good 450-500 crank HP, but I'd like it to be safe still approaching 600 crank in the future (with additional mods to support if needed) without opening the engine again.

I don't feel the need to make more high-rpm power or to raise the rev. limit. I don't feel comfortable at 7000 as is. But I'd like to have the heads gone over to improve flow.


With this strength/saftey goal, what pistons? Cobb? CP? What rods? Is the stock crank OK to 600 chp?

And for power improvement with the current setup (aiming to go from the 400+ untuned to closer to 500 tuned). Stock valves and springs? TGV delete help any? And a cam-set that's happy from 3500-5000? Where would I send the heads for a once-over?

Anyone know of a nice rebuild kit that's available? Bearings, rings, gaskets etc...? Or should I piece-meal?

Dang that's too many questions. :p Basicly: How would you rebuild this motor?

Thanks

Hello,

Everyone who builds motors will have their own opinions so here goes: We would suggest doing the pistons and bearings first. We've now rebuilt 2 dozen + 2.5L blocks and 90% have had failed because of bad pistons or bearings. If you're not going to shoot for over 600 CHP and you're not going to rev over 7000 RPM then you shouldn't need new rods. The stock STi units are very good and won't strech out or break (if you have a good tune) unless you're making over ~600CHP and reving over ~7200 RPM. How many sets of broken rods have you heard about in the EJ257? In fact, I would suggest doing the crankshaft before doing the rods.

Additionally, I would highly suggest considering a staged 2.5L shortblock because some are a very good value for what you're getting. We have designed our staged 2.5L SBs to be the best bang for the buck value; they replace the components most likely to fail and nothing excessive. They are designed for seemless reliability and are not full race motors that won't idle and have obscene piston slap. For instance, our stage 1 (rated conservatively for 535 CHP) includes:

-Wiseco custom spec overbore pistons (We love these units like tmarcel)
-Coated race bearings
-Fully balanced rotating assembly

I won't post the price here but let me say that we think that it's a true bargain. If you're looking to make 600CHP consistantly, I'd suggest going to an aftermarket crank.

Also, I would suggest skipping the cams for your application. There aren't very many proven AVCS cams on the market at the moment and cams yeild a very low HP per dollar spent ratio. Also, the cams currently on the market are better suited to higher than stock reving applications and you have said that you don't plan to rev over 7000 RPM. There are much better ways to spend this money (or less than half of it) like meth or alky injection. The stock STi heads are actually very good units. Please do not hesitate to contact us if you have any more questions.

Thanks,

Geoff
510-783-5300 / geoff@gruppe-s.com

Hey, Lets all try and sell 2ph a motor! :)

Personally I think you''ll be okay (for the amount of time you looking for) with just piston and bearing upgrades.

Save the real expensive stuff for next time.

Actually I just took down all my quick sale items. I'm just going to wait 'til I finish my degree (this May) and start getting a paycheck again. I'll either buy a Cobb block or something along those lines, or get this block machined and fixed up, and either way I do it all the right way.

I have too many miles on the car anyway. It'll do it well to sit and think about what it's done. And when it's ready to join the class again (SM) it'll also be ready to stomp the hell out of it! :devil:

Thanks for everyone's input. I've learned a bunch between my two recent threads. I hope it helps others too. I'll get a new post going when I'm building the new motor.

Hey just remember that your block is going to be better than a new one! It's already been heated and cooled . A new block is just that.

Hey just remember that your block is going to be better than a new one! It's already been heated and cooled.
What's the theory here? Just curious.

What's the theory here? Just curious.

Heat cycling. Atleast that's how it's been explained to me.

Huh...didn't realize that was any benefit for the block. Live and learn.

Yep...I've heard that from different sources. New is not always better.

haha, that only works in theory though (heat clycling = strength)...

I think you are doing the right thing there 2ph. Not that cobb or gruppe-s would be a bad option, but I am not so sure they are needed. Your lock is still probably fine and Id be willing to bet the only thing you need is a re-hone and a piston kit (I like Wiesco also as I have rebuilt a honda and a DSM with them and they work). Its likely not as serious as you think nor as difficult as you think.

The main thing to do is find a good machine shop that won't charge nutty amounts (unless they are highly reputable), won't delay you do to lazyness and is highly recommended. You could probably have that bad boy going for a lot cheaper than you think (prolly $1k with everything). headwork for a green and less than 7k? not needed at all... leave that stock head alone, cept maybe a TGV deleate but thats about as far as I would go. Sometimes you can either buy nice kits that come with the piston kits, main/rod bearings (that can be coated), t-belt and gasket sets or you can piece one together.

Good luck and keep everyone posted, Im sorry to hear your troubles.

haha, that only works in theory though (heat clycling = strength)...


I never said it was theory. What happens to metal when it's been heated and cooled? They can warp. Once the block has matured it's a better starting point.

Once the block has matured it's a better starting point.
I buy that concept, especially if your matching up the original heads - if nothing else you'll save money on the block & crank, not to mention the likelihood of a few new shim buckets.

Just measure the hell out of everything multiple times, and for godsakes don't just "drop-in" a new piston set without bore matching and a fresh hone to seat in the new rings; additionally, it would not be too wise to cut corners and reuse the old bearings - if you're doing this right the case is already split, the additional labor is meaningless, so do 'em too.

Its likely not as serious as you think nor as difficult as you think.


