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Discussion Starter · #1 ·
So, I just tore down a spare QR25DE to rebuild and replace the tired QR in my 2003 Spec V. After doing a bunch of research I come across a QR build on Motoiq. Looks cool, but then in the comments, the guy, (Mike Kojima) writing the article states that the project was never completed because the engine is NOT a good base for high power builds. Dude is pretty legit! So, now I’m second guessing my build choice. I wanted to turbo, and get a reliable 400-ish hp. I was going to overbuild it and keep boost “Turned Down”, but Kojima is saying that there is not enough bearing surface, I’m assuming on the crank, to support the power upgrades. Anyone with experience building a performance QR with some input/opinions would be GREATLY appreciated!! Before I pour money into a engine that is, potentially, just gonna grenade. Thanks in advance!
 

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Link to the article for reference, there are 2 type of motor builds he covered.

Loaded question, this isn't a popular motor so use that as your bases but on the other side of the coin there are good examples.

Your limiting issue to a degree is your ecu and I believe the only people offering reflashes for them is Nisformance right off the top of my head, maybe JWT but I'm sure there might be more out there. A step above that is converting to use the 04-06 ecus with preference to the 06 utilizing an oem wideband. This is outside piggy backs and standalones.

Fully work your stock crank or get a fully counter weighted crank, but at the same token what are you building it for.
 
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I've seen 400who turbo builds on stock motors last years. There was a gal named Jen that had one. The maintenance is the big deal. As long as you maintain the motor and turbo system religiously, you'll be fine. I'm going to be honest tho, this is with ANY motor on any car. The main reason Kojima dislikes the qr is the weak journal overlap on the crank. If we ever did billet cranks like I was trying to do we could have fixed the crank issues and just needed custom rods and pistons. But we broke community, so not enough people on board.
 

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Just did springs and lifters on the ol a4 (2013). Had a broken valve spring. How tf do you break a valve spring into two pieces!?

And don't get me started on the new set of triple square tools I have now.
 

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It took me 3 months to do a rebuild on the rear end suspension bushings cause german engineering.... weather didn't help. Need to do the clutch and fw too, gonna delay that mf.
 

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Dont listen to these fools. Stock pistons and rods, 30psi of boost, on a 20mm turbo and youll be making 800+ all day. 3K Said so. (Joking!!!)

On an 03 I would recommend going to an affordable standalone to make your tuning life easier. Even a speeduino would be easier to work with than a 02-03 ecu lol Just my opinion.
 

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Dont listen to these fools. Stock pistons and rods, 30psi of boost, on a 20mm turbo and youll be making 800+ all day. 3K Said so. (Joking!!!)

On an 03 I would recommend going to an affordable standalone to make your tuning life easier. Even a speeduino would be easier to work with than a 02-03 ecu lol Just my opinion.
That was actually the plan.
 

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Dont listen to these fools. Stock pistons and rods, 30psi of boost, on a 20mm turbo and youll be making 800+ all day. 3K Said so. (Joking!!!)

On an 03 I would recommend going to an affordable standalone to make your tuning life easier. Even a speeduino would be easier to work with than a 02-03 ecu lol Just my opinion.
What would be the best middle of the road (best bang for buck that's still around, or the cheapest and most expensive respectively; either-or) standalone ECU for an 02? I'm probably never building mine since it's becoming a swiss cheese shitbox with these midwest winters and junkyard panels being impossible to find, but it might be nice to know anyway.
 
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