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Old 04-21-2021, 11:18 PM   #1
Manny1274
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Join Date: Apr 2021
Default Need help with rebuild

Alright I need legitimate answers. I got an 06 wrx with the ej255 I’m pretty sure my ring lands are bad but ima confirm tomorrow but either way I have a spare ej255 block that had 50k miles and according to previous owner had rod knock but was shut off immediately and he was right cause the block looks perfect . Still has factory cross hatchings and no scoring. My question is I wanna build this block to hold about 400-500whp. I did the 6speed swap already and has a 20g turbo currently but I wanna know what’s the best pistons,rods, head gasket brands etc to run for this rebuild. I plan on getting the heads cleaned and wanna know should I also upgrade the valves and springs? If so what brand would be best. Also anything else that I would be missing?
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Old 04-22-2021, 06:37 AM   #2
snow_bound26
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The best companies are the ones your machine shop recommends. JE, CP, Mahle, etc all makes quality parts but some machine shops prefer certain companies over another. So contact whoever you're going to have do the work.

For the power level you say you eventually want, springs, valve and all wear items in the heads will be a good idea to do. OEM springs will start to float around 22-24psi. As for companies, once again listen you your machine shop. GSC, Ferrea, Supertech, etc all make quality parts. The work the machine shop puts into making sure everything has proper clearance, sealing, honing, etc is what will truly make the difference on how well and how long your engine performs.
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Old 04-22-2021, 07:26 AM   #3
Jack
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Do you plan to sleeve your block? Something to consider if that wasn't in your plans.
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Old 04-23-2021, 02:18 AM   #4
Manny1274
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Quote:
Originally Posted by snow_bound26 View Post
The best companies are the ones your machine shop recommends. JE, CP, Mahle, etc all makes quality parts but some machine shops prefer certain companies over another. So contact whoever you're going to have do the work.

For the power level you say you eventually want, springs, valve and all wear items in the heads will be a good idea to do. OEM springs will start to float around 22-24psi. As for companies, once again listen you your machine shop. GSC, Ferrea, Supertech, etc all make quality parts. The work the machine shop puts into making sure everything has proper clearance, sealing, honing, etc is what will truly make the difference on how well and how long your engine performs.
Should I sleeve the block or am I going to have to bore it? I have an ej255 with 50k miles still has perfect oem cross hatchings on cylinder walls. And as far as the machine shop with agreed to cp pistons and mahle rods and etc. but I wanna know what else is needed at this point. This is gonna be my side project for a while
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Old 04-23-2021, 07:13 AM   #5
snow_bound26
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Close decking is safer than sleeving as you won't be messing with the integrity of the OEM cyl. You're talking about a power level that's getting close to needing something to reinforce the cyl wall.

Machining the mating surfaces, boring the cyl, etc is all stuff your machinist will do if it's needed. That's not something anyone here can answer since we aren't doing measurements on the block and heads. Most likely they will need a little work and 99% certain they will bore/hone the cyl's for the new pistons. It's safer to start fresh then take a chance. Just make sure they have the proper torque plates to do the bore/hone. If not, go somewhere else.

Somethings to consider would be what turbo you will eventually use. This will dictate valve size and spring type. Smoothing out the casting marks and a pocket port will make a big difference. Everyone gets lost in building the block. Power is made in the heads, spend extra money there. Then decide where you want your power band and make a choice on cams. For the 500-600 stage 1 cams from most companies will give you a bit more top end without sacrificing street driving much. 14mm head studs to hold it all together. And make sure you have the rotating assembly dynamically balanced.

Are you using a +2mm rod? If this hasn't been discussed you should look into it. Reach out to HomemadeWRX or TiC for some insight on the advantages of +2mm rods.
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Old 04-24-2021, 01:03 AM   #6
speedyHAM
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Quote:
Originally Posted by snow_bound26 View Post
Are you using a +2mm rod? If this hasn't been discussed you should look into it. Reach out to HomemadeWRX or TiC for some insight on the advantages of +2mm rods.
If you are building an engine this is a serious consideration to make and well worth the $ spent.
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