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Discussion Starter #1
Throwing a question out for y'all. Right now my car has a nice safe custom tune done last year with the one mods being simple bolt on's. If I were to purchase a new stock long block to replace the stock long block in the car would it require a new custom tune or would my current tune still be safe?

I'm sure some of y'all would say why not pump up the power if your doing it or why are you buying a new long block if you car is running fine. Fact is I don't know just how hard this engine was beat on before I bought it and I would like to have the reassurance that the engine itself is 100% mechanically sound. To be honest right now it's putting 325 to the wheels and that is more than enough for a DD. The old block would slowly be built over time though as money allows.

Back to the original question do you think the current tune would be safe going from stock with some miles and wear to fresh stock long blocks?
 

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To be honest, i think a new tune would be best. Every engine runs differently, no engine is exactly the same. I understand your concern about want a fresh start but i dont think going for another oem block is greatest plan. You said you wanted to build a block over time, well with the money an oem long block will cost you can buy a fully built forged short block and maybe have some left over money. Use that money towards built heads. No sense is have 2 oem engines that could quiet possibly fail for the same reason. If i were you, i would save my money and put it towards a build engine. Keep driving on the current engine until it fails. Who knows, it may not fail. If thats the case then at least you wouldn't have spent the money on an engine that you aren't going to use.
 

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Discussion Starter #3
To be honest, i think a new tune would be best. Every engine runs differently, no engine is exactly the same. I understand your concern about want a fresh start but i dont think going for another oem block is greatest plan. You said you wanted to build a block over time, well with the money an oem long block will cost you can buy a fully built forged short block and maybe have some left over money. Use that money towards built heads. No sense is have 2 oem engines that could quiet possibly fail for the same reason. If i were you, i would save my money and put it towards a build engine. Keep driving on the current engine until it fails. Who knows, it may not fail. If thats the case then at least you wouldn't have spent the money on an engine that you aren't going to use.


The motor in it now still has the same tick as it did before I changed the tensioner albeit much quieter ( I think it might be because of the helicoil we used for the hole) and I can feel a small bit of rhythmic ticking through the shifter sometimes also. I know the oil looked clean(no metal sheen) when I changed and have a oil analysis kit ready once I hit 2k on the new oil just to feel safe. If it comes back good then I won't worry about a swap but if it doesn't then I'll be looking for a new engine.

The car is my DD so down time has to be minimal that's why I was just going to do a full swap so I can get it right back up and running and spend a year or two slowly building up a stout but mild engine that can be flogged from time to time but still be reliable.
 

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1) #1 for a reason! Find the noise - and fix if/as necessary before it becomes a real problem!

2) Most people consider a stock block to be fairly reliable at under 350AWHP.

3) If you are concerned about reliability then for far less than the cost of a new engine you can have a spare car. You don't have to swap engines to use it when needed. I have a 2002 Civic we bought for under $2K. I was glad to have it when I shattered my ankle and could not drive stick. I do realize that this may not be practical for city dwellers, but most city dwellers aren't talking about building their own engine - cause they'd be doing it on their kitchen table. OK, I built a VW on my kitchen table around 82 :) still . . .

4) Unless you really really want to build your own block, or you are already an Subie expert, you'll be better off buying a built short block if you ever want or need need one. Start looking here:

IAG Performance Subaru Short Block Built Engines for WRX, STI, Legacy GT, Spec B and Forester XT.
 

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Discussion Starter #5
1) #1 for a reason! Find the noise - and fix if/as necessary before it becomes a real problem!

I'm 95% confident that it is still the tensioner. When I replaced it I had to remove a old helicoil on the mounting bolt with a new one. I maybe just slightly off from the perfect stock angle so I have ordered a new bracket to put on in the coming weeks when I have time. The reason I say it's still that is it has the same sound and pattern but much much quieter. The sound was gone for the first couple days and then came back so I figure I could be a little off on the hole or when the hole was oversized slightly for the new helicoil it moved the overall position down
.020 or .030 which makes plenty of sense. I have plenty of experience in building and repairing mechanical stuff after 20 years of aircraft repair in the Marines, it was just me being aggravated and needing to get it done instead of waiting for the proper part to show up.
 

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Good on the experience :) I'd still recommend buying a short block partly because I'd rather have a place that specializes in Subaru blocks do the machining than most other shops. I know, its' not rocket science but I believe mistakes are less likely to occur . . The fact is , you don't need to do it in advance that way. You can have a block shipped pretty quickly if you ever need one - or even pick it up.

Timing belt issues can cause far bigger ones. I'm sure you are aware . . .

Going back to your original post/questions:

Throwing a question out for y'all. Right now my car has a nice safe custom tune done last year with the one mods being simple bolt on's. If I were to purchase a new stock long block to replace the stock long block in the car would it require a new custom tune or would my current tune still be safe?
I bet yes, but with that much time and money invested another $500 to update is probably safer and not a bad thing to do.

I'm sure some of y'all would say why not pump up the power if your doing it or why are you buying a new long block if you car is running fine. Fact is I don't know just how hard this engine was beat on before I bought it and I would like to have the reassurance that the engine itself is 100% mechanically sound. To be honest right now it's putting 325 to the wheels and that is more than enough for a DD. The old block would slowly be built over time though as money allows.
That's the thing no-one who has a STI not covered by warranty is doing the wisest thing the best thing replacing there stock block with another stock block. If you are going to have that much investment at least use after market pistons. You want reliability? Replace the weakest link with something stronger. Then insure the new block is properly balanced and blueprinted. After that consider upgrading the head studs and rods . . . it will run better and be able reliably handle the additional power you have and more.
 
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