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08WRXBLUE--RIP:99-2.5RS
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Discussion Starter #1 (Edited)
I called up Wiseco Pistons yesterday and asked about buying pistons for my RS-T (99RS, sohc, ej25)- Im keeping my stock block!!!

She gave me the part # I should order from (K600M995).

I asked here about lowering my compression but she didnt seem to get what I was going toward. she just says get these pistons (even though its keeping my stock compression- which I don't want to do)

Does anyone know which one I should get? (The part #)
-I want the pistons that lower my compression.

Could I just put the sti pistons in?

http://www.wiseco.com/PDFs/Catalogs/SC07/NissanSubaruToyota.pdf
(Subaru- its part way down the page)

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Goal: around 300WHP
With AVO turbo kit
 

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2000 stage II+ S4/ 01 2.5RS-T
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I plan on doing the same thing. She didnt know what she was talking about. It says the compression ratio is 8.5 which is what you want! So go for it!
 

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how much you paying for those pistons, why not get an STI short block? It will give you STI compression that can get you down 8.5.1
 

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08WRXBLUE--RIP:99-2.5RS
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Discussion Starter #7
mozzy said:
how much you paying for those pistons, why not get an STI short block? It will give you STI compression that can get you down 8.5.1
about $420 I think. my freind is going to help me install them for free.
sti short blocks go for around $1500 I think new.

plus the sti short blocks have the whole oil line thing I dont want to get into.
 

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I need money
1998 sub 2.5rs WRB
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pistons

Just buy a set of stui piostons they fit just fine. I have a set right now waiting for my 2.5 that will be cheaper than the others. Plus you don't plan on making like 500 horses do you. Sti pistons should be fine for at least 400 horses.
 

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1998 Forester on Orange 57F
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pimptight2.5 said:
Just buy a set of stui piostons they fit just fine. I have a set right now waiting for my 2.5 that will be cheaper than the others. Plus you don't plan on making like 500 horses do you. Sti pistons should be fine for at least 400 horses.
You need to do STI rods also when doing STI pistons! I would just use the Wisecos. They are a good price and you will not have problems with them. I have over 20k on mine now with no blow by and no problems.
 

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1998 Forester on Orange 57F
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amorton said:
what are the stock RS rods good to power wise?
Same as STI rods. I would say about 500Whp. But I have never seen the rods fail do to power. The real benifit to aftermarket rods is that with heavy det they bend not brake. This saves the rest of your motor. I have seen a rod brake and take out the whole block. Although impressive, it ends up being expensive. I have also seen Wiseco pistons take heavy det without a mark later snapping a rod. Moral of the story is tuning is your friend. Don't skimp on EM!
 

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I am starting to understand. I am personaly planning on running Link-plus, hydra, or autronic we have a local dyno that really likes autronic
 

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amorton said:
I am starting to understand. I am personaly planning on running Link-plus, hydra, or autronic we have a local dyno that really likes autronic
I've used the Link-plus and Hydra. Out of those go with the Hydra. Although I have never used the autotronic and if you have a local tuner that will be tuning it I would go with what the tuner likes. If you are tuning it then go with whatever you want or are more comfortable with. I like the AEM EMS the best but that's my opinion. I also have the most time tuning it and went with it over the Hydra for my car. What I hate about the Hydra is you are not allowed to control as much as the AEM. Although for 99% of people that doesn't matter.
 

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I know spool time tends to be long on an STI short block, so would it be better to go with that, or a set of forged pistons from tech works that run something like 9.1.1 over the sti block which is 8.5.1 i think or something like that
 

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RicerSube69 said:
and if you want to run sti rods don't you have to modify them to get them to fit in the RS crank? Or is it that you have to modify RS rods to fit STi pistons?
STI and RS rods are different lengths so RS rods will not work with STI pistons ever. The big end is the same size so they bolt onto the crank fine. Infact the RS and STI cranks are identical. Now, WRX rods and STI rods are the same length but WRX rods have to be modified to fit stock STI pistons. The small end of STI rods have a tapper that fits into the STI pistons. IF you want to run STI pistons you HAVE to run STI rods. Unless you have a full machine shop at your disposal and can figure out how to machine the different lengths to work.
 

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mozzy said:
I know spool time tends to be long on an STI short block, so would it be better to go with that, or a set of forged pistons from tech works that run something like 9.1.1 over the sti block which is 8.5.1 i think or something like that
The STI short block is 8.2:1 with STI heads. With RS SOHC heads it is about 8.5-8.6:1 with STI head gaskets. With WRX heads it is 8.7:1 with STI head gaskets. I vote Wisecos because they are nice and they are made for your stock block. They also are cheaper then TWE.
 

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Brydon... Are you talking about RS phase I block or phase II. I have a phase I DOHC block and an STI short block (cracked case) and I am going to take the rods and pistons out. However, I thought that with the STI rod/pistons on an RS crank the compression is very low, like 7:1. Reddevil doug was telling me about this. Couldn't you mill down the RS ends to fit the STI piston to get some compression back?
 
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