Just for the record, this isn't difficult. Trying to make Russian literature interesting. THAT is difficult. This is fun. I've just been unemployed for 6 months and all this tin import stuff comes at a premium.

So, took the block to Turbo Tune today and after he checked we hauled it over to his machine guy. The Cyl that suffered 2 failed lands was perfect. The one with the single failed land (that must have had several more days in the cyl.) was ovaled at that point by 1/2 of 1000th of an inch. 0.0005" of wear. That's some gentle failure right there.

So I'm back to my patience game. If I get the $$ to get the cast pistons, gaskets and timing belt (and I hope ARP studs because those 12 point stockers are annoying) and it looks like that's all I can do, then it'll be rebuilt like that, with just a re-hone. And I keep eating mac-and-cheese.

If I'm making a real income, I'll be able to wait a check or two and make it all better.

So for now I'll sulk in my garage and make all the little parts shiney.

I can save you some more money then ;) You can forgo the ARP head studs too. I've known more than one guy now to go back to the Subaru head bolts. That's what I use and many others. I haven't heard of any failures with the Subaru bolts personally.

On that #2 piston, did it wear through the crosshatch (is the crosshatch still uniform there)? If not, I would say that it's just an ovalled cylinder.

Why the move? This isn't a "built" motor. This is a 2.5 with new pistons. If anything this warrants placement in the Int. and Ext. mod and care section. I'm painting my intake blue afterall. :rolleyes:

Why the move? This isn't a "built" motor. This is a 2.5 with new pistons. If anything this warrants placement in the Int. and Ext. mod and care section. I'm painting my intake blue afterall. :rolleyes:


If you haven't purchased the new stock STi pistons yet, don't. I have a brand new "B" set you can have for a song. They are flawless.

Need new bearings? PM me; I've got a spare set.

I'd reuse the stock headbolts, as a matter of fact, I did. :) They're large for the application.

S.

What's a "B" set? Stock cast?

I'd reuse the stock headbolts, as a matter of fact, I did. :) They're large for the application.

reuse as in actually put back in the same removed bolts, or replaced with other new oem bolts?

What's a "B" set? Stock cast?

Refers to the size (A and B are nearly identical though). This minute increment helps keep the P/W clearance identical between cylinders. You can look at the top of your block to see how what yours came with. They're normally mix-matched A-B-A-A or something like that.

reuse as in actually put back in the same removed bolts, or replaced with other new oem bolts?


Depends who you ask. Ask most Subaru techs and they'll tell you that they reuse them. Ask most Internet Gurus ;) LOL! and they'll tell you not only that you can't reuse the OE head bolts but you also must have ARP head studs instead.

Me personally...thinks that you can reuse them on a moderate application (moderate is debatabe). "I" wouldn't reuse them and would just get new ones as they don't cost much. I did reuse the new set that I had put in my first build but I only had like 350 miles on them and no boost so they were still new.

Something like these?

http://www.mytoolstore.com/kd/kdengi10.html#2833

http://www.mytoolstore.com/kd/2833.gif
I have one but it looks like such an un-precise piece of equipment. Just to knock off the glaze and to restore the swirl for breaking in the new rings? That's all it's for right? I can spin the motor on the stand and work upside down to keep filings out. Blocking off the crancase with rags or the like. Then flush everything out well.


For the newbs reading this:


On the hand-hone: If I were "freshening" up an old truck engine, sure, I'd use it, and not expect alot out of the engine. On an engine I cared about, emphatically, No.

On the hand-honing without disassembly:
I wouldn't do that, period. If even a SLIGHT bit is left in your cylinders' finish, the rings will never seat....but that would be the least of your problems. There is no way you're going to prevent honing material or bore debris from getting into your bearings. :)

HTH,

S.

BTW, I use Brake-Kleen for cleaning my cylinder walls....my specific techniques are in here somewhere...probably in the 2.5L forum.

reuse as in actually put back in the same removed bolts, or replaced with other new oem bolts?

Reuse as in put 'em back in. They are torque to yield, and yet they are gigantic for the application.

I've spoke with several engine gurus sharper than I, and they all said: "Geez, over-engineering at it's finest" or, "Those would do well on a big block Chevrolet", or, "You're kidding, right?"....so I reused them...:lol: which normally, goes against the fabric of my being.

My point: Judging by the procedure in the EJ257 FSM (21 ft/lbs, 56 ft/lbs, back off 180, back off 180, 31 ft/lbs, 90*, 45*, additional 45* on the inner bolts....I'm going from memory, here, so cut me a break :lol: ), I can't see those headbolts being close to their limit....so I asked smarter folks. :)

S.

Edited for specificity :lol:

Headbolt Q:

Tell you what I'm gonna do (put this matter to an end, once and for all ;) ):

I'm going to order a new set of bolts. Measure the length.

Remove my headbolts I used in my engine. Measure the length.

Then we'll see, for sure. :lol:

S.

Headbolt Q:

Tell you what I'm gonna do (put this matter to an end, once and for all ;) ):

I'm going to order a new set of bolts. Measure the length.

Remove my headbolts I used in my engine. Measure the length.

Then we'll see, for sure. :lol:

S.

Now we got to start a new thread for that one ;)

Now we got to start a new thread for that one ;)


Count on it. :lol:

The stock bolts are on their way....now I just have to fab a fixture long enough to measure the bolts, and adapt my stretch gauge to it.

Sorry for the hijack. :D

S.