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Discussion Starter · #1 ·
I need some advice. I just bought a JMD V7 shortblock and I’m waiting for my 18g. I want to get my rpm to 8k. My question is, what should I do with my heads? The car is going to be a daily drive car.

ThanX
 

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The flaw of the stock WRX valvetrain is the shim isnt under the bucket. It can fall out with higher or over revs.

The my04 have shimless buckets. Could easily upgrade your valvetrain.

-Mike
 

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Discussion Starter · #5 ·
So if I buy the STi valvetrain, I'll be fine? Would the US STi valvetrain work or do I need a JMD STi valvetrain?

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grantn said:
So if I buy the STi valvetrain, I'll be fine? Would the US STi valvetrain work or do I need a JMD STi valvetrain?

ThanX
Im not sure how the valvetrain is on the US STi heads yet. I haven't personally taken a us sti head apart. I know the cams will go in the WRX heads with a slight modification to the oil holes dealing w the AVCS.

I will check it out and let you know. But what are your goals and spending limit on the heads?

-Mike
 

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Discussion Starter · #7 ·
My goal is to have the car at 8k rpm with reliability. Money wise, the chipper the better.

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Why do you need to get to 8, I think the amount you spend on the valvetrain can be better spent on other horsepower mods. I can only assume other problems with higher RPM will take thier toll on other part not even in the engine ( I had a '90 Taurus SHO and the problem with the 7000 rpm yamaha built engine was the alternator, waterpump, pully's, A/C compessor and other accessories suffered cause ford didnt think about added RPM's to the basic parts when they put an engine with 2000 more rpm's than normal) I dont know what all the accessories for the Subie are rated for but in my old car they became short lived in my car and had to be upgraded over time, and you might even want underdrive pullys to slow the speed to the accessories. dont know if this info is relevant, Good luck! :D
 
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